Spontaneous foetal losses in women using different contraceptives around the time of conception

Lifetime Prevalence of Abortion and Risk Factors in Women: Evidence from a Cohort Study

BACKGROUND

10-20% of pregnancies end due to spontaneous abortions. In recent years, nondocumentary evidence has been indicative of an increase in the prevalence of nonspontaneous abortions in Iran, especially in the Kurdish regions. The aim of this study is to assess the lifetime prevalence of spontaneous abortions and factors affecting spontaneous abortion in women 35-65 years old.

METHOD

Data from the recruitment phase of Ravansar Non-Communicable Disease (RaNCD) cohort study was used. All of the 4831 married women 35-65 years old and with history of pregnancy were included in this study. In order to determine the abortion ratio, the number of abortions was divided by the number of live births, and multiple logistic regression analysis was applied to determine associated factors affecting abortion.

RESULTS

About 25.7% of women had a history of spontaneous abortion. The abortion ratio in women was 0.10. The abortion ratio in women with secondary education, first pregnancy and marriage age at ≥26, socioeconomic condition, and hyperthyroid and diabetes was high while the abortion ratio of women with high physical activity and BMI < 18.9 or residents of rural area was low. After assessing the effective variables, it was found that women with high blood pressure have 63% less odds for nonspontaneous abortion, which is statistically significant (p value < 0.05).

CONCLUSION

Considering the effect of factors such as level of education, older age at the first marriage, and age at the first pregnancy on increased chance of spontaneous abortion, measures should be taken to take more care for these people.

Pregravid Oral Contraceptive Use and the Risk of Preterm Birth, Low Birth Weight, and Spontaneous Abortion: A Systematic Review and Meta-Analysis

Background: Although oral contraceptives (OCs) have been widely used by women of childbearing age, their influence on pregnancy and birth outcomes, such as preterm birth (PB), low birth weight (LBW), and spontaneous abortion (SAB), is unclear. The aim of this systemic review was to assess these complications in women who had used OCs before pregnancy compared with those in a control group. Materials and Methods: The databases of PubMed, EMBASE, and Web of Science were searched up to December 2018. We included studies where the primary outcome was the risk of PB, LBW, and SAB in women with pregravid OCs use compared with the control group. Odds ratio (OR) value was calculated to assess the risk. Results: Eighteen studies were included in the systematic review, and a total of 148,406 subjects from 7 studies were pooled for the meta-analysis. Results showed that the risk of PB was slightly higher in the exposed group (OR = 1.17, 95% confidence interval [CI] = 1.07-1.27, p = 0.0005); however, there was a lower risk for SAB compared with the control group (OR = 0.63, 95% CI = 0.41-0.96, p = 0.03). No significant difference was found in the incidence of LBW (OR = 1.36, 95% CI = 0.92-2.02, p = 0.12). Conclusions: This systematic review and meta-analysis demonstrated a higher risk for PB and a lower risk for SAB in women with previous ORs use, whereas no association was found between ORs use and LBW risk.

History of oral contraceptive use and risk of spontaneous abortion

PURPOSE

To examine the association between pregravid oral contraceptive (OC) use and spontaneous abortion (SAB).

METHODS

In an Internet-based preconception cohort study of 4862 Danish pregnancy planners, we used Cox proportional hazards models to estimate adjusted hazard ratios and 95% confidence intervals (CIs) for the association between OC use and SAB. We controlled for maternal age, physical activity, parity, education, alcohol and caffeine consumption, body mass index, and smoking.

RESULTS

Compared with women who discontinued OCs >1 year before conception, HRs were 0.95 (95% confidence interval (CI) = 0.77-1.17), 0.99 (95% CI = 0.82-1.19), and 0.80 (95% CI = 0.60-1.06) for women who discontinued OCs 7-12, 2-6, and 0-1 months before conception, respectively. Compared with less than 4 years of OC use, HRs for 4-7, 8-11, and 12 years or more of OC use were 1.05 (95% CI = 0.80-1.37), 0.92 (95% CI = 0.71-1.19), and 0.88 (95% CI = 0.65-1.19), respectively. Dose of estrogen and generation of progestin were not materially associated with SAB risk.

