Risk of spontaneous abortion following induced abortion is only increased with short interpregnancy interval.

We set out to study the risk of spontaneous abortion following a first trimester induced abortion as a function of the interpregnancy interval between two pregnancies. The cohort study is based on the following databases: Danish national registries: the Medical Birth Registry (MBR), the Hospital Discharge Registry (HDR), and the induced Abortion Registry (IAR). All primigravid women in the time period from 1980 to 1982 were identified in the MBR, the HDR and the IAR. A total of 15 727 women who terminated the pregnancy with a first trimester induced abortion were selected as the induced abortion cohort, and 46 026 women who did not terminate the pregnancy with an induced abortion constituted the control cohort. By register linkage all subsequent pregnancies which were not terminated by induced abortion were identified from 1980 to 1994. Only women who had a non-terminated pregnancy following the index pregnancy were selected. Women whose first pregnancy was terminated following a first trimester induced abortion had a risk of spontaneous abortion of 11.0% vs. 9.4% in the control cohort. This relative difference of 1.17 was not statistically significant in logistic regression analyses. An increased risk was only found for women who had an interpregnancy interval of less than 3 months (OR=4.06, 95% C.I.=1.98-8.31). The abortion method, vacuum aspiration with dilatation or evacuation with dilatation did not modify this elevated risk. Overall the study did not show an increased risk of spontaneous abortion following one or more induced abortions, except for women with a short interpregnancy interval between an induced abortion and a subsequent pregnancy. We recommend women who have a first trimester induced abortion be advised to wait at least 3-6 months before trying to become pregnant again.     

Induced abortion and subsequent pregnancy duration

OBJECTIVE: To examine whether induced abortion influences subsequent pregnancy duration. METHODS: Women who had their first pregnancies during 1980, 1981, and 1982 were identified in three Danish national registries. A total of 15,727 women whose pregnancies were terminated by first-trimester induced abortions were compared with 46,026 whose pregnancies were not terminated by induced abortions. All subsequent pregnancies until 1994 were identified by register linkage. RESULTS: Preterm and post-term singleton live births were more frequent in women with one, two, or more previous induced abortions. After adjusting for potential confounders and stratifying by gravidity, the odds ratios of preterm singleton live births in women with one, two, or more previous induced abortions were 1.89 (95% confidence interval [CI] 1.70, 2.11), 2.66 (95% CI 2.09, 3.37), and 2.03 (95% CI 1.29, 3.19), respectively. Odds ratios of post-term singleton live births in women with one, two, or more previous induced abortions were 1.34 (95% CI 1.24, 1.44), 1.50 (95% CI 1.26, 1.78), and 1.58 (95% CI 1.09, 2.28), respectively. CONCLUSION: The study showed an increase in preterm and post-term pregnancies after induced abortions. The risk of post-term delivery was high regardless of the interpregnancy interval, whereas increased risk of preterm delivery was seen mainly when interpregnancy intervals were longer than 12 months.     

Induced abortion and duration of third stage labour in a subsequent pregnancy.

We set out to evaluate the impact of first trimester induced abortion on the duration of third stage labour and related complications in a subsequent pregnancy. The study was conducted in Shanghai city at 15 general hospitals (or maternity and infant health institutes) from November 1993 to March 1998. We identified all nulliparae who came for antenatal care within the first 63 days of pregnancy (2953); the women were divided into two cohorts according to their previous history of first trimester induced abortion. After enrollment, the women were interviewed five times from recruitment until 42 days after delivery. We included in the study all 1363 women who had a singleton vaginal live birth. Of these women, 703 were primigravida (non-exposed), 534 had had one previous first trimester induced abortion, and 126 women had had two or more first trimester induced abortions. The duration of third stage labour in minutes was longer in women with one or more previous induced abortions (mean=7.32 minutes) compared with primigravid women (mean=6.79 minutes). Prolonged third stage labour (>30 minutes) following one or more induced abortions was seen for 3.4% versus 1.0% in primigravid women. After adjusting for a number of potential confounders, women with one or more previous first trimester induced abortions had an odds ratio of prolonged third stage labour of 2.59 (95%C.I.=1.06-6.37) compared with primigravida, especially after an interpregnancy interval of more than 6 months (OR=3.24, 95%C.I.=1.29-8.13). The odds ratio of prolonged third stage labour was 3.14 (95%C.I.=1.22-8.09) if gestational age at the time of the induced abortion exceeded 49 days. Women with a first trimester induced abortion had no significantly increased risk of postpartum haemorrhage or retained placenta. It was concluded that a history of one or more first trimester induced abortions was related to an increased risk of prolonged third stage labour in the following pregnancy, particularly if the induced abortion was performed after 49 days of gestation.     

