To evaluate the incidence of intrauterine fetal growth restriction (IUGR) and small for gestational age (SGA) at birth in women on methadone maintenance therapy who smoke cigarettes compared to those on methadone maintenance therapy who do not smoke cigarettes.METHODS:
A retrospective cohort study of women delivered at Thomas Jefferson University Hospital from 2012 to 2015. We excluded non-singleton pregnancies. We evaluated demographic and obstetric information, ultrasound measurements, including estimated fetal weight (EFW), EFW percentile, head circumference, and abdominal circumference from last ultrasound, as well as delivery and neonatal outcomes, including gestational age at delivery, birth weight (BW), BW percentile, NICU admission, and length of stay in NICU. Smoking history was collected (number of cigarettes, if quit during pregnancy, use per trimester). Primary outcome: incidence of IUGR by last ultrasound and SGA. Secondary outcomes: preterm birth <37 weeks. Adjustment for confounders for fetal growth restriction was performed.RESULTS:
We identified 70 women in the methadone maintenance therapy, 88.5% of whom reported smoking cigarettes and 11.4% of whom did not report smoking. Demographics were not significantly different. The incidence of IUGR and SGA were not significantly different: 4.8% vs 0% P:1.0 and 24.2% vs 25.0% P:1.0, respectively. There were no significant differences in preterm birth, birth weight, NICU admission and length of stay in NICU.CONCLUSION:
In women on methadone maintenance therapy, there is a high incidence of IUGR and SGA; however, IUGR and SGA were not significantly different during pregnancy in women who smoked cigarettes compared to those who did not smoke cigarettes.