Human fetal behaviour and maternal cocaine use: a longitudinal study.

This paper reports a series of ultrasound observations on a human fetus from 21 weeks of gestational age at two weekly intervals to term. The mother, until 18 weeks of gestational age, was a user of cocaine but after this age used cocaine only once at 31 weeks gestation. The behaviour of this fetus was compared to a group of 10 similar aged fetuses who were not exposed to cocaine. Exposure to cocaine resulted in prolonged periods of inactivity interspersed with periods of increased general activity and an increased number of startles. This was particularly evident immediately following exposure to cocaine but behaviour appeared to become more normal with time as the mother stopped using cocaine. The behavioural states of the cocaine exposed fetus were different from unexposed fetuses. Longer periods were spent in States 1F and 4F and less time in State 2F. Furthermore the incidence of periods where no states were observed was considerably higher. These observations demonstrate that maternal cocaine use disrupts the behaviour of the fetus indicating a direct effect on the CNS. The value of prenatal behavioural observations to assess the effects of neurotoxic agents is demonstrated.