Maternal intelligence quotient and motor development in early childhood: The mediating role of mother's education.

AIM: To examine the association between maternal intelligence quotient (IQ) and early childhood motor development and whether maternal education mediates this relationship. METHODS: Data were collected prospectively in the Ma'anshan Birth Cohort study. Maternal IQ was assessed using the Wechsler Adult Intelligence Scale-Revised by China (WAIS-RC). Information on baseline characteristics and maternal education was obtained from questionnaires and medical records. The study outcome was motor development evaluated at 18 months by the Third Edition of Ages and Stages Questionnaire. Logistic regression analyses and mediation analyses were used. RESULTS: Of 2739 valid subjects (84% follow-up), the rate of developmental delay was 3.1% in the gross motor domain and 6.2% in the fine motor domain. The mean value for maternal IQ was 96.2 (standard deviation 10.6). About 40.3% of the mothers had secondary education or less, while 59.7% had a college education. Mothers with higher IQ had a significantly higher educational level and had children with better motor development. Maternal education significantly mediated the association between maternal IQ and fine motor development. There was a direct effect of maternal IQ on gross motor development, but the mediation effect of maternal education was not found. CONCLUSIONS: Maternal IQ was associated with motor development. Maternal education played an important role in reducing the disparities in fine motor development among children of different maternal IQs.

Pre-pregnancy BMI, gestational weight gain and breast-feeding: a cohort study in China.

OBJECTIVE: The purpose of the present study was to examine the influence of maternal pre-pregnancy BMI and gestational weight gain (GWG) on initiation and duration of infant breast-feeding in a prospective birth cohort study. DESIGN: Breast-feeding information was collected at 1, 3, 6 and 12 months postpartum. The association of pre-pregnancy BMI and GWG with delayed lactogenesis II and termination of exclusive breast-feeding was assessed with logistic regression analysis. The risk of early termination of any breast-feeding during the first year postpartum was assessed with Cox proportional hazards models. SETTING: Urban city in China. SUBJECTS: Women with infants from the Ma'anshan Birth Cohort Study (n 3196). RESULTS: The median duration of any breast-feeding in this cohort was 7·0 months. Pre-pregnancy obese women had higher risks of delayed lactogenesis II (risk ratio=1·89; 95 % CI 1·04, 3·43) and early termination of any breast-feeding (hazard ratio=1·38; 95 % CI 1·09, 1·75) adjusted for potential maternal and infant confounders, when compared with normal-weight women. No differences in breast-feeding initiation or duration of exclusive breast-feeding according to pre-pregnancy BMI were found. Moreover, GWG was not associated with any poor breast-feeding outcomes. CONCLUSIONS: The present study indicated that pre-pregnancy obesity increases the risks of delayed lactogenesis II and early termination of any breast-feeding in Chinese women.