Fetal behavior in smoking compared to non-smoking pregnant women

ObjectiveTo determine the effects of maternal smoking on fetal spontaneous behavior and auditory processing.Methods38 fetuses of smoking (n = 18) and non-smoking (n = 20) mothers, stratified by gestational age (<37, ≥37 weeks GA), were examined at least 1 h following smoking. Observations included spontaneous fetal heart rate (FHR; 20 min) and body movements (20 min) followed by a 2 min audiotape of the mother reading a story while FHR and body movements were recorded.ResultsThere were no differences in spontaneous behaviors; full-term fetuses showed a FHR acceleration and body movement during the mother's voice. A FHR response following voice offset was limited to fetuses less than 37 weeks GA of non-smoking mothers.ConclusionFetuses less than 37 weeks GA of mothers who smoke throughout pregnancy have a delayed onset of response to the maternal voice, a subtle difference which may have implications for later language development for prematurely born infants which needs further investigation.