Is induced abortion with misoprostol a risk factor for late abortion or preterm delivery in subsequent pregnancies?

Is a pregnancy following a second trimester uterine evacuation associated with increased adverse maternal and neonatal outcomes?

OBJECTIVE

To evaluate maternal and neonatal outcomes of pregnancies following a uterine evacuation in the second trimester, in comparison to a first trimester spontaneous pregnancy loss.

STUDY DESIGN

A retrospective analysis of data of women who conceived ≤6 months following a uterine evacuation due to a spontaneous pregnancy loss and subsequently delivered in a single tertiary medical center between 2016 and 2021. Maternal and neonatal outcomes were compared between women with second trimester (14-23 weeks) and first trimester (<14 weeks) pregnancy loss. The primary outcome of this study was the preterm delivery (<37 weeks) rate. Secondary outcomes were adverse maternal and neonatal outcomes. Univariate analysis was followed by multiple logistic regression models; adjusted odds ratios (aORs) and 95 % confidence intervals (CIs) were calculated.

RESULTS

During the study period, 1365 women met the inclusion criteria. Of those, 272 (19.9 %) women gave birth following a second trimester uterine evacuation and 1093 (80.1 %) women following a first trimester uterine evacuation. There were no demographic differences between the two groups. No difference was found in the preterm delivery rate in the subsequent pregnancy (5.1 % vs. 5.3 %, p = 0.91), further confirmed in the multivariate analysis [aOR 1.02 (0.53-1.94), p = 0.96]. No differences were identified with respect to other maternal and neonatal parameters examined, including hypertension disorders of pregnancy, third stage placental complications, mode of delivery and neonatal birth weight.

CONCLUSION

Pregnancy conceived shortly after second trimester uterine evacuation as compared to first trimester, confers no additional risk for preterm delivery or other adverse perinatal outcomes. Further studies to strengthen these findings are needed.

The association between maternal anemia during pregnancy and preterm birth

BACKGROUND & AIMS

Maternal anemia is one of the most serious health problems during pregnancy. The causes of anemia include iron deficiency, parasitic diseases, micronutrient deficiencies, and hereditary hemoglobinopathies. Because the reported association between maternal anemia and preterm labor in different studies is varied depending on the month of pregnancy this study aims to determine this relationship after adjustment for potential confounders.

METHODS

A case-control study was conducted among 801 pregnant women (267 cases and 534 controls) in Sardashat, Iran from October 2012 to October 2013. Hemoglobin (Hb) values were measured for all women participating in the study during the first and second trimesters of pregnancy, and the average Hb values were presented. Statistical analyzes were performed with logistic regression.

RESULTS

The mean age of participants was 26.4 ± 5.25 years for the case group and 27.2 ± 6.51 years for the control group. Preterm birth was associated with maternal anemia during pregnancy [aOR = 2.69 (95% CI; 1.46 to 4.95)] even after adjusting for confounding effects including maternal age, history of abortion [aOR = 2.41 (95% CI; 1.42 to 4.08)], history of preterm birth [aOR = 11.38 (95% CI; 3.48 to 37.22)], obesity (aOR: 3.441; CI95%: 1.18-10.06), parity [aOR = 0.42 (95% CI; 0.25 to 0.69)], preeclampsia/eclampsia [aOR = 6.08 (95% CI; 2.64 to 14)], and GDM [aOR = 4.80 (95% CI; 2.02 to 11.41)]).

CONCLUSION

Early detection and adequate treatment of anemia during pregnancy can help reduce the prevalence of preterm birth.

Risk of preterm delivery after medically indicated termination of pregnancy with induced vaginal delivery: a case-control study