Pregnancy complications following legally induced abortion with special reference to abortion technique.

A study of 576 pregnant women, whose previous pregnancy had been terminated by legally induced abortion, has shown that the rate of pregnancy and delivery complications could not be correlated with the interval between the abortion and the subsequent pregnancy, nor with the gestational age at the time of abortion, nor the number of previous induced abortions. Neither was the abortion technique found to correlate with the frequency of complications in a subsequent pregnancy. It was found, however, that more infants with a birth weight below 2 501 grams were born to women whose cervical canal during abortion had been dilated more than 12 mm, and by women who had been submitted to récurettage. The latter group also demonstrated a higher frequency of retained placenta or placental tissue.     

Spontaneous abortion: a prospective cohort study of younger women from the general population in Denmark. Validation, occurrence and risk determinants

OBJECTIVE: To assess the occurrence of spontaneous abortion, comparing two different data sources. To estimate the rate of spontaneous abortion over a 2-year period, and examine potential predictors of the risk for incident spontaneous abortion. METHODS: We used interview data from a population-based prospective cohort study comprising 11,088 women and data from a linkage of the cohort with the Hospital Discharge Register to compare spontaneous abortions as reported in the interview with those identified in the register. Based on interview data, we estimated the rate of spontaneous abortion during the two-year follow-up. Finally, risk determinants for incident spontaneous abortion were analyzed by means of logistic regression. RESULTS: A total of 654 spontaneous abortions before enrolment in the study were reported by the women compared to 531 abortions found in the register. More than 80% of the spontaneous abortions identified from both sources were recorded in the same year. During follow-up a total of 20.9% of pregnancies intended to be carried to term ended as a spontaneous abortion. In the risk factor analysis, we found that previous spontaneous abortion, being single, never having used oral contraceptives, and use of intrauterine device were associated with increased risk of subsequent spontaneous abortion. In addition, it was indicated that a short interpregnancy interval following a spontaneous abortion may confer an increased risk of abortion in the subsequent pregnancy. CONCLUSION: We found a high rate of spontaneous abortion in the present study and an acceptable agreement between information obtained by interview and register information. More than 25% of the spontaneous abortions were only reported by the women, and this could not be explained by erroneously reported induced abortions, and may be early, nonhospitalized abortions. We confirm that number of previous spontaneous abortions is a strong determinant, and our data may also indicate a role of previous contraceptive habits. A role of the length of interpregnancy interval in the risk of spontaneous abortion cannot be ruled out.     

Are complications after an induced abortion associated with reproductive failures in a subsequent pregnancy?

BACKGROUND: We have previously shown that induced abortions result in a slightly increased risk of spontaneous abortion and preterm delivery in subsequent pregnancies. Danish records show that approximately 4% of women who undergo surgically induced abortions have complications related to the procedure. We examined whether it was women who had the short-term complications that carried an excess risk of spontaneous abortion and preterm delivery in the subsequent pregnancy. METHODS: Two cohorts of women who had had an induced abortion and a subsequent pregnancy were followed. The cohort with no reported complications comprised 12,972 women, and the cohort with complications 605 women. RESULTS: The cohort with complications did not have more spontaneous abortions or preterm births. They did, however, have a higher risk of stillbirth, mainly seen in women whose induced abortion had been complicated by an infection. CONCLUSION: Most of the women who had had an induced abortion with reported complications did, however, carry a subsequent pregnancy to term with no more complications than other women of similar parity and age.     

