Intention to treat: obstetrical management at the threshold of viability.

Background: Despite medical advances in the care of extremely preterm neonates and growing acceptance of resuscitation at 23 and even 22 weeks gestation, controversy remains concerning the use of antepartum obstetric intervention s that are intended to improve outcomes in the setting of anticipated extremely preterm birth. In the absence of demonstrated benefit at <23 weeks gestation and with uncertain benefit at 23 weeks gestation, previous obstetric committee opinions have advised against their use at these gestational ages.

Objective: The purpose of this study was to review the use of obstetric intervention s at the threshold of viability based on neonatal resuscitation plan and to review the odds of survival to neonatal intensive care unit discharge based on use of obstetric intervention s with adjustment for neonatal factors.

Study Design: This retrospective study of 6 study centers reviewed pregnant patients who were admitted between 22+0/7 and 24+6/7 weeks gestation facing delivery from 2011-2015. Patients with known anomalies or missing data were excluded. Records were reviewed for demographics, resuscitation plan, and obstetric intervention s. Mode of delivery, delivery room care, and final infant dispositions were recorded. Multiple gestations were included as 1 pregnancy in regard to the use of obstetric intervention s and were excluded from survival analysis.

Results: Four hundred seventy-eight mothers met the inclusion criteria. When resuscitation was planned, mothers were more likely to receive all conventional obstetric intervention s (antenatal steroids, magnesium sulfate for neuroprotection, tocolytics, and Group Beta Streptococcus prophylaxis), regardless of gestational age at admission, and were more likely to be delivered by cesarean section (P<.05). Analyzed as a group, when antenatal steroids, magnesium sulfate, tocolytics and Group Beta Streptococcus prophylaxis were administered, the odds of survival to neonatal intensive care unit discharge increased for newborn infants who were born at 22 (odds ratio, 11.33; 95% confidence interval, 1.405-91.4) and 23 weeks gestation (odds ratio, 15.5; 95% confidence interval, 3.747-64.11; P<.05). In singletons, the odds of survival to neonatal intensive care unit discharge was not improved by cesarean delivery vs vaginal delivery, even after adjustment for the use of additional interventions, weight, gender, and gestational age (odds ratio, 1.0; 95% confidence interval, 0.59-1.8; P=.912).

Conclusion: In this study, when postnatal resuscitation was planned at 22 and 23 weeks gestation, women were more likely to receive antenatal steroids, magnesium sulfate, and antibiotics; provision of this bundle imparted survival benefit at 23 weeks gestation but could not be demonstrated at 22 weeks gestation because of the small sample size. These findings support of neonate-oriented obstetric interventions in the setting of delivery at 23 weeks gestation when resuscitation is planned and further exploration of optimal obstetric care when resuscitation of infants who were born at 22 weeks gestation is anticipated.