Prophylactic oral nifedipine to reduce preterm delivery: a randomized controlled trial in women at high risk.

OBJECTIVE: To establish the efficacy of prophylactic nifedipine vs. placebo in reducing spontaneous preterm delivery in asymptomatic women at high risk for preterm delivery. DESIGN: Prospective multicentric randomized double-blind study. SETTING: Tertiary care centre, University Hospitals of Brescia and Torino, Italy. POPULATION: Eighty-seven singleton pregnancies without uterine contractions and ultrasonographic cervical length of ≤25 mm at 24-32 weeks, at risk for preterm delivery, with longitudinal follow up in our Preterm Prevention Clinic. METHODS: Selection was done on the basis of ultrasonographic cervical length; 43 women were randomized to receive placebo and 44 to receive nifedipine. MAIN OUTCOME MEASURES: Primary end point: spontaneous preterm delivery <37 weeks in nifedipine vs. placebo. SECONDARY OUTCOMES: delivery <32 weeks, maternal side effects, neonatal complications, admissions to the Neonatal Intensive Care Unit and randomization/delivery time in nifedipine vs. placebo. RESULTS: There was no trend towards a lower risk of spontaneous preterm delivery, neither at <37 weeks of nifedipine vs. placebo (11.4% vs. 19.0%; p = 0.320), or <32 weeks (2.3% vs. 2.4%; p = 0.973). Nifedipine reduced spontaneous preterm delivery <37 weeks (p = 0.015) in the multiparous women by stratified analysis for parity. SECONDARY OUTCOMES between the groups did not differ except for a higher percentage of maternal side-effects in the nifedipine group (31.8%) vs. placebo (11.9%) (p < 0.05). Subgroup analysis showed a borderline (p = 0.047) lower percentage of spontaneous preterm delivery in women with a ultrasonographic cervical length of <20 mm in the nifedipine group. CONCLUSIONS: Prophylactic nifedipine in asymptomatic women at high risk for preterm delivery had a positive effect on the rate of spontaneous preterm delivery <37 weeks in multiparous women.

Placental histology in clinically unexpected severe fetal acidemia at term.

BACKGROUND: Fetal acidemia at birth is defined as a newborn condition wherein the cord blood pH value is less than 7.0. It could represent an association with newborn brain damage; therefore, it is important to investigate which conditions precipitate its occurrence. No extensive placental analysis has been performed in cases of acidotic newborns delivered from low-risk pregnancies. AIMS: To study placental characteristics in cases with severe fetal acidemia. STUDY DESIGN: Retrospective case-control study. SUBJECT: 34 cases, 102 controls. OUTCOME MEASURES: Umbilical artery pH was measured at delivery from a doubly clamped portion of the cord. Placental characteristics were compared between cases with severe fetal acidemia (cord pH at birth <7.0) and controls (normal pH at birth) in term low-risk pregnancies. RESULTS: Macroscopic placental and umbilical cord characteristics were comparable in cases and controls whereas histological characteristics exhibited differences: diffuse villous edema, increased number of syncytial knots and villous branching abnormalities significantly affected cases more frequently than controls. Diffuse villous edema is related to fetal vascularization and associated with an increase of venous pressure; in our low-risk population, it is conceivable that these changes of fetal flow and pressure occurred in labor during the alteration of fetal heart rate. An increased number of syncytial knots and villous branching abnormalities have been previously associated with chronic placental hypoxic condition; in our low-risk population they could reflect a clinically undetectable hypoxic situation that acted during pregnancy reducing fetal resources to bear labor and delivery. CONCLUSIONS: Placental histology provides useful information related to fetal acidemia in low-risk term pregnancy.

The combination of short cervical length and phIGFBP-1 in the prediction of preterm delivery in symptomatic women.

OBJECTIVE: To assess the combined use of cervical length and cervical phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1) in the prediction of preterm delivery in symptomatic women. METHODS: Cervical length was prospectively measured in 102 consecutive singleton pregnancies with intact membranes and regular contractions at 24-32 weeks, and phIGFBP-1 was assessed in those with a cervix ≤30 mm. RESULTS: Among women with a cervix >30 mm (n = 42), none delivered <34 weeks or within 7 days. Among women with a cervical length ≤30 mm (n = 60), eight delivered <34 weeks, four of which within 7 days. A positive phIGFBP-1 conferred a significantly increased risk of delivery before 34 weeks in women with a cervix ≤30 mm (likelihood ratio 2.32, 95% confidence interval 1.15-4.67), and a significantly increased risk of delivering within 7 days in the subgroup of women with a cervical length of 20-30 mm (likelihood ratio 3.64, 95% confidence interval 2.20-6.01). CONCLUSIONS: In symptomatic women with a cervical length >30 mm the risk of preterm delivery is very low. In women with a cervix ≤30 mm, adding phIGFBP-1 assessment may improve the risk assessment for preterm delivery, and help to plan subsequent pregnancy management.