Pregnancy outcome following recurrent spontaneous abortions

OBJECTIVE: The purpose of the present study was to examine the association between spontaneous consecutive recurrent abortions and pregnancy complications such as hypertensive disorders, abruptio placenta, intrauterine growth restriction and cesarean section (CS) in the subsequent pregnancy. METHODS: A population-based study comparing all singleton pregnancies in women with and without two or more consecutive recurrent abortions was conducted. Deliveries occurred during the years 1988-2002. Stratified analysis, using a multiple logistic regression model was performed to control for confounders. RESULTS: During the study period 154,294 singleton deliveries occurred, with 4.9% in patients with history of recurrent consecutive abortions. Using a multivariate analysis, with backward elimination, the following complications were significantly associated with recurrent abortions-advanced maternal age, cervical incompetence, previous CS, diabetes mellitus, hypertensive disorders, placenta previa and abruptio placenta, mal-presentations and PROM. A higher rate of CS was found among patients with previous spontaneous consecutive recurrent abortions (15.9% versus 10.9%; OR = 1.6; 95% CI, 1.5-1.7; P < 0.001). Another multivariate analysis was performed, with CS as the outcome variable, controlling for confounders such as placenta previa, abruptio placenta, diabetes mellitus, hypertensive disorders, previous CS, mal-presentations, fertility treatments and PROM. A history of recurrent abortion was found as an independent risk factor for CS (OR = 1.2; 95% CI, 1.1-1.3; P < 0.001). About 58 cases of inherited thrombophilia were found between the years 2000-2002. These cases were significantly more common in the recurrent abortion as compared to the comparison group (1.2% versus 0.1%; OR = 11.1; 95% CI, 6.5-18.9; P < 0.001). CONCLUSION: A significant association exists between consecutive recurrent abortions and pregnancy complications such as placental abruption, hypertensive disorders and CS. This association persists after controlling for variables considered to coexist with recurrent abortions. Careful surveillance is required in pregnancies following recurrent abortions, for early detection of possible complications.     

Placenta previa in singleton and twin births in the United States, 1989 through 1998: a comparison of risk factor profiles and associated conditions

OBJECTIVE: The purpose of this study was to compare risk factor profiles for placenta previa between singleton and twin live births. STUDY DESIGN: This cohort study was based on United States natality data files (1989 through 1998) and comprised 37,956,020 singleton births and 961,578 twin births. Women who were diagnosed with placenta previa were included only if they were delivered by cesarean delivery. Risk factors for placenta previa that were examined included sociodemographic (age, gravidity, education, marital status, and race), behavioral (prenatal care, smoking, and alcohol use), previous preterm birth, and medical and obstetric factors. Effect modification between maternal age and gravidity and the dose-response relationship with number of cigarettes smoked/day on placenta previa risk were also evaluated. RESULTS: The rate of placenta previa was 40% higher among twin births (3.9 per 1,000 live births, n = 3,793 births) than among singleton births (2.8 per 1,000 live births, n = 104,754 births). Comparison of risk factors for placenta previa between the singleton and twin births revealed fairly similar risk factor profiles. Compared with primigravid women <20 years old, the risk for placenta previa increased by advancing age and by increasing number of pregnancies among both singleton and twin births. The number of cigarettes smoked per day also showed a dose-response trend for placenta previa risk in the two groups. CONCLUSION: The increased rate of placenta previa among twin births underscores the need to monitor carefully such pregnancies with heightened suspicion and awareness for the development of this condition.     

Legal abortion and placenta previa

Legal abortion has been postulated to be a risk factor for placenta previa in subsequent pregnancies. To examine this hypothesis, we analyzed the deliveries of 28,665 women. We identified 68 women who had had placenta previa and compared their obstetric histories with those of 68 controls randomly selected from the same group of deliveries. The crude risk ratio for women with a history of one or more legal abortions was 1.4 (95% confidence interval, 0.5 to 3.6; p greater than 0.05). Standardizing the crude risk ratio for the effects of age and gravidity reduced the risk ratio to 1.1 (95% confidence interval, 0.4 to 2.8). In this predominantly black population legal abortion does not appear to have a significant association with placenta previa in subsequent pregnancies.     

