Early complications and late sequelae of induced abortion: a review of the literature

ABORTION Early complications and late sequelae of induced abortion: a review of the literature KARIN G. B. EDSTROM 1 An attempt to evaluate the recent literature on somatic complications of induced abortion shows that a great amount of data of widely varying quality has been collected. Many areas of research are still not covered in a way that permits valid conclusions to be drawn. Two important points emerge from the review: first, there is a need for uniform definitions of complications and some uniformity in the analysis ofdata collected; secondly, carefully selected control groups are needed in this kind of research. The areas most urgently requiring further study differfrom country to country. From a globalpoint of view, the existence or inexistence of significant late sequelae and the influence of the patient's health status on the complication rate seem to be of the highest priority. Legislation permitting the performance of abor- tion on other than strictly medical grounds varies among countries, as does the application of existing laws. The general trend is, however, towards a liberalization of current laws and attitudes. Thus, there is an increased demand on clinical scientists to provide reliable and unbiased data on possible adverse effects of induced abortions-data that are essential for policy makers and health administra- tors. This review of the recent literature concerning somatic aspects of induced abortion brings together some of the more valid information concerning the incidence of complications and attempts to evaluate the factors influencing their frequency. It also identi- fies some of the areas in which further studies and research are required. There are obvious difficulties in comparing data from different authors; ways of collecting data and definitions of complications differ immensely. The frequent lack of adequate control groups and the sometimes obvious prejudices of the author make it difficult to draw conclusions. The papers reviewed have been selected to cover the various aspects of early complications and late sequelae of abortion as completely as possible and yet to avoid the difficul- ties mentioned above. 1 Research Physician, WHO Research and Training Centre, Karolinska Hospital, Stockholm, Sweden (present address: Medical Officer, Maternal and Child Health, World Health Organization, 1211 Geneva 27, Switzerland). TOTAL MORTALITY AND MORBIDITY RATES Mortality Reasonably accurate country statistics are avail- able only for the United Kingdom, USA (New York State), the Scandinavian countries, and some coun- tries in eastern Europe (1-5, 7). Those rates are listed in Table 1. For USA, the only material that is large enough to provide sufficiently reliable data on mor- tality is that relating to New York State since the new Abortion Act was passed in July 1970 (3). A rate for Japan, based on reported deaths attributed to legal abortion and on reported legal abortions, has been calculated by Tietze (2). The fact that the proportion of unreported abortions in Japan is unknown de- tracts from the accuracy of calculations for that country, but Tietze's calculated rates for the periods 1950-53 and 1954-58 (8.5 and 5.8 deaths per 100 000 abortions, respectively) correspond rather well to that quoted by Muramatsu (8) from a 1954 survey including 108 055 cases with a mortality of 7.4 per 100 000 abortions. The figures from Korea estimated by Hong (7) are included for comparison, since induced abortion (even outside hospital) is con- sidered to be performed almost exclusively by spe- cialists in obstetrics and gynaecology. The mortality for different methods has been analysed for 402 000 abortions performed in New York in 1970-72 (3). Uterine aspiration had the lowest rate, 1.1 deaths per 100 000 abortions, dilata- tion and curettage came next with 2.4, and saline 3332 - 123 - BULL. WORLD HEALTH ORGAN., Vol. 52, 1975 KARIN G. B. EDSTROM Table 1. Mortality due to induced abortion in several countries Mortality per ReferenceCountry Period 100000 Source of information No. abortions Hungary 1964-67 1.2 David, 1970 (1) Czechoslovakia 1963-67 2.5 David, 1970 (1) Yugoslavia (Slovenia) 1961-67 5.7 David, 1970 (1) Japan 1959-65 4.1 Tietze, 1971 (2) USA (NY) 1970-72 5 Tietze et al., 1973 (3) United Kingdom 1970 12 Office of Population (4) (England and Wales) Censuses and Surveys, 1973 Sweden 1965-69 13 National Health Board, 1972 (5) Korea (Seoul) 1967 60-125 Hong, 1970 (7) (estimated) instillation in 53 000 cases had a rate of 18.8. Hysterotomy shows a very high death rate-5 for 2 400 abortions, or 208 per 100 000-but this might be due partly to factors such as health status and age (see below). In the United Kingdom in 1969, the reported mortality for 31 000 uterine aspirations or dilatations and curettages before the 13th week was 6 per 100 000. For 3 700 first-trimester hystero- tomies it was 80 per 100 000, and for second- trimester hysterotomies 90 deaths per 100 000 abor- tions (9). Morbidity The morbidity rates associated with induced abor- tions (Table 2) also vary substantially among the different countries (5, 6, 10-19) but not to the same Table 2. Morbidity rates associated with induced abortion in various countries and with different methods of collecting data Country Period Method of collecting data Moorbidityper Source of information abNonI 00 abortions ~~~No. USA (NY City residents) July 1970-March 1971 reports to Department of Health 1.0 Pakter E Nelson, 1971 (10) USA (Hawaii) 4 months, 1970 reports on 1 169 cases 4.1 Smith et al., 1971 (11) Czechoslovakia 1963 reports to Department of Health 2.3 Mehlan, 1969 (12) Hungary (Budapest) 1960-69 reports to Ministry of Health 2.6 Czeizel & Bognar, 1971 (13) Denmark 1961-66 reports to Ministry of Health 4.7 Olsen et al., 1971 (6) United Kingdom 1969 reports to Ministry of Health 3.4 Huntingford, 1971 (14)(England and Wales) USA (JPSA study) July 1970-June 1971 survey with follow-up of 1.0-1.6 a Tietze E Lewit, 1972 (15) 73 000 cases 9.6-13.1 b Hungary (Budapest) 1966 survey of 55 000 cases 7.3 Bognar, 1969 (16) Poland (Warsaw) 1958-68 survey of 3482 cases 8.4 Sternadel et al., 1968 (17) Sweden 1964 survey of 1 427 cases 18.5 1965 Committee on (5) Abortion, 1971 United Kingdom 1967-70 survey of 1 317 National 16.8 Sood, 1971 (18) Health Service cases Czechoslovakia 1968 'informal estimation 15.0 Kuck, 1969 (19) by gynaecologists" a Major complications. b Total complications. 