Intrauterine growth retardation has been reported in infants of drug abusing mothers. In the MLS Study involving 4 centers (Brown U, U Miami, U Tenn Memphis, Wayne State U), a large cohort of infants, all gestational ages(GA), were recruited to determine acute neonatal outcomes of in-utero drug exposure. From this cohort (n=11,236) we characterized the intrauterine growth of infants exposed (EXP) to C/O compared to non-exposed infants (NON). Exposure was defined as positive for C/O by maternal history or GC/MS meconium results. Marijuana, alcohol, or nicotine use was higher in the EXP group. Percentile estimates for birth weight (BW) and head circumference (HC) for each GA were determined for each group. The table shows the differences in BW and HC between EXP and NON (EXP minus NON) at 10th, 50th, and 90th percentiles; negative values indicate EXP value < NON. BW and HC of EXP were less than the NON group after 33 weeks; differences in BW were significant (p<.01). These data suggest that differences in BW associated with C/O exposure become consistent and more evident toward the latter part of pregnancy.

Table 1
Full size table