The association between previous single first trimester abortion and pregnancy outcome in nulliparous women

Objective: To determine the association between single previous abortion and pregnancy outcome in nulliparous women.

Methods: A retrospective cohort study of all nulliparous women who delivered in a university-affiliated tertiary hospital (2009–2014). Pregnancy outcome of women with single previous first trimester abortion (study group) was compared to those of primigravida (control group).

Results: Of the 44?371 deliveries during the study period, 14?498 (32.6%) were of nulliparous women, of them 1501 (10.3%) had single previous abortion (<13 weeks). Except for a higher rate of diabetes mellitus in the study group (6.1 versus 4.4%, p?=?0.003), no differences were found between the groups regarding pregnancy complications. In multivariate analysis, previous single abortion was independently associated with induction of labor (OR?=?1.31, 95%C.I 1.04–1.63, p?=?0.01), cesarean section (OR?=?1.38, 95%C.I 1.18–1.60, p?<?0.001) and retained placenta (OR?=?1.29, 95%C.I 1.03–1.61, p?=?0.02). Among nulliparous women with previous single abortion no difference in pregnancy outcome was observed between those with previous induced termination of pregnancy and spontaneous abortion, except for increased risk for retained placenta in those with previous spontaneous abortion.

Conclusion: Single early previous abortion in nulliparous women was associated with higher rate of induction of labor, cesarean section and retained placenta compared to primigravida women.     

Previous history of surgically induced abortion and complications of the third stage of labour in subsequent normal vaginal deliveries

Objective. To estimate the risk of complications of the third stage of labour needing manual revision of uterine cavity or curettage in deliveries following one or multiple induced abortions in nulliparous women who had singleton live births in Estonia in 1994–2002.

Methods. Registry study using the data from the Estonian medical birth registry: 32,652 women had not had any abortions, 7333 women had had one and 2383 women had had two or more surgically induced abortions before their first delivery. Multiple logistic regression analysis was performed to estimate crude odds ratios (OR), adjusted ORs and their 95% confidence intervals, with women having had no abortions as the reference group. Adjustment was made for maternal age, sex and weight of infant, labour induction/augmentation.

Results. In the single abortion group, the crude OR was 1.25 (95% confidence intervals (CI) 1.12–1.40), the adjusted OR was 1.23 (95% CI 1.10–1.38); in the multiple abortion group the crude OR was 1.28 (95% CI 1.06–1.53), the adjusted OR was 1.24 (95% CI 1.03–1.49).

Conclusions. Our findings suggest a positive association between one or more first trimester abortion(s) and the risk of complications in the third stage of labour in subsequent singleton delivery.     

The impact of interpregnancy interval and previous preterm birth on the subsequent risk of preterm birth

OBJECTIVE: To examine the impact of the interpregnancy interval and a previous preterm birth on the subsequent risk of a preterm birth. METHODS: A retrospective analysis was conducted on a group of 4072 women who had at least two consecutive births, excluding multiple gestation, fetal anomalies, cervical incompetence, and stillbirth. Multivariate logistic regression was used to investigate the association between interpregnancy interval, preterm birth of the first child in the pair (index pregnancy), and the risk of a preterm birth of the second child in the pair (outcome pregnancy). RESULTS: Women with interpregnancy intervals of less than 12 months (odds ratio [OR] 1.3; 95% confidence interval [CI] 1.0-1.7) were at increased risks of preterm birth with the outcome pregnancy. Furthermore, there was an increased risk for a subsequent preterm birth in women who had a preterm birth in the index pregnancy (OR 4.2; 95% CI 3.0-6.0). The risk decreased as the interpregnancy interval increased, with a relatively low risk at 18 to 48 months; subsequently, it increased sharply. In contrast, women who had delivered their previous infants at term carried an increased risk of preterm birth with the outcome pregnancy only if the interval was less than 6 months. CONCLUSION: A difference was found in the impact of the interpregnancy interval on the subsequent risk of preterm birth between women with a prior preterm birth and those who previously delivered an infant at term.     

