Objective: To determine degree of exposure to cocaine in-utero by analysis of BZE in hair at birth, and relationship to neurodevelopmental outcome at 3 years and above, under similar socioeconomic status.

Design: Prospective longitudinal follow-up of infants with in-utero cocaine exposure (IUCE) determined by BZE hair analysis by modified RIA and/or positive urine toxicology test at birth. Forty-eight children (24 females, 24 males) with IUCE were followed by a multi-disciplinary team in a tertiary care developmental clinic. Seventy-three percent of children were cared for by their biological mother, and 27 percent had foster care. Patients had serial neurodevelopmental assessments through to above three years of age.

Main Results: Cocaine exposure was determined by BZE hair analysis. Forty were hair positive and eight urine positive. Thirty-three infants were both hair and urine positive. BZE levels were determined in ng/g/hair and then corrected for body surface area, i.e. BZS in ng/g/m2. Mean BZS level was 2525 ng/g (range 99 to 6245 ng/g); mean BZS level was 15607 ng/g/m2 (range 521 to 53335 ng/g/m2). Developmental and behavioral outcome were determined using age-appropriate standardized tests (CATS/CLAMS,BSID-II, Stanford-Binet IV, Slosson Intelligence Test-R, Child Behavior Checklist) and physical /neurological examination. NDO was determined by grading A to D based on developmental quotients (DQ) and number of domains affected, including motor, cognitive, language and behavior as follows: (A) All areas normal with DQs>85; (B) one area affected with DQ<85; (C) two areas affected with DQ <85; and(D)More than two areas affected with DQ <85. Of the 33 patients hair and urine positive, 21 were classified as A+B and had a mean BZS level of 13577; 12 were classified grade C+D and had a mean BZS level of 21217, which was statistically significantly higher. Of the seven patients hair positive and urine negative, all were classified grade A+B. Of the eight hair negative and urine positive, all were classified as grade A+B.

Conclusions: Degree of gestational cocaine exposure may be measured by BZE in hair and BZS at birth.

BZS levels appear to be important predictors for NDO at 3 years. Children with multiple NDO deficits had significantly higher BZS (21215) when compared to those with normal or minimal problems (13577).

BZS levels at birth may be helpful for deciding on early intervention in children exposed to cocaine in-utero.