Methamphetamines and Birth Outcomes

Abstract

INTRODUCTION: Methamphetamines are one of the most commonly abused illicit drugs in pregnancy, yet little is known about birth outcomes of exposed neonates. Previous studies were limited because of confounding factors: other drugs of abuse, including tobacco; poverty; poor diet; and lack of prenatal care. This study presents data on birth outcomes controlling these variables. METHODS: Database review study of 261 pregnancies of women obtaining prenatal care from a clinic specializing in the care of women with addictions using prospective data on exposure to methamphetamines and other drugs of abuse, including tobacco. Methamphetamine-exposed pregnancies were compared with nonmethamphetamine-exposed pregnancies. Methamphetamine exposure was documented by either maternal self-report or urine toxicology. RESULTS: One hundred eighteen neonates were exposed to methamphetamine during pregnancy, including 38 first trimester, 38 second trimester, 24 third trimester, and 18 until delivery. There were 90 nonmethamphetamine-exposed neonates. Mean birth weights were the same for methamphetamine-exposed and nonexposed neonates (3,182 compared with 3,193 g, P=.89), although there was a trend for smaller neonates with positive toxicology at birth (2,960 compared with 3,207 g, P=.087). Gestation was nonsignificantly shorter among the methamphetamine-exposed neonates (38.3 compared with 38.7 weeks of gestation, P=.46), and significantly shorter among the neonates with positive toxicology at birth (35.2 compared with 38.7 weeks of gestation, P<.01). CONCLUSIONS: Methamphetamine use is associated with a higher risk of birth before 37 weeks of gestation if used until delivery. Any methamphetamine use did not affect birth weights or gestational ages. Stopping methamphetamine use at any time during pregnancy improves birth outcomes.