We investigated whether nonsurgical termination of pregnancy after 14 weeks of gestation increases the risk of preterm delivery in a subsequent pregnancy. We conducted a two-centre retrospective case-control study. Patients who underwent non-surgical termination of pregnancy after 14 weeks of gestation between 2012 and 2015 and who gave birth after 14 weeks of gestation to a live-born singleton infant were included. Control patients were those who gave birth after 37 weeks of gestation (the same month as a case patient) and had a second delivery of a singleton foetus after 14 weeks of gestation. The primary outcome was preterm delivery during the second pregnancy period. We included 151 cases and 302 controls and observed 13 (8.6%) preterm births during the second pregnancy in the case group versus 8 (2.6%) (odds ratio: 3.62; 95% confidence interval: 1.40-8.65, p < .001) in the control group. This result remained significant after multivariate analysis. Impact statementWhat is already known about this topic? Many studies have evaluated the association between first-trimester surgical or non-surgical termination of pregnancy and the risk of preterm birth in the subsequent pregnancy. However, no study has evaluated the association between second- or third-trimester non-surgical termination of pregnancy due to foetal disease and the risk of preterm birth in the subsequent pregnancy. A small number of studies have included a small proportion of patients who previously underwent non-surgical termination of pregnancy after 14 weeks of gestation and later experienced first-trimester termination during their second pregnancy. These studies focussed on the impact of the interpregnancy interval or pharmacological induction of labour on the risk of preterm delivery in the subsequent pregnancy.What did the results of this study add? This is the first study to specifically evaluate the association between second- and third-trimester non-surgical terminations of pregnancy and the risk of preterm birth in the subsequent pregnancy. When compared with term birth, nonsurgical termination of pregnancy was associated with the risk of spontaneous preterm birth and hospitalisation in the neonatal intensive care unit in the subsequent pregnancy.What are the implications of these findings for clinical practice and further research? Further studies are required to confirm our results, but information delivered to patients with a late termination of pregnancy and during their pregnancy follow-up for the subsequent pregnancy could be modified to provide this information.

Assessing the risk factors before pregnancy of preterm births in Iran: a population-based case-control study

Background

Preterm birth is a major cause of prenatal and postnatal mortality particularly in developing countries. This study investigated the maternal risk factors associated with the risk of preterm birth.

Methods

A population-based case-control study was conducted in several provinces of Iran on 2463 mothers referred to health care centers. Appropriate descriptive and analytical statistical methods were used to evaluate the association between maternal risk factors and the risk of preterm birth. All tests were two-sided, and P values < 0.05 were considered to be statistically significant.

Results

The mean gestational age was 31.5 ± 4.03 vs. 38.8 ± 1.06 weeks in the case and control groups, respectively. Multivariate regression analysis showed a statistically significant association between preterm birth and mother’s age and ethnicity. Women of Balooch ethnicity and age ≥ 35 years were significantly more likely to develop preterm birth (OR: 1.64; 95% CI: 1.01–-2.44 and OR: 9.72; 95% CI: 3.07–30.78, respectively). However, no statistically significant association was observed between preterm birth and mother’s place of residence, level of education, past history of cesarean section, and BMI.

Conclusion

Despite technological advances in the health care system, preterm birth still remains a major concern for health officials. Providing appropriate perinatal health care services as well as raising the awareness of pregnant women, especially for high-risk groups, can reduce the proportion of preventable preterm births.

Shiga Toxin-Producing Escherichia coli Infections during Pregnancy

Gastrointestinal infection with Shiga toxin-producing Escherichia coli (STEC) causes diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS), characterized by hemolytic anemia, thrombocytopenia and acute renal failure. The main virulence factor of STEC is Shiga toxin (Stx), which is responsible for HUS development. STEC can produce Stx type 1 and/or 2 (Stx1, Stx2) and their variants, Stx2 being more frequently associated with severe cases of HUS. This pathology occurs in 5⁻15% of cases with STEC infection when Stx gain access to the bloodstream and causes damage in the target organs such as the kidney and brain. STEC infections affect mainly young children, although the large HUS outbreak with a new Stx2-producing STEC O104:H4 in Europe in 2011 involved more adults than children, and women were over-represented. Maternal infections during pregnancy are associated with adverse pregnancy outcomes. Studies in rats showed that Stx2 binds to the utero-placental unit and causes adverse pregnancy outcomes. In this article, we provide a brief overview of Stx2 action on placental tissues and discuss whether they might cause pregnancy loss or preterm birth.

Prior uterine evacuation of pregnancy as independent risk factor for preterm birth: a systematic review and metaanalysis

BACKGROUND

Preterm birth (PTB) is the number one cause of perinatal mortality. Prior surgery on the cervix is associated with an increased risk of PTB. History of uterine evacuation, by either induced termination of pregnancy (I-TOP) or spontaneous abortion (SAB), which involve mechanical and/or osmotic dilatation of the cervix, has been associated with an increased risk of PTB in some studies but not in others.