124 ABORTION 125 Table 3. Early complications occurring in connexion with uterine aspiration and with dilatation and curettage. Number of different complications per 100 abortions Total Incomplete Proain CervicalStudy complication Bleeding Infection evacuation Perforation trauma rate Uterine aspiration range of complication rates a in literature reviewed 0.8-7.3 - 0.8-5.0 0.5-10.4 0.03-1.7 0.03-4.9 total complications 4.7 JPSA (15) 1.2 1.5 - 0.3 0.9 major complications 0.5 (incl. fever only) Vladov et al. (28) 5.2 66 ml b 1.6 - - - Jurukovski & Sukarov (23) 3.9 - 1.13 1.82 0.03 0.03 Lunow et al. (26) - 1.0 C - - 0.3 0.9 Beric & Kupresanin (21) - - - 1.3 0.4 - Dilatation and curettage range of complication rates a in literature reviewed 5.4-15.3 - 0.87-55.6 0.7-3.8 0.12-2.1 0.16-3.9 (5-10) d P total complications 6.7JPSA (1 5) I major complications 0.6 Vladov et al. (28) 9.0 85 ml b 3.5 - - - Jurukovski & Sukarov (23) 4.8 - 1.65 1.60 0.03 0.16 Lunow et al. (26) - 2.1 c - - 2.1 3.9 Beric & Kupresanin (21) - - - 3.8 0.12 - a Includes authors under references Nos 6, 15, 18 and 20-29. b Mean blood loss (300 cases with uterine aspiration, 280 with dilatation and curettage). c Percentage of patients requiring transfusion. d Range of most studies reviewed. extent as mortality rates, and the manner in which data are collected plays a much more important role. Czeizel & Bognar (13) compare the complication rate in Budapest based on reports to the Office of Statistics during the period 1960-69 with that found in a survey of 55 000 cases in that city during 1966. They find a reported rate of 2.6%, whereas the survey showed that 4.2% were treated in hospital for complications resulting from abortion. Bognar (16) adds complications registered in outpatients, giving a total morbidity of 7.3% for the 1966 survey. An even more pronounced difference is seen during identical periods in USA between morbidity in New York City based on reports and morbidity in the JPSA a study including follow-up. The different ways of defining morbidity and complications account for some of the differences shown in Table 2, but this factor is probably more important when one tries to interpret and compare a Joint Program for the Study on Abortion, see Tietze & Lewit (15). data such as those reviewed in the following sections. Gestational stage at abortion, parity, and health status are important factors influencing morbidity, and they will be dealt with separately later. EARLY COMPLICATIONS IN RELATION TO THE METHOD USED First-trimester abortions These are performed, almost without exception, either by " classical curettage " (dilatation and curet- tage) or by suction curettage, otherwise known as uterine aspiration. Both methods have a low total complication rate (Table 3) compared with second- trimester abortions, but the range of complications reported by different authors varies markedly, as do their definitions of complications (6, 15, 18, 20-29). Prospective studies with direct comparison of the methods (15, 28) show somewhat superior results for uterine aspiration but perhaps not such a pro- KARIN G. B. EDSTROM Table 4. Complication rates (No. per 100 abortions) and deaths associated with intrauterine saline infusion Study No. of patients Total rate of No. of deaths Bleeding Infectionscomplications JPSA, Tietze & Lewit (33), 14 690 23.4 3 a 17.2 4.8 USA (major 1.7) Bengtsson (34), Sweden: intra-amniotic 2 797 - 2 b 5.0 e 1.6 f extra-amniotic 3364 - 1 c 7.8 e 2.3f Olsen et al. (6), Denmark 6940 4.5 3 d - Kerenyi et al. (35), USA 5000 - 0 2.3 a One patient (schizophrenic) committed suicide one month after the abortion; one developed hypernatraemia, convulsions, and renal failure. The third died from severe haemorrhage after partial separation of the placenta. b One probably related to intravenous injection; one cardiac arrest in a patient with congenital heart disease. c Septicaemia. d One patient died 13 days after abortion as a result of laparotomy for sterilization. e Percentage of patients requiring transfusion. f Symptoms of pelvic infection. nounced difference as has sometimes been claimed (24). Bleeding is usually not an extensive problem with first-trimester abortions (Table 3). Sometimes, how- ever, it has been reported in a very high proportion of cases, usually combined with a high proportion of operations beyond the 12th week. Thus, Stallworthy et al. (27) in almost 800 cases terminated by uterine aspiration, report a blood loss of 500 ml or more in 17% and haemorrhage requiring transfusion in 8 %. Infection shows the same distribution as the total complication rate. The very wide range reflects the great differences in the definition of infection, rang- ing from a temperature of 37.5°C to peritonitis. Incomplete evacuation of the uterus is the only complication reported slightly more often with uter- ine aspiration (24, 28, 30). Beric & Kupresanin (21) find the reverse to be true, but their two series are for different time periods and received different types of anaesthesia. Perforation of the uterus is infrequent, especially when uterine aspiration is used for induced abortion in countries with a high abortion load (21, 23, 26). In England several clinics using mainly this method (up to at least 14 weeks) report a perforation rate of 0.5-2.7% (18, 25, 27). Stallworthy et al. (27), during abdominal tubal ligation after uterine aspiration, found previously undiagnosed perforations in 3 pa- tients. Treatment is usually laparotomy and repair or hysterectomy, but conservative treatment is often successfully applied. In the JPSA study (15), of the 187 perforations reported 88 were handled success- fully with conservative treatment. Cervical trauma parallels perforation, and is usu- ally reported 3-5 times as frequently (15, 23, 26). Trauma to the uterine myometrium, defined as smooth muscular tissue found during histological analysis of scrapings from the uterine cavity, is frequently reported with dilatation and curettage, and Andreev (31) reports " deep injury to the muscu- lar wall" (in his opinion carrying a serious risk of intrauterine adhesions) to be 38 times as frequent during dilatation and curettage as during uterine aspiration. Second-trimester abortions Intrauterine instillation ofhypertonic solutions. The most extensive experience with this method so far has been in Scandinavia and lately in USA. In Japan it was formerly used extensively but not always with safety precautions, and the method has now been abandoned there because of high complication rates (32). The complication rates found in the JPSA study (33), a retrospective survey by Bengtsson (34), a consecutive series of 5 000 saline abortions by Kerenyi et al. (35), and an analysis of reports to the Danish Medical Health Board (6) are shown in Table 4. Bleeding is a much more frequent complication here than with first-trimester abortions. In Bengts- 126 ABORTION 127 son's study, which was based on an inquiry in all Swedish centres performing induced abortions, haemorrhage was said to have occurred when the patient received a blood transfusion. The fairly high rate of this complication probably reflects a generous attitude in Sweden towards replacing