Intrapartum Sildenafil to Improve Perinatal Outcomes: A Randomized Clinical Trial.

Area of Science:

• Obstetrics and Gynecology
• Neonatal Medicine
• Pharmacology

Background:

• Sildenafil citrate's potential to increase uteroplacental blood flow suggests a possible benefit in reducing perinatal complications.
• However, its effectiveness in mitigating adverse outcomes linked to intrapartum fetal hypoxia remains uncertain.

Purpose of the Study:

• To evaluate the efficacy of intrapartum maternal oral sildenafil citrate compared to placebo in enhancing perinatal outcomes potentially associated with intrapartum hypoxia in term pregnancies.

Main Methods:

• A pragmatic, multicenter, randomized clinical trial involving 3257 women across 13 Australian hospitals.
• Participants received either 50 mg oral sildenafil citrate every 8 hours or an equivalent placebo.
• The primary composite outcome included stillbirth, neonatal death, severe neonatal depression, acidosis, hypoxic ischemic encephalopathy, and other serious neonatal morbidities.

Main Results:

• The primary composite outcome occurred in 5.1% of the sildenafil group and 5.2% of the placebo group (RR, 1.02; 95% CI, 0.75-1.37), showing no significant difference.
• Sildenafil citrate did not significantly affect rates of emergency cesarean delivery or instrumental birth for fetal distress.
• No significant effect was observed on any individual component of the primary composite outcome, with no evidence of treatment effect heterogeneity in subgroup analyses.

Conclusions:

• Intrapartum maternal oral sildenafil citrate administration did not lead to a reduced incidence of adverse perinatal outcomes linked to intrapartum hypoxia.
• The findings do not support the use of sildenafil citrate for improving perinatal outcomes in term pregnancies experiencing or at risk of intrapartum hypoxia.