Long-term effects of MPA on human progeny: intellectual development.

Tests of verbal and spatial ability were done on 450 boys and 537 girls in their late teens of whom 73 and 97, respectively, had been exposed in utero to MPA. Exposed boys achieved higher raw scores than controls on verbal and spatial tests but the differences were explained by their more favorable demographic and social characteristics. Exposed girls did not differ from controls. Although, mothers of exposed boys reported that their offspring talked and walked later than controls, our results support the hypothesis that intrauterine exposure to MPA at contraceptive doses has no long-term effect on intellectual development.