Mode of birth in monochorionic versus dichorionic twin pregnancies: a retrospective study from a large tertiary centre in Germany

Factors influencing sex ratio at birth in Krosno, Poland

The secondary sex ratio (SSR) is a widely used descriptor that reflects the living conditions and health status during pregnancy. The aim of study was to assess the impact of maternal factors, season of birth, and air pollution with the heating season on the sex ratio at birth in the Subcarpathian population from the Krosno district, Poland. A retrospective study involving 11,587 births was occurred at the John Paul II Podkarpackie Province Hospital in Krosno between 2016 and 2020. Sex of the newborn, the season of their birth, as well as the maternal age, birth order, the interval between births, and the season of birth were analysed. Furthermore, the relationship between the SSR and the level of air pollution during the heating season was investigated. To determine the significance of differences in sex ratios, chi-square analysis and multifactorial regression were used, with a significance level set at p < 0.05. At the chi-square level, all the studied factors indicated a statistically significant relationship with the SSR. However, the regression model used shows that maternal age and birth order were the most important factors in shaping the SSR in the study group.

What is the success rate of trial of labor in monochorionic diamniotic twins? A systematic review and meta-analysis of observational studies

OBJECTIVE

This meta-analysis aimed to evaluate the success rate of trial of labor in monochorionic diamniotic pregnancies and the impact of delivery mode on neonatal outcomes.

DATA SOURCES

Searches were performed in MEDLINE/PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and the International Clinical Trials Registry Platform from the inception of each database until April 2022.

STUDY ELIGIBILITY CRITERIA

Selection criteria included observational studies analyzing the delivery mode among monochorionic diamniotic gestations.

METHODS

All analyses were carried out using an intention-to-treat approach, evaluating women according to the delivery mode to which they were assigned in the original studies.

RESULTS

Seventeen studies met the eligibility criteria and were suitable for qualitative and quantitative analysis. In total, 4116 women were analyzed. This meta-analysis showed that trial of labor in monochorionic diamniotic pregnancies resulted in vaginal delivery of both twins in 75.5% of cases (95% confidence interval, 69.1-80.9). Failure to deliver the second twin vaginally occurred in 3.8% of cases (95% confidence interval, 2.5-5.7). In addition, the neonatal outcomes were comparable among women with monochorionic diamniotic pregnancy undergoing different planned delivery modes. Neonatal death occurred in 3.7 per 1000 cases in the planned cesarean delivery group and in 1.6 per 1000 cases in the planned vaginal delivery group. Perinatal death was observed in 7.5 per 1000 cases in the planned cesarean delivery group and in 5.8 per 1000 cases in the planned vaginal delivery group. Umbilical artery pH <7.00 occurred in 0 per 1000 cases in the planned cesarean delivery and 4.6 per 1000 cases in the planned vaginal delivery group. Neonatal intensive care unit stay of >72 hours had a prevalence of 59.7 per 1000 cases in the planned cesarean delivery and 42.8 per 1000 cases in the planned vaginal delivery group.

CONCLUSION

This meta-analysis showed that trial of labor in monochorionic diamniotic pregnancies is successful in most cases and relatively safe, considering that neonatal and perinatal mortality and severe morbidity were comparable between the trial of labor and planned cesarean delivery groups. Therefore, the choice of planned delivery mode in twin gestations should not be made a priori.