Pregnancy outcome after in utero exposure to itraconazole: a prospective cohort study

OBJECTIVE: This study was undertaken to determine whether itraconazole use during the first trimester of pregnancy was associated with increased risks of major malformations, spontaneous abortions, premature deliveries, and neonatal complications. STUDY DESIGN: In a prospective cohort study pregnant women exposed to oral itraconazole were matched with control subjects not exposed to any known teratogens. Primary outcome was the rate of major malformations. Secondary outcomes were live birth rate, rates of spontaneous abortion and therapeutic abortion, gestational age at delivery, birth weight, and neonatal complications. RESULTS: A total of 229 women exposed to itraconazole were reported to the manufacturer, 198 of whom used the drug during the first trimester of pregnancy. The rate of major malformations in the study group (156 live births) was 3.2%, compared with 4.8% in the control group (187 live births; relative risk, 0.67; 95% confidence interval, 0. 23-1.95). The rate of any pregnancy loss was higher in the exposed group (relative risk, 1.75; 95% confidence interval, 1.47-2.09). Birth weight was lower in the itraconazole group, although that difference may not be clinically significant. Gestational age at birth, rate of preterm delivery, Apgar scores at 1 and 5 minutes, and neonatal complications were comparable between the groups. CONCLUSION: Our study supports the hypothesis that the use of itraconazole during pregnancy is safe. Further surveillance and reporting of pregnancy outcomes will help to support this conclusion.     

Spontaneous abortion after amniocentesis in women with a history of spontaneous abortion

The incidence of spontaneous abortion after amniocentesis (19 to 28 weeks gestation) in women who have had previous spontaneous abortions is compared with the rate in women who have not had previous spontaneous abortions. The outcome of the pregnancy after amniocentesis and the previous history of spontaneous abortion is reported for 691 pregnancies. The rate of spontaneous abortion after amniocentesis was found to be significantly higher in women who had one or more previous spontaneous abortions, 12/238 (5 per cent), than in women who did not, 6/453 (1.3 per cent). In women who reported two or more previous spontaneous abortions, the rate was 7/81 (8.6 per cent). No statistically significant effect of maternal age or gravidity was detected. The incidence of spontaneous abortion after amniocentesis was greater in the three weeks following the procedure (three for each of the three weeks) than in the subsequent seven weeks (nine for seven weeks).     

Pregnancy-associated mortality after birth, spontaneous abortion, or induced abortion in Finland, 1987-2000

OBJECTIVE: To test the hypothesis that pregnant and recently pregnant women enjoy a "healthy pregnant women effect," we compared the all natural cause mortality rates for women who were pregnant or within 1 year of pregnancy termination with all other women of reproductive age. STUDY DESIGN: This is a population-based, retrospective cohort study from Finland for a 14-year period, 1987 to 2000. Information on all deaths of women aged 15 to 49 years in Finland (n=15,823) was received from the Cause-of-Death Register and linked to the Medical Birth Register (n=865,988 live births and stillbirths), the Register on Induced Abortions (n=156,789 induced abortions), and the Hospital Discharge Register (n=118,490 spontaneous abortions) to identify pregnancy-associated deaths (n=419). RESULTS: The age-adjusted mortality rate for women during pregnancy and within 1 year of pregnancy termination was 36.7 deaths per 100,000 pregnancies, which was significantly lower than the mortality rate among nonpregnant women, 57.0 per 100,000 person-years (relative risk [RR] 0.64, 95% CI 0.58-0.71). The mortality was lower after a birth (28.2/100,000) than after a spontaneous (51.9/100,000) or induced abortion (83.1/100,000). We observed a significant increase in the risk of death from cerebrovascular diseases after delivery among women aged 15 to 24 years (RR 4.08, 95% CI 1.58-10.55). CONCLUSION: Our study supports the healthy pregnant woman effect for all pregnancies, including those not ending in births.     

Abortion procedures in a tertiary care institution in India.

