The associations between cigarette smoking before and during pregnancy and maternal body size (pre-pregnancy weight status, end of pregnancy weight status, weight gain during pregnancy) and newborn size (birth weight, length, head circumference, arcomial circumference), as well as birth modus, were tested in 7803 single full-term births in Vienna. Nicotine consumption before and during pregnancy was found to be associated with smaller and lighter newborns, although maternal weight status and weight gain during pregnancy was signi.cantly higher in smokers. Furthermore, a higher incidence of Caesarean sections was found in smokers. A reduction in the number of daily smoked cigarettes was associated with a lower percentage of low weight newborns (<2500 g).
SummaryThe impact of maternal height, pre-pregnancy weight status and gestational weight gain on fetal growth patterns and newborn size was analysed using a dataset of 4261 singleton term births taking place at the Viennese Danube Hospital between 2005 and 2013. Fetal growth patterns were reconstructed from three ultrasound examinations carried out at the 11th/12th, 20th/21th and 32th/33th weeks of gestation. Crown–rump length, biparietal diameter, fronto-occipital diameter, head circumference, abdominal transverse diameter, abdominal anterior–posterior diameter, abdominal circumference and femur length were determined. Birth weight, birth length and head circumference were measured immediately after birth. The vast majority of newborns were of normal weight, i.e. between 2500 and 4000 g. Maternal height showed a just-significant but weak positive association (r=0.03: p=0.039) with crown–rump length at the first trimester and with the majority of fetal parameters at the second trimester (r>0.06; p<0.001) and third trimester (r>0.09; p<0.001). Pre-pregnancy weight status was significantly positively associated with nearly all fetal dimensions at the third trimester (r>0.08; p<0.001). Maternal height (r>0.17; p<0.001) and pre-pregnancy weight status (r>0.13; p<0.001), but also gestational weight gain (r>0.13; p<0.001), were significantly positively associated with newborn size. Some of these associations were quite weak and the statistical significance was mainly due to the large sample size. The association patterns between maternal height and pre-pregnancy weight status with fetal growth patterns (p<0.001), as well as newborn size (p<0.001), were independent of maternal age, nicotine consumption and fetal sex. In general, taller and heavier women gave birth to larger infants. This association between maternal size and fetal growth patterns was detectable from the first trimester onwards.
