Neurobehavioral outcomes of infants exposed to MDMA (Ecstasy) and other recreational drugs during pregnancy

MDMA (Ecstasy) use during pregnancy is linked to poorer motor quality and lower milestone attainment in infants at 4 months, with a dose-response relationship: greater exposure corresponds to worse motor outcomes. This first prospective study of prenatal MDMA exposure in humans compared 28 women who used MDMA during pregnancy with 68 polydrug-using women who did not, controlling for confounding factors. MDMA-using mothers had fewer prior births and more health, work, and social problems. Exposed infants were more likely to be male. The findings suggest risk to the developing infant and indicate that continued follow-up is needed to determine whether early motor delays persist or resolve.

Study at a glance

Abstract

3,4-methylenedioxymethamphetamine (MDMA) or "Ecstasy" is one of the most widely used illicit recreational drugs among young adults. MDMA is an indirect monoaminergic agonist and reuptake inhibitor that primarily affects the serotonin system. Preclinical studies in animals have found prenatal exposure related to neonatal tremors and long-term learning and memory impairments. To date, there are no prospective studies of the sequelae of prenatal exposure to MDMA in humans, despite concerns about its potential for harmful effects to the fetus. The present study is the first to prospectively identify MDMA-using women during pregnancy and to document patterns and correlates of use with neonatal and early infancy outcomes of offspring. All mothers and infants were prospectively recruited through the Case Western Reserve University (CWRU) and University of East London (UEL) Drugs and Infancy Study (DAISY) that focused on recreational drug use in pregnant women. Women were interviewed about substance use prior to and during pregnancy and infants were seen at 1 and 4 months using standardized, normative assessments of neonatal behavior, and cognitive and motor development, including the NICU Network Neurobehavioral Scale (NNNS), the Bayley Mental and Motor Development Scales (MDI, PDI), and the Alberta Infant Motor Scales (AIMS). The sample was primarily middle class with some university education and in stable partner relationships. The majority of women recruited had taken a number of illicit drugs prior to or during pregnancy. Group differences between those polydrug using women who had specifically used MDMA during pregnancy (n=28) and those who had not (n=68) were assessed using chi-square and t-tests. MDMA and other drug effects were assessed through multiple regression analyses controlling for confounding variables. Women who used MDMA during pregnancy had fewer prior births and more negative sequelae associated with their drug use, including more health, work, and social problems. MDMA exposed infants differed in sex ratio (more male births) and had poorer motor quality and lower milestone attainment at 4 months, with a dose-response relationship to amount of MDMA exposure. These findings suggest risk to the developing infant related to MDMA exposure and warrant continued follow-up to determine whether early motor delays persist or resolve.