OBJECTIVE

The objective of the study was to evaluate the risk of PTB among women with a history of uterine evacuation for I-TOP or SAB.

DATA SOURCES

Electronic databases (MEDLINE, Scopus, ClinicalTrials.gov, EMBASE, and Sciencedirect) were searched from their inception until January 2015 with no limit for language.

STUDY ELIGIBILITY CRITERIA

We included all studies of women with prior uterine evacuation for either I-TOP or SAB, compared with a control group without a history of uterine evacuation, which reported data about the subsequent pregnancy.

STUDY APPRAISAL AND SYNTHESIS METHODS

The primary outcome was the incidence of PTB < 37 weeks. Secondary outcomes were incidence of low birthweight (LBW) and small for gestational age (SGA). We planned to assess the primary and the secondary outcomes in the overall population as well as in studies on I-TOP and SAB separately. The pooled results were reported as odds ratio (OR) with 95% confidence interval (CI).

RESULTS

We included 36 studies in this metaanalysis (1,047,683 women). Thirty-one studies reported data about prior uterine evacuation for I-TOP, whereas 5 studies reported data for SAB. In the overall population, women with a history of uterine evacuation for either I-TOP or SAB had a significantly higher risk of PTB (5.7% vs 5.0%; OR, 1.44, 95% CI, 1.09-1.90), LBW (7.3% vs 5.9%; OR, 1.41, 95% CI, 1.22-1.62), and SGA (10.2% vs 9.0%; OR, 1.19, 95% CI, 1.01-1.42) compared with controls. Of the 31 studies on I-TOP, 28 included 913,297 women with a history of surgical I-TOP, whereas 3 included 10,253 women with a prior medical I-TOP. Women with a prior surgical I-TOP had a significantly higher risk of PTB (5.4% vs 4.4%; OR, 1.52, 95% CI, 1.08-2.16), LBW (7.3% vs 5.9%; OR, 1.41, 95% CI, 1.22-1.62), and SGA (10.2% vs 9.0%; OR, 1.19, 95% CI, 1.01-1.42) compared with controls. Women with a prior medical I-TOP had a similar risk of PTB compared with those who did not have a history of I-TOP (28.2% vs 29.5%; OR, 1.50, 95% CI, 1.00-2.25). Five studies, including 124,133 women, reported data about a subsequent pregnancy in women with a prior SAB. In all of the included studies, the SAB was surgically managed. Women with a prior surgical SAB had a higher risk of PTB compared with those who did not have a history of SAB (9.4% vs 8.6%; OR, 1.19, 95% CI, 1.03-1.37).

CONCLUSION

Prior surgical uterine evacuation for either I-TOP or SAB is an independent risk factor for PTB. These data warrant caution in the use of surgical uterine evacuation and should encourage safer surgical techniques as well as medical methods.

Second trimester dilation and evacuation: a risk factor for preterm birth?

OBJECTIVE

To evaluate whether second trimester pregnancy termination with dilation and evacuation (D&E) vs induction of labor (IOL) affects subsequent risk of preterm birth.

STUDY DESIGN

Our cohort was a retrospective cohort of women undergoing second trimester pregnancy termination for fetal anomalies, fetal death or previable premature rupture of membranes. We analyzed the rates of spontaneous delivery <37 weeks in the first pregnancy following the termination. We also compared preterm birth rates in our cohort with national averages and analyzed by the total number of prior procedures.

RESULT

There were 173 women in our cohort. Women who had undergone a D&E (n=130) were less likely to have a subsequent preterm birth (6.9 vs 30.2%; P<0.01). This held true for a low risk subset without obstetric risk factors. There was no statistical difference in preterm birth rates for women who had undergone a D&E as compared with national averages, nor between the rates of preterm birth for women with 0, 1, 2 or 3 or more prior first or second trimester procedures.

CONCLUSION

We did not find that D&E was a risk factor for preterm delivery when compared with women with a prior IOL or national rates.

