Indocin use in pregnancy: neonatal outcomes.

INTRODUCTION: The objective of this study was to prove that the chronic use of indomethacin as a tocolytic agent does not affect neonatal outcomes.

METHODS: This is a retrospective cohort study of obstetrical patients from All Children's Perinatology Group diagnosed with preterm labor, cervical insufficiency, or both and exposed to prolonged indomethacin therapy (more than 48 hours). Patients were given a loading dose of 50 mg every 6 hours for 48 hours followed by a maintenance dose of 50 mg twice a day. The study period was from December 2010 to December 2012. Data collected included maternal demographics, newborn characteristics, and composite neonatal morbidity (intraventricular hemorrhage, respiratory distress syndrome, sepsis, anemia, retinopathy of prematurity, patent ductus arteriosus). Statistical analysis including power and logistic regression were performed using SAS Enterprise Guide 4.3 and G*Power 3.1.7.

RESULTS: Among 23 patients meeting inclusion criteria, 19 were admitted to the neonatal intensive care unit. After controlling for gestational age at the time of delivery and duration of therapy, we found that longer duration was associated with increased gestational age. During statistical analysis, respiratory distress syndrome on admission was found to be significantly associated with shorter duration of therapy. This association was confounded by gestational age. After performing a power analysis, we found that a much larger sample (2,000+) is needed to find a difference in outcomes.

CONCLUSION: In our cohort, duration of indomethacin therapy does not affect the association between prematurity and composite neonatal morbidity. However, further research with a larger sample is needed to see a statistical difference in composite neonatal outcomes and duration of therapy.