blood loss, but on the other hand there is evidence of a frequent decrease in coagulation factors after intra-amniotic saline instillations in otherwise uneventful cases (36-39). Infection is less common than haemorrhage, but is more frequently seen than with first-trimester meth- ods (5, 33, 34). The incidence of infection following instillation of hypertonic glucose is usually higher than that following saline (5, 40). Retention of placental tissue is reported at ex- tremely varying rates, owing to different attitudes of operating clinics. In many cases curettage is per- formed routinely after abortion. The failure rate is dependent to a great extent on the patience of doctors and patients but also on the solution used, the technique applied, etc. (discussed below). Schulman et al. (96), in inducing abortion by intrauterine saline injection in 323 outpatients, expe- rienced only one failure (with a living fetus 3 weeks later), but 13 patients took more than a week to abort. Bengtsson (34) reports a rate of 96.5% abort- ing after the first intra-amniotic instillation and 85.1 % after the first extra-amniotic instillation. The efficiency rate for the first intra-amniotic instillation in the JPSA study (15) was 95.5 %. Kerenyi et al. (35) give a corresponding figure of 98.6% success for the first instillation and 0.4% total failure for the last 1 000 patients in their series. Glucose is less efficient and failure rates of 15-22% are reported (27). Symptoms of intravasal injection of hypertonic saline, sometimes combined with amnion embolism, are evident in a large proportion of case reports (6, 32, 34, 41, 42). The frequency of accidental transfu- sion is not known, but Gustavii (43), in 10 of 69 extra-amniotic instillations, by adding roentgen con- trast medium could prove an immediate shift of fluid into the veins. Intravasal haemolysis (36), hyper- natraemia (43, 44), and changes in blood volume (42, 44) have been seen, but marked changes seem to occur only in connexion with symptoms of intra- venous injection. Hysterotomy and hysterectomy in the JPSA study (15), showed the highest complication rates of all methods: 38.0% and 51.2%, respectively; yet Olsen et al. (6) reported a complication rate of only 2.5% for hysterotomy and sterilization in 6 544 cases. However, all authors (6, 15, 18, 45) agree that the complications are definitely more serious. The re- ported incidence rates of " major " complications in connexion with hysterotomy and hysterectomy in local a JPSA patients are 9.4% and 17.1 %, respec- tively, compared with a total incidence of major complications of 1.6%. Vaginal hysterotomy, ac- cording to Lindahl (46), had a low immediate com- plication rate, but he found endometriosis in the scar in 19.8% of 840 follow-up cases. Other methods, such as soap, Utus paste, urea instillations, bougies, laminaria tents, and Rivanol, are used in some countries to a considerable extent but are usually very poorly reported, and the compli- cation rates are difficult to estimate. For the period 1961-66, Olsen et al. (6) report 1 275 cases aborted with cremor saponis and a complication rate of 9.1 %-the highest produced by any method used in their series-and most European and American authors agree that the complications arising with the above-mentioned methods are more alarming (6, 45, 47-51). Rivanol 0.1% given by extra-amniotic instil- lation is possibly more promising. The abortive effect is about the same as that of saline, it has a slight oxytocic effect in vitro (52), and the incidence of infection seems to be low (49, 52). It is claimed to be atoxic (used as a bladder disinfectant) and actu- ally many of the fetuses are aborted alive. However, Pytel et al. (53) cite 4 cases of renal failure possibly related to the instillation of this solution. The numerous research projects on prostaglandins for the induction of abortion have been concerned mainly with the mechanisms of action and the effectiveness of various routes of administration. However, the substances also have pronounced sys- temic effects when administered by the intravenous, route. Anderson & Speroff (54) in a tolerance study infused PGF2a in doses of 25-200 jig/min in 10 patients. The incidence of nausea, vomiting, and diarrhoea was 90 %, 5 patients developed some degree of diastolic hypertension during infusion, and another developed a severe vasovagal shock and bradycardia lasting 45 min after the infusion was stopped. The techniques at present under investigation do not involve the intravenous route of administration. The intra-amniotic or extra-amniotic instillation of small amounts of prostaglandins (55-57) have in- creased the success rate and decreased the occur- rence of side effects such as those mentioned above. a Excluding patients residing outside the service area. KARIN G. B. EDSTROM The Task Force on the use of Prostaglandins for Regulation of Fertility is now working on finding the best techniques and compounds for induction of abortion. LATE SOMATIC SEQUELAE TO INDUCED ABORTION A large number of late sequelae have been attri- buted to induced abortion, without any proved cause-relationship. Some sequelae have been studied more thoroughly than others-mostly those related either to the woman's ability to conceive after abortion or to the outcome of her subsequent preg- nancies. Wynn & Wynn (58) in 1972 published a review on the side effects of induced abortion, containing a large part of all statements made against it and studies with adverse findings. This article has been much discussed in the United Kingdom and, among others, Trussell (59) and Potts & Shadbolt (60) have admirably pointed out the pitfalls in their reasoning. No gynaecologist who has performed an induced abortion ever tries to deny that it can give rise to early or late complications. But every gynaecologist also knows-which Wynn & Wynn seem to for- get-that all other terminations of pregnancy, such as delivery or spontaneous abortion, also can produce the same type of complication. Furthermore, the fact that the woman applying for abortion is already pregnant must be accepted and taken into account when complications are discussed. All studies without adequate control groups (which here means comparable as regards both the previous number of pregnancies and the health and nutritional status) will show only that there are complications and not whether this way of terminating the preg- nancy is more dangerous than letting it terminate by itself (or by clandestine abortion). This is unfor- tunately true of most retrospective studies published on this problem. Studies on psychiatric or emotional sequelae of induced abortion are not discussed in this paper. Such sequelae are too dependent upon national legislation and social attitudes to permit meaningful comparison of studies from different countries. The somatic