OBJECTIVE: To determine the complications rate of termination of pregnancy (TOP) and the risk factors for complications following TOP. METHODS: Retrospective observational study of the records of 1287 women who underwent TOP in the Department of Obstetrics and Gynaecology of the Postgraduate Institute of Medical Education and Research, Chandigarh, India, between 1997 and 2001. First-trimester abortion was performed in 1088 women (85%) and second-trimester abortion in 199 women (15%). Most women (76%) were aged between 26 and 30 years; they were educated and requested TOP primarily to limit the number of their children or to space their births. A malformed fetus was the indication for TOP in 5.9% cases, and 16% of the women had medical disorders associated with the pregnancy. Suction evacuation was the method of choice for first-trimester abortion (88%); dinoprostone gel and extra-amniotic saline solution plus oxytocin infusion were the primary methods (71%) for second-trimester abortion. RESULTS: Uterine perforation occurred in 1 patient (0.09%) after a first-trimester abortion. The total rate of complications was 3.79% after first-trimester and 4.0% after second-trimester abortions. Excessive hemorrhage and retained placenta were chief complications associated with second-trimester abortion. Incomplete abortion (1.5%) and minor infection were seen in 2.3% patients. The rate of complications was higher among parous women. Postabortion insertion of a CuT intrauterine device increased the need for a second course of antibiotics. CONCLUSION: Termination of pregnancy is safe if adequate care is taken while performing the procedure.     

Danish National IVF Registry 1994 and 1995. Treatment, pregnancy outcome and complications during pregnancy

SUBJECT: Data from the compulsory Danish National IVF Registry from 1994 and 1995 regarding treatments, abortions and complications following assisted reproductive technologies. METHODS: Data were generated through registries and compared to pregnancies in Denmark in 1995. Those pregnancies that resulted in a delivery were compared to a matched control group. RESULTS: In 1994 and 1995 5219 women were treated in 9471 initiated cycles. The numbers increased over the period. The overall delivery rate per initiated cycle was 19%, egg donation 24%, IVF 20%, ICSI 16% and frozen egg replacement 10%. The rates increased over the period. The rate of spontaneous abortions was highest for ICSI (25%) and egg donation (27%). For IVF and ICSI the birth rates per transfer of 1 embryo was 13, 1%, 2 embryos 25, 4%, 3 embryos 25, 8% and 4 or more 3, 8%. Transfer of 2 embryos resulted in 75% singleton, 25% twin and 0.2% triplet deliveries. After transfer of 3 embryos the corresponding rates were 68%, 29% and 4%. No quadruplet deliveries occurred. Totally, 1.4% reported complications to the treatment, the most frequent being ovarian hyperstimulation syndrome. In the study group 5.8% of the women who gave birth were diagnosed with imminent abortion vs. 3.0% in the control group (OR 1.98, CI 1.41-2.78). CONCLUSIONS: Transfer of three embryos did not result in higher pregnancy rates as compared to transfer of two embryos. The first data from the Danish IVF Registry support data from other registries regarding treatment, pregnancy outcome and complications during pregnancy.     

Manual removal of the placenta--a case control study

The aim of this study was to determine the incidence and complications related to manual removal of the placenta in a regional hospital in Australia. The study was carried out at the Goulburn Valley Base Hospital in Shepparton. The hospital medical records were reviewed from 1992 to 1999. A total of 3734 singleton live vaginal deliveries took place during the 7-year study period. The placenta was removed manually in 114 women (3%). For a control group, a series of 113 women who had singleton live vaginal deliveries from the same period were chosen at random. The case and control groups were similar in age, parity, and gravidity. A previous history of retained placenta and a history of preterm delivery in the current pregnancy were significantly related to retained placenta (OR 9.8 [95% CI 1.1-85.5] and OR 5.6 [95% CI 1.1-26.8], respectively). The cases received significantly more blood transfusions than the control group (13% versus 0%). Decreased maternal age was also significantly related to retained placenta. There were also more post-delivery dilatation and curettage (D&C) operations and diagnosis of endomyometritis in the case group. However, these differences were not statistically significant. One woman, in the case group, had to have a hysterectomy due to placenta accreta.