The postnatal morbidity associated with second-trimester miscarriage

OBJECTIVE(S)

To describe the complications, and their incidence, associated with the management and delivery of a distinct second-trimester miscarriage cohort.

METHODS

A retrospective cohort study was undertaken in a large, tertiary-referral university hospital (8500 deliveries per annum). All cases of pregnancy loss occurring between 14(+0) and 23(+6) were identified from July 2009 to June 2013 (n = 181). Medical notes were reviewed and the number of complications among this cohort was identified. Logistic regression was conducted to assess associations with clinical presentation and management.

RESULTS

The mean gestation of loss was 18(+2) weeks (SD: 2(+2)). 64.6% (n = 117) of the total losses were of intrauterine fetal demise (IUFD) with 17.7% (n = 32) following preterm premature rupture of membranes (PPROM) and 17.7% (n = 32) following preterm labour (PTL). All women required inpatient admission with 59.1% (n = 107) undergoing medical induction of labour. PPROM cases, compared with cases of IUFD, had increased odds of requiring antibiotic therapy (OR 13.75, 95% CI: 4.88-38.72) and readmission (OR OR 4.15, 95% CI 1.12-15.36).

CONCLUSION

These women represent a small proportion of the obstetric population but remain a distinct cohort whose management is complicated by high rates of morbidity requiring medical intervention. An awareness of these risks should inform future clinical practice.

Evidence of an immunosuppressive effect of progesterone upon in vitro secretion of proinflammatory and prodegradative factors in a model of choriodecidual infection

OBJECTIVE

To evaluate whether progesterone (P4) is able to modulate the secretion of tumour necrosis factor α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8, IL-10 and matrix metalloproteinase-9 (MMP-9) after choriodecidual stimulation with lipopolysaccharide (LPS).

DESIGN

Chorioamnionitis-elicited preterm delivery is associated with an uncontrolled secretion of proinflammatory cytokines that may induce MMPs, which modify the fine immunological and structural equilibrium at the fetal-maternal interface.

SETTING

Instituto Nacional de Perinatología 'Isidro Espinosa de los Reyes', Mexico City.

SAMPLE

Twelve human fetal membranes at term from healthy patients were placed in a two-chamber culture system.

METHODS

Choriodecidual and amniotic regions were preincubated with 1.0, 0.1, or 0.01 μmol/l P4 for 24 hours; after which the choriodecidual region was costimulated with 1000 ng/ml of LPS for 24 hours.

MAIN OUTCOME MEASURES

Descriptive statistics were obtained for each variable. Data distribution was tested for normality using Kolmogorov-Smirnoff and Shapiro-Wilk tests. When distribution was normal, Student's t test was used to analyse for differences among groups. Mann-Whitney's U test was used when data were not normally distributed.

RESULTS

Pretreatment with 1.0 μmol/l P4 significantly blunted the secretion of TNF-α, IL-1β, IL-6, IL-8 and IL-10. MMP-9 was inhibited with 0.1 μmol/l P4. Mifepristone (RU486) blocked the immunosuppressive effect of P4, suggesting a P4 effect mediated by its receptor.

CONCLUSION

These results offer evidence to support the concept that P4 can protect the fetal-placental unit through a compensatory mechanism that partially limits the secretion of proinflammatory and prodegradative modulators.

Term induction of labor and subsequent preterm birth

OBJECTIVE

Although the rate of inductions continues to rise, there is a paucity of data investigating subsequent pregnancy outcomes after induction. Our objective was to compare term inductions with term spontaneous labor and evaluate the rate of subsequent spontaneous preterm birth (sPTB).

STUDY DESIGN

A retrospective cohort study of women with 2 consecutive deliveries from 2005 through 2010 was performed. Term inductions or term spontaneous labor in the index pregnancy was included, and those with a prior sPTB were excluded. Data were obtained through chart abstraction. The primary outcome was sPTB (<37 weeks) in a subsequent pregnancy. Categorical variables were compared with χ(2) analyses, and logistic regression was used to calculate odds.