sequelae most seriously investigated are discussed below. Reduced fecundity. Retrospective studies have sometimes blamed induced abortion as the cause of infertility (61, 62). However, Hayashi & Momose (63) compared a group of women complaining of secondary infertility with a group of multigravidae delivered at full term and found no difference be- tween the two groups in the proportion of women having experienced an abortion. The only exception was seen among those having experienced only one previous pregnancy, where the percentage of induced abortion among infertile women was 41.1 and that in the control group 32.6-a high incidence of aborted primigravidae also in the control group. In prospective studies by Lindahl (46), mainly involving vaginal hysterotomy, and by Jiratko et al. (64), probably covering primarily uterine aspiration, no definite evidence of reduced fecundity could be found. Premature births and spontaneous abortions in retrospective studies from Japan (65) occurred more frequently in women with previous induced abor- tions, among patients with premature deliveries, spontaneous abortions, or habitual abortions, than in control groups with full-term deliveries, but the latter were not matched according to age, social group, or parity. The same is true for Dol6zal et al. (66), who found a significantly higher proportion of previous induced abortions among 189 mothers with premature deliveries than in a control group of 197 women delivered of full-term babies. Other clinical studies also have shown an in- creased risk of premature delivery or second-tri- mester abortion after an induced abortion (67-69), but the control groups are usually never matched for both parity and health status, and it remains to be shown whether this increase is caused by the abor- tion procedure, by factors hidden in the decision to interrupt the pregnancy, or by both. Data from Hungary, where the incidence of low birth-weight is the highest in Europe, as is the incidence of abor- tion, seem to indicate that other factors also play an important role. In a survey in 1970 (70) they found that the rate of live-born babies weighing less than 2.5 kg increased with the number of previous induced abortions, there being a 100% increase with 0-2 previous abortions and 200% at 4 abortions. However, the proportion of women with premature delivery but no previous abortion was also very high: 10.1 %, and the total percentage was 11.8. There was a successive increase from the 1960 percentages, but this was true also for women with no previous abortions, 8% of whom that year had babies weighing less than 2.5 kg. During the same time the proportion of still births decreased at ap- proximately the same rate as that of babies with low birth-weight increased. The Hungarian perinatal mortality study (71) showed the proportion with low 128 ABORTION birth-weight to be higher in manual workers and in smokers than in nonmanual workers and non- smokers, and the effect of these factors was appar- ently of at least the same magnitude. An increased frequency of extrauterine pregnan- cies has been mentioned by several authors, mainly from eastern Europe (30, 61, 72, 73). Cernoch (73) analyses the change in the numbers of ectopic preg- nancies, induced abortions, and deliveries in Czecho- slovakia in 1955-68, and he claims an increase in the former, parallel with the increase in induced abor- tions. During the years 1964-68, however, there is a decrease in the number of ectopic pregnancies in spite of a stable total number of pregnancies and a slight increase in induced abortions. Beric & Kupresanin (21) find, in Novi Sad from 1960 to 1970, an increase in the birth rate and in induced abortions but a relative decrease in the number of extrauterine pregnancies. Kur6iev et al. (72) report that 48.2% of the patients treated for extrauterine pregnancies in Skopje in 1967-68 had a previous induced abortion, but do not mention the abortion ratio in the population. Sawasaki & Tanaka (74), in 222 cases of extrauterine pregnancy among Japanese women, find that the preceding pregnancy was ter- minated by induced abortion in 43.8%, which does not differ significantly from the 50.2% found in a control group. The complication rate in subsequent pregnancies and deliveries, i.e., full-term deliveries, is also claimed to be affected by previous abortion. Thus, Lembryck (69), in his group of 143 primiparae (second gravidae) with a previous interrupted preg- nancy, finds a higher frequency of bleeding during pregnancy and delivery and a somewhat longer first stage of labour, but a lower rate of toxaemia and no difference in the numbers of spontaneous deliveries. His control group consisted of 143 primiparae, primigravidae. Atanasov et al. (75) found 67.5% complicated pregnancies or deliveries in 265 women with previous abortions, compared with 13.4% in 418 with no previous abortion, the main complica- tions being bleeding and toxaemia. He does not give data on parity in the two groups. Czeizel & Bognar (13), in a preliminary analysis of legal abortions in Hungary, found a rising incidence of deliveries com- plicated by placenta praevia and abruptio placentae that to some extent paralleled the rise in abortions. On the other hand, Heczko et al. (76) studied 173 parturient women who had had their first pregnancy terminated by abortion, and they found the same rate of late pregnancy and delivery complications and the same perinatal mortality as among 18 226 other parturients during the same period. Furusawa & Koya (77) compared a large group of women terminating their first pregnancy by induced abor- tion and their second pregnancy by delivery with a control group of primiparae, primigravidae, matched for age and civil status. They found so significant difference in birth-weight, rate of instru- mental deliveries, amount of bleeding, or length of the third stage of labour, although possibly a moder- ate increase in the length of the first and second stages in the group with previous abortions. Doleial et al. (66) did not find previous abortion more often in mothers giving birth to small-for-date children (<2.5 kg at term) than in mothers having children weighing more than 2.5 kg. Evidence of the risk of Rh immunization through transplacental haemorrhage owing to induced abor- tion is rather convincing (78-85), although the inci- dence of significant transplacental haemorrhage in the first trimester is apparently lower than that in the second (79, 84). In 145 Rh-negative patients who underwent induced abortions, Queenan (84) found immunization occurring in 8 patients (5.5 %), and only one of these patients showed circulating fetal erythrocytes immediately after abortion. Four of the immunized patients were 12 weeks pregnant or less. There is little evidence of menstrual disorders after induced abortions. Mandausova & Exnerova (86), in a follow-up of 43 girls below 16 years of age, found menstrual disturbances (unspecified) in 26 patients and amenorrhoea in one. The lack of a control group, however, is especially disturbing in a study of menstrual patterns in this age group. Matsumoto & Ozawa (87), in a retrospective study, compared a group of patients with abnormal menstrual patterns and another with a normal pattern, and they found no significant difference between the two groups in the incidence of induced abortion. In a prospective study of the two cycles directly following induced abortion, the same authors showed an abnormal basal body temperature- curve in 38% of first cycles compared with 8.8% of cycles in a nonpregnant control group, but the pattern was quickly restored to normal. Thus a critical look at the literature on late sequelae of induced abortion shows that, in spite of consider- able experience with legally induced abortions in some countries, we still have very little knowledge of the types of sequela that may or may not occur. This particular literature is very interesting, on the whole, when looked upon as a study of biases and their 129 KARIN G. B. EDSTROM effect upon research. The fact still remains that there is a need for unbiased, prospective or retrospective, but in either case carefully controlled, studies in this field in a large number of women. TECHNICAL ASPECTS OF PREVENTION OF COMPLICATIONS A considerable amount of work has been under- taken on complications in relation to the type of abortion care offered, but it is difficult to draw conclusions, owing, among other things, to the scarcity of controlled studies, the sometimes ill- defined study population, and the biases of the investigators. The following observations do not attempt to suggest any solutions but only to review data already available on these aspects. The technical training of doctors is generally on a higher level in countries such as Hungary than in, for example, Scandinavia. In all likelihood, this is due partly to the higher abortion load in the former; however, no direct studies of the role of training have been encountered. In New York City and New York State the complication rates for operations performed by obstetrician-gynaecologists and by general practitioners have been compared (88), and the data are shown in Table 5. The numbers given are complication rates in percentages for first-trimester abortions. The numbers of saline abortions per- formed by the four groups of doctors were too small to allow any conclusions to be drawn. The health status of the patient is obviously of importance for morbidity and mortality from induced abortion. Tietze & Lewit (15) report in 1 223 patients with pre-existing complications (excluding cases with simultaneous sterilization) a total compli- cation rate (including follow-up) of 23.3 %, with major complications in 3.5%, compared with the rates of 1 1.1 % and 1.0% in healthy women. Age influences complication rates at both ends of the fertile period, but the data presented by different authors (86, 89-91) do not consider age and parity simultaneously. Huntingford (90) finds an age-speci- fic mortality rate, for the 17 deaths in the United Kingdom in 1969, of 9.2 per 100 000 in the age group 35-44 years, compared with 1.8 per 100 000 for the age group 20-34 years (the percentage of patients also sterilized was equal in both groups). Morbidity does not seem to be so obviously influ- enced in the higher age groups. Two recent surveys from Scandinavia, with 570 (89) and 450 (91) pa- tients, respectively, both show a higher morbidity for Table 5. Complication rates related to training level of doctors. Data from Ingraham & Longood (88) Area Obstetrician- General practitioners NY State 3.0 % (18/601) 10.2 % (10/98) NY City 3.1 % (26/831) 3.5 % (5/143) abortions before the 13th week in the younger age groups but no rise, and, according to the latter (91), possibly a decrease of morbidity in the age group above 38 years. In the JPSA study, Tietze & Lewit (unpublished observations, 1971) found an increase in complications after first-trimester abortions in the two age groups at the extreme ends-women 14 years or less and 40 years or more. For the youngest age group they demonstrated a 44% increase com- pared with the lowest rate, found in the age group 18-19 years. The increase in the oldest age group was almost as high: 40%. For second-trimester operations (mainly with saline) there was no rise at the extreme ends of the age scale, all age groups after 25 years having a complication rate approximately 40% higher than the average rate for the first trimester. An influence of parity on morbidity is often postulated, and especially the deleterious effect of interruption of the first pregnancy on subsequent fertility and the danger of habitual abortions. Stall- worthy et al. (27) find in their material no significant difference between the frequency of cervical trauma in primigravidae and that in multigravidae, and Drac & Nekvasilova (68) find no difference between women with termination of their first pregnancy and women with termination of later pregnancies in the incidence of premature birth and spontaneous abor- tion, but it is not clear how this apparently retro- spective material was selected. Atterfeldt et al. (89) studied the early complication rate (including one month's follow-up) in 171 primi- gravidae and 391 multigravidae, and they found in first-trimester abortions (uterine aspiration only) a significantly higher incidence among primigravidae, predominantly of infection and of " suspected infec- tion ". In the second trimester (only saline abortions) they found no significant difference in the total incidence but a greater frequency of profuse bleeding among multigravidae. Tietze & Lewit (15), on the other hand, found a somewhat lower incidence for 130 ABORTION 131 Table 6. Complication rates related to gestational stage. Data from Huntingford (90) Gestation Uterine Pilatation & Abdominal Hysterotomy(weeks) aspiration curettage hysterotomy <13 4.9 5.6 10.0 16.9 13-16 9.0 6.2 12.1 26.0 >16 22.9 1.5 8.6 10.0 primigravidae in both trimesters, with an especially pronounced decrease for the second trimester. Gestational stage is considered in almost all papers published, and the complication rate invariably in- creases with increasing age in weeks. A more distinct rise can be seen after the first trimester, as in the JPSA report (15). This is not solely dependent on a shift from vaginal to other procedures, as can be seen in Table 6, where all methods represented show a higher complication rate at 13-16 weeks than before 13 weeks. In the first-trimester abortions, Tietze & Lewit (15) reported a slightly higher incidence of complica- tions before 7 weeks. In " abortion only" a local patients with follow-up, they found 7.0% compared with 5.1 % from the 7th to the 8th week, which is the optimum period. They also found a maximum com- plication rate in the period 17-20 gestational weeks. Moberg et al. (92) analysed the early complications in 1 123 patients aborted by uterine aspiration, and found an increase in heavy bleeding with gestational stage, the rate being unacceptably high after the 11th week. For infection there was no corresponding increase. Induced abortion in outpatient clinics has only recently been performed more extensively. For instance, Beric & Kupresanin (21) reported from the clinic in Novi Sad that 97.6% of the abortions prior to the end of the 12th week of pregnancy are performed in outpatients by means of uterine aspira- tion and paracervical block. Nathanson (93) re- ported an experience with 26 000 outpatient abor- tions in New York in 1970-71 with a very low complication rate. Margolis et al. (94) compared the results of uterine aspiration in 55 outpatients and in 50 inpatients and found no difference in the compli- cation rate. The complications registered all devel- oped between the 3rd and the 30th day after abor- a Excluding patients with pre-existing complications and/or simultaneous sterilization. tion. In the JPSA study (15) the incidence of compli- cations associated with uterine aspiration was lower for outpatients, the difference being more pro- nounced the farther advanced was the stage of pregnancy. This might have been due partly to selection of the patients according to their health status, and partly to discrepancies between estima- tions of the gestational stage by uterine size and by the last menstrual period. Two series of outpatient saline abortions are reported, both without control series and with selected cases. Kerenyi (95) injected saline into 50 patients who were later hospitalized during labour and usually stayed for 2-7 h after abortion. If labour had not started after 36 h, an oxytocin infusion was started. Schulman et al. (96) report on 323 patients of whom 211 aborted at home, the others preferring to return to the clinic during labour. None of the authors find more complications with saline abortions in outpatients than in in- patients; Schulman, however, could not reach 53 of his patients for follow-up. First-trimester operations In uterine aspiration and in dilatation and curet- tage, cervical dilation is performed quickly and with force applied to a rather rigid cervical wall. The risk of rupture or tear is definitely greater the larger is the size of the uterus, thus, Lunow et al. (26) found before 9 weeks 0.9%, and at 9-12 weeks 2.5%, of cervical trauma. The " vibro-dilatator ", claimed to be less traumatic, is criticized because of the in- creased hazard of perforation (30). Newton (97) used it for dilatation before uterine aspiration in 165 women and reported 12 cases of serious lacerations or perforations, compared with 1 case of laceration in 500 women when he used laminaria tents. Hulka and his group in Chapel Hill (98) have recently worked out a method for objectively measuring the energy needed for dilatation and are carrying out controlled studies of the effect of various anaesthe- tics, oxytocins, and techniques, but data have not yet been published. The 6-mm Karman cannula sub- stantially reduces the need for dilatation in preg- nancies up to 8 or 9 weeks (99). No comparative studies regarding this method have been published so far. The complication rate seems to be low, with an overall rate of 4.7% in 1 554 cases from 9 studies, but there exists possibly a greater risk for retained tissue. The benefits of local anaesthesia, given as para- or intracervical block in first-trimester abortions, have KARIN G. B. EDSTROM been stressed by many authors (21, 24, 100-102), but few comparative studies have been performed. Margolis et al. (94) compared the results of light general anaesthesia and of paracervical block in patients aborted by uterine aspiration, and they found a significantly smaller blood loss in the latter group. The whole procedure in the operating theatre took approximately 50 min for the latter group, compared with 30 min for the first. Tietze & Lewit (15) compared JPSA data for general and local anaesthesia in hospital outpatients and found a total complication rate of 7.2% for abortion under local anaesthesia and only 4.8% for general anaesthesia. This higher complication rate for local anaesthesia is especially true for repeated curettage owing to reten- tion of placental tissue, which is 2-3 times more common after local anaesthesia. Major complica- tions, on the other hand, are more frequently en- countered among nonprivate patients receiving gen- eral anaesthesia. Halothane and similar inhalation anaesthetics relax the myometrium and decrease its sensitivity to oxytocin, and they have been shown to produce a substantial increase in blood loss (92, 103, 104). In a follow-up of 76 women with first-trimester abortion in Sweden (5), 21 of 37 women receiving local anaesthesia related that they would have pre- ferred a general anaesthetic, whereas only 2 of 39 receiving general anaesthesia would have preferred a local anaesthetic. Oxytocic drugs applied before or during dilatation significantly reduce the blood loss, according to several authors (21, 25, 105, 106). Johansson (107) compared this parameter in two small series of dilatation and curettage with and without intra- venous infusion of oxytocin at about 1 IU/min throughout the operation. In a group of 29 patients who did not receive oxytocin 11 bled approximately 500 ml during the operation and 9 showed significant late bleeding, whereas, in another group of 84 patients who received oxytocin, 5 bled during the operation and 5 afterwards. The type of equipment used for the abortion procedure seems to be wholly dependent on per- sonal taste; no comparative studies on complication rates exist. The negative pressure used for uterine aspiration is important. Most authors seem to use about 0.7 atm (0.071 MPa), increasing with gesta- tional stage but not exceeding 0.9, as the incidence of perforation is claimed to be higher with stronger suction (23, 25). Cernoch (108), on using 0.8-1.0 atm (0.081 MPa to 0.1 Mpa), in 20% of his cases found muscular tissue among the removed tissues. Chalupa (109), using about 0.5 atm (0.051 MPa), did not succeed in removing the fetus in 5 %. Second-trimester operations The solution most commonly used for intrauterine instillation procedures is 20% saline. This concen- tration seems from numerous reports to be optimum for safety and efficiency (32, 34, 40, 110). Glucose in 20-50% concentrations has a lower efficiency and a higher incidence of infection (27, 40, 111); 25% Mannitol and urea are both connected with a much lower incidence of effectiveness (47, 112-114). Riva- nol and other methods were reviewed above. Abdominal puncture is the prevailing