The impact of patterns of drug use during pregnancy on birthweight (BW) has not been reported. An objective of this study was to quantify history of drug use during pregnancy by a detailed maternal inventory of substance use (MISU) and to assess relation between cocaine use and BW. Women at 4 sites (Brown U, U of Miami, U of Tenn Memphis, Wayne State U) with a history of cocaine/opiate(C/O) use during pregnancy or presence of C/O metabolites in meconium (exposed(EXP) group n=538) were matched by race, GA and infant sex (comparison group(COM) n=731). The MISU was administered at the 1 mo clinic visit. History of any substance use was assessed by 4 time periods: 3 mos prior to pregnancy, and during each trimester. Use was categorized as high (daily or 3-6 d/wk), moderate (1-2 d/wk), low (1-3 d/mo) or none per time period. To assess the effect of cocaine on BW, cocaine use during 3 mo prior to pregnancy or first trimester was compared with use in 2nd and 3rd trimesters among 245 women in EXP group and 412 in COM group who delivered at term.

Results: Tobacco, alcohol and marijuana use was noted in the COM group, but use was significantly lower than EXP group (p<.05). Daily use during 1st and 3rd trimester was as follows: tobacco 65 & 59% in EXP and 25 & 19% in COM; alcohol 12 & 7% in EXP and 2 & 0.6% in COM, marijuana 4 & 1% in EXP and 1 & 0.4% in COM. The effect of patterns of cocaine use on BW indicate COM infants were heavier (p<.01) than each of the EXP groups. Table

Table 1
Full size table

Conclusion: Cocaine EXP infants were lighter than COM infants; within EXP group there was no association between quantity of C use by the MISU during pregnancy and BW.