RESULTS

Eight hundred eighty-seven women were included (622 inductions, 265 spontaneous labor). The overall subsequent sPTB rate was 7.2%. Term inductions were less likely to have a subsequent sPTB compared with term spontaneous labor (6% vs 11%; odds ratio [OR], 0.49; 95% confidence interval, 0.29-0.81; P = .005). This remained after adjusting for confounders (adjusted OR, 0.55; P = .04). The sPTB risk depended on gestational age of index delivery. At 37-38.9 weeks, the sPTB rate after spontaneous labor was 24% vs 9% after induction (OR, 3.0; 95% confidence interval, 1.44-6.16; P = .003). This was not significant for 39-39.9 weeks (P = .2) or 40 weeks or longer (P = .8).

CONCLUSION

Induction is not a risk factor for subsequent sPTB. Spontaneous labor, however, in the early term period is associated with subsequent sPTB. Further investigation among early term deliveries is warranted to evaluate the risk of sPTB and target interventions in this cohort.

Prolonged endoplasmic reticulum stress alters placental morphology and causes low birth weight

The role of endoplasmic reticulum (ER) stress in pregnancy remains largely unknown. Pregnant mice were subcutaneously administered tunicamycin (Tun), an ER stressor, as a single dose [0, 50, and 100 μg Tun/kg/body weight (BW)] on gestation days (GDs) 8.5, 12.5, and 15.5. A high incidence (75%) of preterm delivery was observed only in the group treated with Tun 100 μg/kg BW at GD 15.5, indicating that pregnant mice during late gestation are more susceptible to ER stress on preterm delivery. We further examined whether prolonged in utero exposure to ER stress affects fetal development. Pregnant mice were subcutaneously administered a dose of 0, 20, 40, and 60 μg Tun/kg from GD 12.5 to 16.5. Tun treatment decreased the placental and fetal weights in a dose-dependent manner. Histological evaluation showed the formation of a cluster of spongiotrophoblast cells in the labyrinth zone of the placenta of Tun-treated mice. The glycogen content of the fetal liver and placenta from Tun-treated mice was lower than that from control mice. Tun treatment decreased mRNA expression of Slc2a1/glucose transporter 1 (GLUT1), which is a major transporter for glucose, but increased placental mRNA levels of Slc2a3/GLUT3. Moreover, maternal exposure to Tun resulted in a decrease in vascular endothelial growth factor receptor-1 (VEGFR-1), VEGFR-2, and placental growth factor. These results suggest that excessive and exogenous ER stress may induce functional abnormalities in the placenta, at least in part, with altered GLUT and vascular-related gene expression, resulting in low infant birth weight.

Progesterone reverts LPS-reduced FAAH activity in murine peripheral blood mononuclear cells by a receptor-mediated fashion

Increased anandamide concentrations are associated with pregnancy failure. Anandamide levels are regulated by the fatty acid amide hydrolase (FAAH). The aim of the study was to investigate the role of progesterone (P) on FAAH modulation in murine peripheral blood mononuclear cells (PBMC) under septic conditions. We observed that in vivo administration of LPS to non-pregnant (NP) mice decreased FAAH activity of PBMC while in pregnant mice no changes in FAAH activity were observed. NP animals administered with P had a similar response to LPS as the pregnant animals. Also, NP mice injected with P antagonist and P showed that the effect of P on LPS-reduced FAAH activity was impaired. Furthermore, LPS produced a decrease in the ratio of PR-B/PR-A in NP animals. Our results showed that, in our model the endotoxin decreased PBMC's FAAH activity and this condition was reverted by P in a receptor-mediated fashion.

Progesterone is essential for protecting against LPS-induced pregnancy loss. LIF as a potential mediator of the anti-inflammatory effect of progesterone