technique for intra-amniotic injection in most clinics. The transvaginal route was described by Ruttner (115), who had good results in a small series, but this technique has never become popular. Instillation through a catheter is preferred by some authors (34, 116) as it seems to minimize the risk of intravascular injection. The amount of amniotic fluid removed seems unimportant for effectiveness; Reiss (116) had good results in 84 cases by removing no fluid at all before injecting the saline. There is no evidence that the amount of saline injected plays a major role in the failure rate, but amounts of less than 100 ml tend to have a reduced effect (33, 34, 117). Amounts of sodium chloride exceeding 40 g should be avoided, even in patients with normal renal function, as they substantially increase the risk of deleterious hyper- natraemia and renal dysfunction (32, 34, 118, 119). The extra-amniotic technique is rather extensively used in Scandinavia in spite of its somewhat lower efficiency (34), probably because the procedure is considerably easier. Bleeding and infection are slightly more common after extra-amniotic than after intra-amniotic injection. Oxytocic infusions are extensively used to shorten the time lapse between injection and abortion, and most authors claim that they have this effect (110, 112, 113, 118, 120), but few valid controlled studies exist. Cheng & Ratnam (120) administered oxytocin 24 h after injection into 24 patients in increasing doses up to 80 IU/500 ml and 50% aborted within 30 h, but this does not seem to differ significantly from Kerenyi's results with 200 patients not receiv- ing oxytocin and a mean abortion time of 36.5 h (95). There is evidence that the effect might be both dose- and time-dependent. Mackenzie et al. (121) gave oxytocin in doses of 100-200 IU in 500 ml of saline infused at a speed of 12 drops per 132 ABORTION minute until the patient aborted, starting within 12 h of injection in 283 patients and after 12 h in 105 patients. The mean time lapses were 22 h and 32 h, respectively, and the difference is statistically signifi- cant. Several authors have shown that, during the first hours after saline injection, a temporary de- crease in urinary output and/or changes in blood volume often occur (42, 44). Oxytocin has a fairly weak antidiuretic effect, but in doses of 600-1 000 IU in a few hours and combined with high water loads (122) the risk of water intoxication is evident even in patients with healthy kidneys. The optimum range of oxytocin in blood for the stimula- tion of mid-trimester pregnancy myometrium, ac- cording to Caldeyro-Barcia and Sareno (123), is 0.12-0.25 IU/min, which corresponds well to the dose used by Mackenzie et al. (121)-i.e., 100 IU in 500 ml of fluid at 12 drops/min, with no difference in effect produced when this dose was doubled. Antibiotic prophylaxis is used to some extent in connexion with both first- and second-trimester abortions, but few authors seem convinced of its effectiveness. In a comparative study of saline abor- tions, Mackenzie et al. (121) gave prophylactic anti- biotics to 110 patients, 56 not receiving prophylaxis. There was fever in 4 of the former and 9 of the latter. Sterilization in combination with abortion operation The simultaneous operation is claimed to raise the, mortality rate above the rate associated with abortion only. In 1969 there were 17 deaths asso- ciated with legal abortion in the United Kingdom; 12 of these were women sterilized at the time of abor- tion. That year 35 % of the women aborted were also sterilized (124). Olsen et al. (6) reported 8 abortion deaths from Denmark during 1961-66, 4 of which were also associated with sterilization. Hystero- tomy and sterilization (responsible for 3 of the fatal cases) accounted for 24% of abortions during that time. Huntingford (14) analysed the 17 deaths in the United Kingdom in 1969 regarding age and gestational stage and found that these factors are much less important than is the connexion with sterilization. The mortality from abortion alone is 1/100 000 and from abortion with sterilization 11/100 000. A way to reduce this mortality is pointed out by Steptoe (125), who performed laparoscopic steriliza- tion at the time of uterine aspiration in 101 cases, with apparently much less operation trauma. Vagi- nal tubal ligation in connexion with uterine aspira- tion was also advocated by Sogolow (126), but he had in his 127 cases a fairly high complication rate: 9.9% with unspecified infections and 4.1 % bleeding more than 800 ml at operation. Tietze & Lewit (15) found a two- to three-fold increase in morbidity in healthy patients with and without sterilization, when uterine aspiration or dilatation and curettage were combined with tubal ligation, but no increase when saline or hysterotomy was chosen. In 266 patients uterine aspiration was combined with sterilization via the laparoscope with- out an increase in morbidity. From the British data on mortality from abortion in combination with sterilization, Huntingford draws the conclusion that the two operations should always be performed on separate occasions (14). However, judging from the JPSA study, such a general conclusion is not justified. The combination of uterine aspiration or dilatation and curettage with abdominal tubal ligation certainly gives an increase in the complication rate compared with abortion only, but as far as all other combinations are concerned no pronounced increase is evident. A definite answer to this question has to await further analysis, which must take into account mortality and morbidity caused by two surgical interventions made separately in the same patient. DISCUSSION A study of the literature reveals that there is a wide range of opinions on the incidence and defini- tion of complications after induced abortion. To overcome the current disparity of views, complica- tions should be defined in a uniform way and uniform criteria should be established for follow-up reporting. Knowledge on late somatic sequelae is particularly scarce. Very few have actually been proved to be harmful effects resulting from the procedure per se and not from other interfering factors. Prospective studies on fertility are difficult to perform, owing to the high drop-out rates expected among patients and to the small number of women with a history of induced abortion that can be expected to plan a pregnancy during the years immediately following the abortion. Retrospective studies, carefully de- signed and with matched controls, could probably yield valuable information on the incidence of infer- tility, prematurity, and events such as extrauterine pregnancy in women with a history of abortion. Designs for such studies have been worked out by 133 KARIN G. B. EDSTROM the Task Force on Sequelae and Complications of Induced Abortion, within the WHO