CONCLUSIONS

We found no evidence that pregravid OC use is associated with an increase in SAB. Use within 1 month of conception was associated with a slightly lower risk of SAB, but this may be due to increased reproductive fitness in women who conceive quickly after discontinuation of OCs.

Maternal use of oral contraceptives and risk of fetal death

Intrauterine exposure to artificial sex hormones such as oral contraceptives may be associated with an increased risk of fetal death. Between 1996 and 2002, a total of 92 719 women were recruited to The Danish National Birth Cohort and interviewed about exposures during pregnancy. Outcome of pregnancy was identified through linkage to the Civil Registration System and the National Discharge Registry. The authors analysed the risk of fetal death after recruitment to the cohort by using proportional hazards regression models with gestational age as the underlying time scale. In total, 1102 (1.2%) women took oral contraceptives during pregnancy. Use of combined oestrogen and progesterone oral contraceptives (COC) or progesterone-only oral contraceptives (POC) during pregnancy was not associated with increased hazard ratios of fetal death compared with non-users, HR 1.01 [95% CI 0.71, 1.45] and HR 1.37 [95% CI 0.65, 2.89] respectively. Neither use of COC nor POC prior to pregnancy was associated with fetal death. Stratification by maternal age and smoking showed elevated risks of fetal death for women <30 years and smokers using oral contraception during pregnancy, but the interactions were not significant. In conclusion, there was no evidence that oral contraceptive use before or during pregnancy is associated with an increased risk of fetal death.

Clinical significance of morphologic and genetic examination of spontaneously aborted embryos

PROBLEM

In families with a history of multiple pregnancy losses, the prognosis of future pregnancies is critically dependent on recognizing an accurate pathogenesis of pregnancy loss.

METHOD OF STUDY

Morphological and genetic evaluation of products of conception provides necessary information for clinicians. Modern molecular cytogenetic techniques such as in situ hybridization and comparative genomic hybridization allow cytogenetic diagnosis even when aborted tissues are nonviable.

RESULTS

Correlation of morphological and cytogenetic findings allows distinction between developmental defects associated with chromosomal syndromes and other pathogenesis such as environmental teratogens, and Mendalian or multifactorial inheritance.

CONCLUSION

Pathologists have the responsibility of ensuring that the answers to questions, such as why the failure occurred or whether there is any increased chance of having an abnormal liveborn infant in a future pregnancy, are obtained and that the information is communicated to the parent's obstetrician, geneticist, and family physician.

Timing of conception and the risk of spontaneous abortion among pregnancies occurring during the use of natural family planning

OBJECTIVE

Our purpose was to ascertain the effects of timing of conception on the risk of spontaneous abortion.

STUDY DESIGN

To assess these effects, women who conceived while using natural family planning were identified in five centers worldwide between 1987 and 1993. Timing of conception was determined from 868 natural family planning charts that recorded day of intercourse and indices of ovulation (cervical mucus peak obtained according to the ovulation method and/or basal body temperature). Conceptions on days - 1 or 0 with respect to the natural family planning estimated day of ovulation were considered to be "optimally timed," and all other conceptions were considered as "non-optimally timed." The rate of spontaneous abortions per 100 pregnancies was examined in relation to timing of conception, ages, reproductive history, and other covariates with bivariate and multivariate statistical methods.

RESULTS

There were 88 spontaneous abortions among 868 pregnancies (10.1%). The spontaneous abortion rate was similar for 361 optimally timed conceptions (9.1%) and 507 non-optimally timed conceptions (10.9%). However, among 171 women who had experienced a spontaneous abortion in a prior pregnancy, the rate of spontaneous abortion in the index pregnancy was significantly higher with non-optimally timed conceptions (22.6%) as compared with optimally timed conceptions (7.3%). This association was not observed among 697 women with no history of pregnancy loss. The adjusted relative risk of spontaneous abortion among women with non-optimally timed conceptions and a history of pregnancy loss was 2.35 (95% confidence intervals 1.42 to 3.89). The excess risk of spontaneous abortion was observed with both preovulatory and postovulatory conceptions.