Lipopolysaccharide (LPS) administration to mice on day 7 of gestation led to 100% embryonic resorption after 24 h. In this model, nitric oxide is fundamental for the resorption process. Progesterone may be responsible, at least in part, for a Th2 switch in the feto-maternal interface, inducing active immune tolerance against fetal antigens. Th2 cells promote the development of T cells, producing leukemia inhibitory factor (LIF), which seems to be important due to its immunomodulatory action during early pregnancy. Our aim was to evaluate the involvement of progesterone in the mechanism of LPS-induced embryonic resorption, and whether LIF can mediate hormonal action. Using in vivo and in vitro models, we provide evidence that circulating progesterone is an important component of the process by which infection causes embryonic resorption in mice. Also, LIF seems to be a mediator of the progesterone effect under inflammatory conditions. We found that serum progesterone fell to very low levels after 24 h of LPS exposure. Moreover, progesterone supplementation prevented embryonic resorption and LPS-induced increase of uterine nitric oxide levels in vivo. Results show that LPS diminished the expression of the nuclear progesterone receptor in the uterus after 6 and 12 h of treatment. We investigated the expression of LIF in uterine tissue from pregnant mice and found that progesterone up-regulates LIF mRNA expression in vitro. We observed that LIF was able to modulate the levels of nitric oxide induced by LPS in vitro, suggesting that it could be a potential mediator of the inflammatory action of progesterone. Our observations support the view that progesterone plays a critical role in a successful pregnancy as an anti-inflammatory agent, and that it could have possible therapeutic applications in the prevention of early reproductive failure associated with inflammatory disorders.

The use of misoprostol in termination of second-trimester pregnancy

Misoprostol, a synthetic prostaglandin E1 analog, is initially used to prevent peptic ulcer. The initial US Food and Drug Administration-approved indication in the product labeling is the treatment and prevention of intestinal ulcer disease resulting from nonsteroidal anti-inflammatory drugs use. In recent two decades, misoprostol has approved to be an effective agent for termination of pregnancy in various gestation, cervical ripening, labor induction in term pregnancy, and possible management of postpartum hemorrhage. For the termination of second-trimester pregnancy using the combination of mifepristone and misoprostol seems to have the highest efficacy and the shortest time interval of abortion. When mifepristone is not available, misoprostol alone is a good alternative. Misoprostol, 400 μg given vaginally every 3-6 hours, is probably the optimal regimen for second-trimester abortion. More than 800 μg of misoprostol is likely to have more side effects, especially diarrhea. Although misoprostol can be used in women with scarred uterus for termination of second-trimester pregnancy, it is recommended that women with a scarred uterus should receive lower doses and do not double the dose if there is no initial response. It is also important for us to recognize the associated teratogenic effects of misoprostol and thorough consultation before prescribing this medication to patients regarding these risks, especially when failure of abortion occurs, is needed.

Reproductive outcomes following induced abortion: a national register-based cohort study in Scotland

OBJECTIVE

To investigate reproductive outcomes in women following induced abortion (IA).

DESIGN

Retrospective cohort study.

SETTING

Hospital admissions between 1981 and 2007 in Scotland.

PARTICIPANTS

Data were extracted on all women who had an IA, a miscarriage or a live birth from the Scottish Morbidity Records. A total of 120 033, 457 477 and 47 355 women with a documented second pregnancy following an IA, live birth and miscarriage, respectively, were identified.

OUTCOMES

Obstetric and perinatal outcomes, especially preterm delivery in a second ongoing pregnancy following an IA, were compared with those in primigravidae, as well as those who had a miscarriage or live birth in their first pregnancy. Outcomes after surgical and medical termination as well as after one or more consecutive IAs were compared.

RESULTS

IA in a first pregnancy increased the risk of spontaneous preterm birth compared with that in primigravidae (adjusted RR (adj. RR) 1.37, 95% CI 1.32 to 1.42) or women with an initial live birth (adj. RR 1.66, 95% CI 1.58 to 1.74) but not in comparison with women with a previous miscarriage (adj. RR 0.85, 95% CI 0.79 to 0.91). Surgical abortion increased the risk of spontaneous preterm birth compared with medical abortion (adj. RR 1.25, 95% CI 1.07 to 1.45). The adjusted RRs (95% CI) for spontaneous preterm delivery following two, three and four consecutive IAs were 0.94 (0.81 to 1.10), 1.06 (0.76 to 1.47) and 0.92 (0.53 to 1.61), respectively.

CONCLUSIONS

The risk of preterm birth after IA is lower than that after miscarriage but higher than that in a first pregnancy or after a previous live birth. This risk is not increased further in women who undergo two or more consecutive IAs. Surgical abortion appears to be associated with an increased risk of spontaneous preterm birth in comparison with medical termination of pregnancy. Medical termination was not associated with an increased risk of preterm delivery compared to primigravidae.