Cervical ripening and induction of labor by prostaglandin E2: a comparison between intracervical gel and vaginal pessary.

OBJECTIVE: To compare the effectiveness and safety of two formulations of prostaglandin (PG) E2 (gel and pessary) for induction of labor. Primary outcomes were cervical ripening, initiation/duration of labor, and type of delivery. STUDY DESIGN: A total of 115 women with singleton gestations were consecutively enrolled and assigned to receive intracervical PGE2 (dinoprostone 0.5 mg) by gel (n = 66) or PGE2 (dinoprostone 10 mg) by intravaginal pessary (n = 49). RESULTS: Independently from parity, the vaginal pessary induced successful cervical ripening with a slightly higher but not statistically significant occurrence of vaginal delivery with respect to gel induction. The mean time interval from induction to vaginal delivery did not differ between groups, despite being shorter for the pessary group in inducation-delivery intervals > 12 h. No significant differences were found between the groups with respect to patients who required a second course of PGE2 (9% vs. 2%), as well as oxytocin (11% vs. 13%) induction. No significant difference was found in the incidence of uterine hyperstimulation and other adverse reactions in nulliparas, or in fetal and neonatal outcome. CONCLUSION: Independently from parity, both PGE2 administration routes appeared to be effective in achieving cervical ripening, initiation of labor and optimal type of delivery, and showed the same incidence of side-effects.

Abnormal umbilical artery Doppler waveforms and cord blood inhibin a and inhibin B levels.

Inhibin A and inhibin B are glycoprotein hormones produced by human placenta and by several fetal organs during pregnancy. They are secreted in maternal circulation in increasing amounts from early until term pregnancy, and in umbilical cord blood levels are significantly lower than in maternal serum and do not differ from mid-pregnancy to term gestation. In the present study, we aimed to determine whether secretion of inhibin A and inhibin B into the fetal circulation is increased in pregnancies complicated by umbilical-placental vascular insufficiency. A group of women (n = 13) with abnormal Doppler umbilical artery flow velocimetry and a group of control women (n = 11) with uncomplicated term pregnancies and normal umbilical artery flow velocity waveforms were studied. In each woman, inhibin A and inhibin B concentrations were estimated in umbilical cord artery and vein. In the two groups of women, mean inhibin A levels did not differ between umbilical cord artery and vein. In addition, no difference was retrieved both in umbilical cord artery and vein values between healthy controls and patients with abnormal Doppler umbilical artery flow velocimetry. On the contrary, inhibin B levels were significantly higher in samples from umbilical cord vein than artery, in both groups of pregnant women (both p < 0.001). However, women with abnormal Doppler umbilical artery flow velocimetry had inhibin B levels significantly higher than healthy controls (p = 0.005) only in the umbilical cord artery, but not in the vein. In the presence of abnormal Doppler umbilical artery flow velocity, the concentrations of inhibin B are increased in the arterial umbilical circulation, suggesting that inhibin B is released from multiple fetal sources as a response to hypoxemic stress. As inhibins may affect the hypothalamus-pituitary-adrenal axis which plays an important role in the mechanisms of adaptations to the post-natal life, inhibin B in fetal circulation might then be beneficial to a fetus whose intrauterine survival is threatened by impaired umbilical-placental blood flow.

Inhibin A, inhibin B and activin A concentrations in umbilical cord artery and vein.

Activin A and inhibins (A and B) are growth factors expressed during pregnancy by the human placenta, decidua and fetal membranes, and by several fetal organs. They are secreted in both the maternal and the fetal circulations, but the net contribution of the fetus to inhibins/activin A production is still unclear. In the present study we determined whether there was a difference in the serum concentration of activin A, inhibin A and inhibin B between the artery and vein of the umbilical cord. Arterial and venous umbilical cord blood was obtained immediately before elective Cesarean section of 16 term infants from uncomplicated pregnancies. Inhibins and activin A levels were assayed by specific enzyme-linked immunosorbent assays. The paired t-test and linear regression analysis were used to calculate statistical significance. Inhibin A levels did not differ between the artery and vein of the umbilical cord. In contrast, arterial inhibin B levels were significantly (p < 0.001) lower, and activin A concentrations significantly (p < 0.05) higher than the respective venous concentrations. A significant correlation between arterial and venous levels of inhibin A (r = 0.591; p < 0.05), inhibin B (r = 0.749; p < 0.0001) and activin A (r = 0.571; p < 0.05) was found. The present findings suggest that the human placenta is the main source of inhibin B, and the fetus of activin A, in the umbilical cord. In light of the possible roles played by inhibin and activin in erythroid differentiation, protection of neurons against brain injury and modulation of adrenal and pancreatic hormone release, the present data may be of help in evaluating their changes in the umbilical cord when gestational diseases occur.