CONCLUSIONS

Overall, there is no excess risk of spontaneous abortion among the pregnancies conceived during natural family planning use. However, among women with a history of pregnancy loss, there is an increased risk of spontaneous abortion associated with preovulatory or postovulatory delayed conceptions.

Fertility after contraception or abortion

There is a very small correlation, if any, between the prior use of OCs and congenital malformations, including Down's syndrome. There are few, if any, recent reports on masculinization of a female fetus born to a mother who took an OC containing 1 mg of a progestogen during early pregnancy. However, patients suspected of being pregnant and who are desirous of continuing that pregnancy should not continue to take OCs, nor should progestogen withdrawal pregnancy tests be used. Concern still exists regarding the occurrence of congenital abnormalities in babies born to such women. The incidence of postoperative infection after first trimester therapeutic abortion in this country is low. However, increasing numbers of women are undergoing repeated pregnancy terminations, and their risk for subsequent pelvic infections may be multiplied with each succeeding abortion. The incidence of prematurity due to cervical incompetence or surgical infertility after first trimester pregnancy terminations is not increased significantly. Asherman's syndrome may occur after septic therapeutic abortion. The pregnancy rate after treatment of this syndrome is low. The return of menses and the achievement of a pregnancy may be slightly delayed after OCs are discontinued, but the fertility rate is within the normal range by 1 year. The incidence of postpill amenorrhea of greater than 6 months' duration is probably less than 1%. The occurrence of the syndrome does not seem to be related to length of use or type of pill. Patients with prior normal menses as well as those with menstrual abnormalities before use of OCs may develop this syndrome. Patients with normal estrogen and gonadotropin levels usually respond with return of menses and ovulation when treated with clomiphene. The rate for achievement of pregnancy is much lower than that for patients with spontaneous return of menses. The criteria for defining PID or for categorizing its severity are diverse. The incidence of PID is higher among IUD users than among patients taking OCs or using a barrier method. The excess risk of PID among IUD users, with the exception of the first few months after insertion, is related to sexually transmitted diseases and not the IUD. Women with no risk factors for sexually transmitted diseases have little increased risk of PID or infertility associated with IUD use. There appears to be no increased risk of congenital anomalies, altered sex ratio, or early pregnancy loss among spermicide users. All present methods of contraception entail some risk to the patient. The risk of imparied future fertility with the use of any method appears to be low.(ABSTRACT TRUNCATED AT 400 WORDS)

Maternal spermicide use and adverse reproductive outcome: a meta-analysis

A meta-analysis was performed to determine whether the literature provides evidence that periconceptual or postconceptual maternal use of spermicides is detrimental to the developing fetus. Nine studies that investigated teratogenicity met the inclusion criteria. The Mantel-Haenszel summary odds ratio was 1.02 (95% confidence interval = 0.78 to 1.32). The chi 2 analyses was 0.10 for significance from unity (p = 0.748) and 8.73 for homogeneity of effects (p = 0.365). Studies comparing specific abnormalities with other abnormalities also indicated no association (odds ratio = 0.96; 95% confidence interval = 0.72 to 1.28). Studies investigating other adverse events (spontaneous abortion, stillbirth, reduced fetal weight, prematurity, or increased incidence of female births) showed similar negative results. Cohen's d, the overall effect size as determined by Tukey's jackknife method, was -0.001 (95% confidence interval = -0.018 to 0.017). These results indicate that maternal use of spermicides is not associated with adverse fetal outcomes. Meta-analysis adds quantitative support for conclusions from traditional reviews of the subject.

"Proof" of cause and effect in epidemiologic studies: criteria for judgment

A review of epidemiologic criteria for judging cause and effect emphasizes their empirical basis and points to their limitations for establishing "scientific proof." The criteria are applied to a controversy concerning a putative detrimental effect of spermicides on spontaneous abortion and congenital malformations. The criteria indicate a lack of firm evidence for the contention that spermicides have an adverse effect on pregnancy outcome.

Drugs and stillbirth

In a case-control study spanning five years' experience at Group Health Cooperative of Puget Sound, we could demonstrate no plausible association between the use of spermicides, oral contraceptives, Bendectin, or antibiotics prior to conception and the occurrence of 73 nontraumatic stillbirths.

