[Impact of pre-pregnancy body mass index on baby's physical growth and nutritional status]

To explore the impact of pre-pregnancy body mass index on baby's physical growth and nutritional status.

A total of 491 pairs of mother-infant were divided into 3 groups according to mother's pre-pregnancy body mass index (BMI): a pre-pregnancy low BMI group (BMI<18.5 kg/m², n=93), a pre-pregnancy normal BMI group (18.5 kg/m² ≤ BMI<24.0 kg/m², n=326), and a pre-pregnancy high BMI group (BMI ≥ 24.0 kg/m², n=72). Analysis of variance of repeated measurement data and the median percentage methods were used to compare the physical growth and nutritional status of babies in different groups.

Baby's weight in the high BMI group were higher than that in the normal BMI and the low BMI group (F=3.958, P=0.020). The incidence of malnutrition in the low BMI group showed a tendency to decline along with the months (χ²=5.611, P=0.018), the incidence of overweight and obesity in the high and the normal BMI groups displayed a tendency to decline along with the months (χ²=18.773, 53.248, all P<0.001). Baby in the low BMI group had higher incidence of malnutrition while baby in the high BMI group had higher incidence of overweight and obesity.

Pregnancy BMI was correlated with the growth of baby. Too high or too low prepregnancy BMI exerts harmful effect on baby's weight and nutritional status. Medical workers should strengthen the education on women's pre-pregnancy to remind them keeping BMI at normal level.