Is vaginal delivery of a fetus in breech presentation at an extremely preterm gestational age associated with an increased risk of neonatal death? A comparative study.

BACKGROUND: The effect on neonatal mortality of mode of delivery of a fetus in breech presentation at an extremely preterm gestational age remains controversial. OBJECTIVE: To compare mortality associated with planned vaginal delivery (PVD) of fetuses in breech presentation with that of fetuses in breech presentation with a planned cesarean delivery (PCD). MATERIAL AND METHODS: Retrospective study reviewing records over a 19-year period in a level 3 university referral center of singleton infants born between 25+0 and 27+6 weeks of gestation, alive on arrival in the delivery room, and weighing at least 500 grams at birth. Infants in the first group were in breech presentation with PVD and the second in breech presentation with PCD. The principal endpoint was neonatal death. RESULTS: During the study period, we observed 113 breech presentations with PVD, and 80 breech presentations with PCD. Although not significant after adjustment, neonatal mortality in the breech PVD group was more than twice that of the breech PCD group (19.5 vs 7.8%, P = 0.031, ORa = 2.6, 95% CI 0.8-9.3, NNT = 8). This higher neonatal mortality in the breech PVD group was exclusively associated with a higher risk of death in the delivery room (12.4 vs 0.0% P = 0.001, OR not calculable, NNT = 8). In these extremely preterm breech presentations with PVD, neonatal mortality in the delivery room was associated with entrapment of the aftercoming head, cord prolapse, and a short duration of labor. CONCLUSION: For deliveries between 25+0 and 27+6 weeks' gestation, vaginal delivery in breech presentation is associated with a higher risk of death in the delivery room.

Effects of adipokines and obesity on uterine contractility.

Obesity is a major public health problem. The prevalence of obesity has significantly increased in developed countries, particularly in France with an overall increase of 76% over the last 15 years. In pregnant women, obesity is associated with alterations in the quality of labor, such as delayed onset of labor, a higher rate of prolonged pregnancies, prolonged labor, and higher oxytocin requirements. There is also an increased prevalence of Cesarean sections, particularly during the active phase of labor, and perinatal complications (postpartum hemorrhage). It seems that some of these functional changes and their consequences can be attributed to a disruption of hormonal balance encountered in obese women and involving adipokines (apelin, ghrelin, visfatin, leptin), but also to the interactions between adipose tissue and the "oxytocin (OT) - oxytocin receptor (OTR)". In this review, we detailed mechanisms to understand the impact of specific metabolic alterations in obesity on uterine contractility. Better knowledge of the impact of obesity on labor and delivery pathophysiology should strengthen the prevention of obesity in women of childbearing age and provide a suitable and effective management. The beneficial effect of weight loss and exercise in non-pregnant women on the correction of metabolic disorders secondary to obesity should be studied in populations of overweight women to demonstrate its effectiveness.