A comparison of fetal behaviour in term fetuses exposed to anticonvulsant medication with unexposed controls.

OBJECTIVE: To compare behaviour in term fetuses exposed to anticonvulsants with unexposed controls. DESIGN: An observational study. SETTING: Pregnancy Assessment Centre, University Hospital, Nottingham, UK. SAMPLE: Seventeen fetuses whose mothers were taking anticonvulsants and 94 fetuses whose mothers were on no medication between 28 and 41 weeks. METHODS: Behaviour (fetal heart rate and activity) was recorded with the use of Doppler ultrasound. The duration of recording was 60 minutes or more in all but four recordings (minimum 49 minutes). MAIN OUTCOME MEASURES: Behavioural criteria studied were: 1. the relative percentage time spent in low and high variation fetal heart rate patterns; 2. the duration and recurrence of fetal activity; 3. the number of accelerations in low and high fetal heart rate variation; and 4. the number of fetal behavioural state transitions. RESULTS: The two groups were comparable in terms of maternal age, parity. birthweight, Apgar scores and absence of neonatal problems. There was less fetal activity in the anticonvulsant group, but this was only statistically significant at 33-36 weeks in fetal heart rate pattern B (equivalent to state 2F). CONCLUSIONS: This study showed that fetuses exposed to anticonvulsant medication exhibited a trend of being less active. There were no other significant differences in behaviour. The data do not support the hypothesis of substantial differences in behaviour in fetuses exposed to anticonvulsants.

A comparison of fetal behaviour in breech and cephalic presentations at term.

OBJECTIVE: To evaluate fetal behaviour in breech and cephalic fetuses at term, using a computerised fetal behaviour program. DESIGN: An observational study. SETTING: Pregnancy Assessment Centre, University Hospital, Nottingham. SAMPLE: Twenty-six breech and 58 cephalic fetuses between 36 and 41 weeks. METHODS: Behaviour (fetal heart rate and activity) was recorded with the use of Doppler ultrasound. The duration of recording was 60 minutes or more in all but four recordings (minimum 49 minutes). MAIN OUTCOME MEASURES: Behavioural criteria studied were 1. the relative percentage time spent in low and high variation fetal heart rate patterns; 2. the duration and recurrence of fetal activity; 3. the number of accelerations in low and high fetal heart rate variation; and 4. the number of fetal behavioural state transitions. RESULTS: Breech fetuses differed from the cephalic group in that they were lighter than the cephalic fetuses (median 3105 g vs 3400 g; P < 0.01) and were born to older mothers (median maternal age 30 years vs 28 years; P < 0.01). No significant differences were found in rates of movement, numbers of accelerations and time exhibiting low and high fetal heart rate variation. However, breech fetuses exhibited significantly more state transitions (median 5.2/h vs 3.69/h; P = 0.01). CONCLUSIONS: This study shows that breech fetuses are neurologically different from their cephalic counterparts in otherwise healthy pregnancies, and that subtle behavioural differences can be demonstrated in utero using this computerised method.