Although the onset of spontaneous human parturition has long been known to occur preferentially during the nighttime and early morning hours, no convincing physiological explanation for this pattern has yet been proposed. This review focuses on the circadian timing of mammalian parturition, particularly in the human. It is proposed that differences in the phasing of parturition among different species are likely a function of opposite uterine responses to humoral cues, in particular those coding for time of day. The brain hormone melatonin fulfills many of the prerequisites to serve as a circadian signal for initiating uterine contractions that lead to human parturition. These encompass direct actions of melatonin on myometrial smooth muscle cells that are synergistic with oxytocin in facilitating greater uterine contractions at night. This may not only help to explain the nocturnal phasing of human parturition but also open new avenues for the management of term and preterm labor.
A sexually active, asymptomatic 44-year-old presented for Intrauterine device (IUD) removal that had been in place for 13 years. IUD removal was unsuccessful as the strings could not be located. Imaging revealed an extrauterine IUD and at surgical removal of the abdominal IUD a small bowel perforation requiring bowel resection was required. Uterine perforation is a rare complication of IUD use occurring in approximately 1-1.3 in 1000. Risk factors for perforation include provider inexperience, retroverted uterus, immobile uterus, and myometrial defect from a previous cesarean delivery or myomectomy.
INTRODUCTION:
Our goal was to assess obstetric outcomes and interventions in patients with low normal amniotic fluid index versus oligohydramnios.
METHODS:
This was a retrospective study of deliveries between 2010 and 2014. Oligohydramnios was defined as Amniotic Fluid Index less than 5 cm (AF-5) and low normal amniotic fluid of 5 to 8 cm (AF-LN) on ultrasound performed greater than 24 hours before delivery. Outcomes included cesarean section, preterm delivery, Apgars at 1 and 5 minutes, umbilical artery pH, birth weight (BW), and admission to neonatal intensive care unit (NICU). Statistics included chi-square and student t-test.
RESULTS:
76 cases had AF-5 and 398 had AF-LN. Mean gestational age at delivery was 37.62 and 38.18 weeks (P=.005). Preterm birth rates were higher in AF-5 (P=.003), as well as both primary and all c-section delivery rates (P < .05). Our institution’s overall reported primary cesarean section rate for low risk pregnancies was 24%. Neonatal Apgars and BW were significantly lower in AF-5. There was no significant difference in NICU admissions. One fetal death was observed in each group.
CONCLUSION:
As expected, patients with true oligohydramnios have a higher rate of perinatal morbidity than those with low but normal amniotic fluid, with increased interventions in the true oligohydramnios patients. More investigation is warranted to assess whether earlier intervention in the oligohydramnios group may be the cause of the increased perinatal morbidity.
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