Maternal Oxygen Supplementation for Intrauterine Resuscitation

More than 80% of the 3 million women who labor and deliver each year in the United States undergo continuous electronic fetal monitoring (EFM) during labor in order to fetal hypoxia and prevent the transition to acidemia, expedited operative delivery, and/or neonatal morbidity. Category II EFM is the most commonly observed group of fetal heart rate features in labor. One common response to Category II EFM is maternal oxygen (O2) supplementation. The theoretic rationale for O2 administration is that it increases O2 transfer to a hypoxic fetus. There are conflicting national guidelines regarding O2 administration - the American College of Obstetricians and Gynecologists suggest O2 is ineffective, whereas the Association of Women's Health, Obstetric, and Neonatal Nurses recommend continued use given lack of definitive data on safety and efficacy. A recent national survey of nearly 600 Labor