Spontaneous abortion and interpregnancy interval

Analysis of 8972 pregnancies and 5089 interpregnancy intervals, computer-registered over 12 years at the Haguenau Hospital Maternity Department, showed that the length of interpregnancy interval may be considered as a risk factor in spontaneous abortion; this was still true after other important known risk factors, i.e. maternal age, parity, previous spontaneous abortion and contraceptive practice, had been taken into account. However, separate analysis of pregnancies according to whether they occur more or less than 1 year after contraception (if used) had been stopped showed that the relationship between a long interval and spontaneous abortion was only significant for subfertile women who took longer than 1 year to conceive. This supports the hypothesis that the same mechanism is involved in the aetiologies of spontaneous abortion and of difficulty in conceiving.

Spontaneous abortions among women working in the pharmaceutical industry

A register based study was conducted on the pregnancy outcome of female workers in eight Finnish pharmaceutical factories to determine whether they had a higher risk of spontaneous abortion than the general population or matched controls. Information about all female workers who had been employed in the factories during the years 1973 or 1975 (four factories) to 1980 was obtained from the employers. The workers' pregnancy data were collected from the nation wide hospital discharge register and polyclinic data of hospitals from 1973 to 1981. The total number of 1795 pregnancies included 1179 deliveries, 142 spontaneous abortions, and 474 induced abortions. The spontaneous abortion rate (the number of spontaneous abortions X 100, divided by the number of spontaneous abortions plus the number of births) during employment was 10.9% and before/after employment 10.6%. The rate for all the women in the corresponding central hospital districts was 11.3% [corrected] during the study period. A case-control study was also carried out in which the cases were 44 women who had a spontaneous abortion during employment in the pharmaceutical factory. Three age matched female pharmaceutical factory workers who had given birth to a child were chosen as controls for every case. The information about occupational exposures was collected from questionnaires completed by the occupational physician or nurse at the factory. The response rate was 93%. Exposure to chemicals was more common among the cases than among the controls. For methylene chloride, a solvent commonly used in the pharmaceutical industry, the increase in odds ratio of borderline significance (odds ratio 2.3, p = 0.06). In a logistic regression model (which included oestrogen exposure, solvent exposure frequency of the usage, and heavy lifting) the odds ratio was increased for oestrogens (odds ratio 4.2, p = 0.05) and for continuous heavy lifting (odds ratio 5.7, p = 0.02). The odds ratio for spontaneous abortions was greater among those exposed to four or more solvents (odds ratio 3.5, p=0.05) than among those exposed to one to three solvents (odds ration 0.8, p=0.74).

A study of occupational exposure to antineoplastic drugs and fetal loss in nurses

In a case--control study, we examined the relation between fetal loss and occupational exposure to antineoplastic drugs in nurses in 17 Finnish hospitals. The pregnancies studied occurred in 1973 through 1980 and were identified using three national sources: the Central Register of Health Care Personnel, the Hospital Discharge Registry, and policlinic data. Each nurse with fetal loss was matched with three nurses who gave birth. Data on health and exposure were obtained by self-administered, mailed questionnaires; a response rate of 87 per cent was achieved after three mailings. A statistically significant association was observed between fetal loss and occupational exposure to antineoplastic drugs during the first trimester of pregnancy: odds ratio = 2.30 (95 per cent confidence interval, 1.20 to 4.39). Analyses suggested associations between fetal loss and cyclophosphamide, doxorubicin, and vincristine, although the independent effect of each individual drug could not be specifically identified, since many nurses reported handling more than one of these agents. The results of this study, combined with existing data on animals and human beings, suggest that caution be exercised in the handling of these valuable drugs.

Spermicidal contraceptives and poor reproductive outcomes: the epidemiologic evidence against an association

The first widely publicized report of an association between spermicidal contraception and congenital malformations and spontaneous abortion had considerable impact on obstetric practice. A large number of more recent epidemiologic studies have generally failed to support the earlier finding, and it is concluded that no such association has been demonstrated. The available evidence precludes the need for additional regulation of spermicidal contraception.