Association between progesterone treatment and neonatal outcome in preterm births: a retrospective analysis.

This retrospective study was conducted to determine if infants born prematurely despite prophylactic maternal progesterone treatment during pregnancy may still benefit from its adjunct properties and have decreased neonatal complications. 248 women treated with vaginal/intramuscular progesterone during pregnancy and 2519 controls who gave birth to a preterm newborn (24 + 0-36 + 6 gestational weeks) at a tertiary medical centre in 2012-2019. The primary outcome measure was neonatal infectious composite outcome. Secondary outcome measures were other maternal and neonatal complications. Compared to controls, the study group was characterised by lower gestational age at birth (35.0 ± 2.66 vs. 36.0 ± 2.23 weeks, p < .001), lower birth weight (2294 vs. 2485 g, p < .001), higher rates of neonatal infectious composite outcome (27.82 vs. 21.36%, p = 0.024), NICU admission, periventricular leukomalacia, and mechanical ventilation. The higher neonatal infectious composite outcome is likely associated with the lower gestational age at birth in this high-risk group and not the progesterone treatment per se.IMPACT STATEMENTWhat is already known on this subject? Several randomised controlled trials have shown that progesterone administration in pregnancy significantly reduced the rate and complications of preterm birth. A recent study reported that vaginal administration of progesterone during pregnancy was more effective than intramuscular administration in decreasing vaginal group B Streptococcus (GBS) colonisation. This finding raises the question of whether progesterone treatment may have additional benefits besides preventing preterm birth and may reduce neonatal complication rate in preterm infants.What do the results of this study add? This is the first study examining the impact of gestational progesterone exposure on outcomes of preterm infants. The primary objective was a composite measure of infectious neonatal outcomes. Newborns who had progesterone exposure on average had lower gestational age, lower birth weight and higher neonatal infectious composite outcome. The significant difference is explained by lower gestational age.What are the implications of these findings for clinical practice and/or further research? Progesterone is widely used to prevent preterm birth, and may have important additive effects even when prematurity is not avoided. Although the findings did not support our initial hypothesis, they warrant further examination with larger cohorts.

Fetal reduction from twin to singleton gestation: A meta-analysis.

OBJECTIVE: To evaluate outcomes of fetal reduction in twin pregnancy. SEARCH STRATEGY: PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and Google Scholar were searched from 1980 through December 2020. SELECTION CRITERIA: Prospective or retrospective studies of pregnant women with twin gestations who had a transabdominal reduction of twin to singleton pregnancy with a comparison group of ongoing twin gestations. DATA COLLECTION AND ANALYSIS: Outcomes were meta-analyzed only if reported in at least three studies. MAIN RESULTS: Six studies with a pooled sample of 2867 women with a twin pregnancy of whom 624 underwent 2-to-1 reduction and 2243 did not. In the fetal reduction group, the odds of preterm birth before 34 and 37 weeks of pregnancy were lower by 36% (odds ratio [OR] 0.64, 95% confidence interval [CI] 0.48-0.86, P < 0.003) and 77% (OR 0.23, 95% CI 0.12-0.44, P < 0.001), respectively, than in the control group, and the odds of hypertensive disorders and cesarean delivery were lower by 75% (OR 0.25, 95% CI 0.15-0.43, P < 0.001) and 65% (OR 0.35, 95% CI 0.20-0.62, P < 0.001), respectively. CONCLUSION: Twin reduction to singleton pregnancy decreased the possibility of preterm birth, hypertensive disorders in pregnancy and cesarean delivery. Sufficiently powered prospective studies are needed to support these findings.

Pregnancy outcome following fetal reduction from dichorionic twins to singleton gestation.

BACKGROUND: There are still some controversies regarding the risks and benefits of fetal reduction from twins to singletons. We aimed to evaluate if fetal reduction from twins to singleton improves pregnancy outcome. METHODS: Retrospective analysis of all dichorionic-diamniotic twin pregnancies, who underwent fetal reduction. Pregnancy outcome was compared to ongoing, non-reduced, dichorionic-diamniotic gestations. Primary outcome was preterm birth prior to 37 gestational weeks. Secondary outcomes included: preterm birth prior to 34 gestational weeks, gestational age at delivery, birthweight, small for gestational age, hypertensive disorders, gestational diabetes and stillbirth. RESULTS: Ninety-eight reduced pregnancies were compared with 222 ongoing twins. Preterm birth < 37 gestational weeks (39.6% vs. 57.6%, p < 0.001) was significantly lower in the reduced group compared to the ongoing twins' group. A multivariate analysis, controlling for parity and mode of conception, demonstrated that fetal reduction independently and significantly reduced the risk for prematurity (aOR 0.495, 95% CI -0.299-0.819). Subgroup analysis, similarly adjusted demonstrated lower rates of preterm delivery in those undergoing elective reduction (aOR = 0.206, 95% CI 0.065-0.651), reduction due to fetal anomalies (aOR = 0.522, 95% CI 0.295-0.926) and 1st trimester reduction (aOR = 0.297, 95% Cl 0.131-0.674) all compared to ongoing twins. A Kaplan-Meier survival curve showed a significant proportion of non-delivered women at each gestational week in the reduced group compared to non-reduced twins, after 29 gestational weeks. CONCLUSIONS: Fetal reduction from twins to singleton reduces the risk of preterm birth < 37 gestational weeks, but not for more severe maternal and perinatal complications.