Intrapartum Sildenafil in Laboring Mothers

The goal of this feasibility pilot clinical trial is to learn if sildenafil citrate 50mg orally, up to three times during labor, can be appropriately administered, with limited clinical side effects, to laboring mothers to determine feasibility across a spectrum of available healthcare resources. The main questions it aims to answer are: * What are the fetal heart rate monitoring practices in a low-resource setting? * What are the indications for operative delivery in a low-resource? * What is the rate of relevant primary and secondary outcomes to possibly target in a large RCT of intrapartum sildenafil? * What is the limited effect size of sildenafil citrate on maternal and neonatal outcomes in a low-resource setting? Researchers will compare the administration of sildenafil citrate 50 mg orally to a placebo (a look-alike substance that contains no drug) to see if procedures are feasible, the drug is tolerated, the target outcomes are achievable, and effect size is as expected. Participants will: * Take Sildenafil 50 mg/placebo every eight hours or a placebo every eight hours for up to 24 hours during labor * Have the (mothers \& babies) medical charts reviewed for outcomes, including fetal distress, operative delivery, maternal side effects, neonatal bag \& mask ventilation, Apgar scores, and seizures. * Have a neonatal neurological assessment prior to discharge * Have phone call assessments for re-hospitalization or mortality 7 days post-delivery * Receive child development assessments at 1 year, 2 years and 3 years of age by the Ages and Stages Questionnaire administered via a telephone call The results of this feasibility pilot trial will be used to inform the design and conduct of a large pragmatic randomized controlled trial to determine if sildenafil citrate, compared to placebo, will decrease fetal distress and perinatal asphyxia.