Expanded Pro- gramme of Research Development and Research Training in Human Reproduction. The studies will be performed in several countries and it is to be hoped that they will yield valid information within a few years on the role of the abortion operation in the etiology of, for instance, the higher prematurity rate in aborted women. As to techniques for the interruption of preg- nancy, it seems clear that most investigators consider uterine aspiration to be the method of choice during the first trimester. It is more difficult to recommend a certain method for second-trimester abortions. Instillation of prostaglandin compounds in utero is regarded by many as being a promising method. This method is at present under investigation by the Task Force on the Use of Prostaglandins for the Regulation of Fertility. A number of other aspects of abortion care, such as inpatient versus outpatient care and the type of anaesthesia used, have been well elucidated in large numbers of patients. However, these data reflect mainly the effects of liberally performed abortions in countries with a high technical standard and a fairly healthy population. One cannot use these data to predict the complication rate in a country that is starting to perform induced abortions on a large scale in a population with lower levels of health and nutritional status. Investigations into these problems are also within the scope of the above-mentioned task forces. ACKNOWLEDGEMENTS This paper was prepared during a consultantship with the World Health Organization, Geneva. The author alone is responsible for the views expressed in the article, which does not represent the decisions or stated policy of the World Health Organization. The author also acknowledges the valuable assistance of Miss Beverly Crowther, WHO, Geneva, in the prepa- ration of the material. RItSUMI COMPLICATIONS IMMEDIATES ET SEQUELLES TARDIVES DE L AVORTEMENT PROVOQUE: EXAMEN DE LA LITTERATURE Les ouvrages traitant des techniques abortives et des complications de l'avortement provoqu6 sont tres abondants mais la definition de ces complications est extremement variable, soit en raison de l'opinion des auteurs a l'egard des techniques utilisees, soit en raison d'autres facteurs d'influence. En outre, les taux de complications varient aussi selon les methodes employees pour la collecte des donn6es et les possibilites d'avor- tement legal offertes par chaque pays. C'est dire que le lecteur qui souhaite connaitre les risques relatifs des diverses m6thodes et des avortements l6gaux a bien de la peine A y voir clair. Dans la presente etude de la litt6rature consacree a ce sujet, nous avons tente, d'une part, de mettre en evidence les informations valables existantes et, d'autre part, d'indiquer les principaux domaines oiu des recherches sont encore necessaires. Les taux nationaux de mortalite et de morbidite montrent que les pays qui comptent un grand nombre d'avortements et en particulier d'avortements au cours des trois premiers mois de la grossesse ont un taux de complications relativement faible. Des etudes plus specifiques font apparaitre que les facteurs qui influent le plus sur les taux de complications sont le stade de la grossesse, 1'etat de sante de la mere, la m6thode employee et l'association de l'avortement avec la ligature des trompes. En ce qui concerne les interruptions de gros- sesse pratiqu6es au cours des trois premiers mois, c'est la technique de l'aspiration ut6rine qui est la moins traumatisante, surtout lorsqu'elle est pratiquee tres t6t au moyen d'une fine canule et sans dilatation. Pour ce qui est des interruptions de grossesse au cours du second trimestre, les instillations de solutions hyper- toniques, de rivanol, ou - mieux encore peut-etre - de prostaglandines semblent entrainer moins de risque que les autres techniques. Les complications graves avec les solutions salines hypertoniques sont tres rares et peuvent 8tre presque completement evitees si l'on utilise une bonne technique d'instillation et si l'on observe les precautions voulues. Les facteurs tels que l'age, la parit6, les services offerts, et l'anesth6sie semblent avoir moins d'importance. L'existence de sequelles a long terme a fait l'objet de tres nombreuses etudes mais, par rapport au nombre 134 ABORTION 135 total des avortements pratiques, celui des donnees disponibles est tres peu eleve. I1 semble qu'il y ait une relation entre l'avortement provoque et la naissance ulterieure de nouveau-nes .de poids faible mais jusqu'ici, on n'a pas demontre si les naissances de poids faible etaient liees a l'operation d'interruption de grossesse ou a quelque autre facteur egalement courant chez les interess6es. En general, les autres sequelles etudiees sont egalement associees aux grossesses ulterieures. On mentionne des complications au cours de la grossesse et au moment de l'accouchement, une prolongation du travail, et une augmentation de la mortalite feetale, mais la relation entre ces faits et les avortements provoqu6s n'a pas ete clairement etablie. Il en est de meme en ce qui concerne l'infecondite et les troubles menstruels. Les effets psy- chologiques de l'interruption de grossesse ne sont pas examines dans le present document. La variabilite des attitudes a l'egard de l'avortement dans les divers pays joue, a cet egard, un role essentiel et le probleme se complique encore du fait des fluctuations continuelles d'opinion. Le domaine de recherche qui reclame le plus d'efforts est celui des sequelles A long terme. Pour 6tablir le r6le etiologique des operations d'avortement, les etudes doivent porter sur de larges groupes de femmes avort6es et sur des groupes temoins bien definis de maniere que d'autres facteurs soient pris en compte notamment l'etat de sante des interess6es, leur age et leur parite, et leur situation socio-economique. Pour ce qui est des complications immediates de l'avortement provoque, on dispose de bonnes donnees recueillies en Europe et aux Etats-Unis d'Amerique mais il n'est pas possible de predire, sur la base de ces donnees, les effets que pourrait avoir une augmentation subite du nombre des avortements provoques, dans une population moins bien nutrie et moins bien portante. L'Organisation mondiale de la Sante soutiendra plusieurs recherches dans ce domaine, faites dans diverses regions. Le Groupe de travail sur les sequelles et les complications de l'avortement provoque a deja concu 5 etudes, et une sous-section de ce groupe s'emploie A elucider les sequelles psychologiques et psycho-sociales eventuelles de l'interruption de grossesse. REFERENCES 1. DAVID, H. P. Family planning and abortion in the socialist countries of central and eastern Europe. New York, Population Council, 1970. 2. TIETZE, C. Somatic consequences of abortion. In: Newman, S. H., Beck, M. B., & Lewit, S., ed. 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