Neurodevelopmental trajectories in children with cleft lip and palate: A longitudinal study based on the Japan Environment and Children's Study

Cleft lip and/or palate (CL/P), the most prevalent congenital anomaly, is understood to negatively affect a wide range of child development. Since the concept remains controversial, because most published work is from cross-sectional studies, we examined the neurodevelopmental trajectories in participants with CL/P through a longitudinal comparison with the general population during early childhood using data from a nationwide birth cohort study in Japan. The linear mixed models for each domain of the Ages and Stages Questionnaire, third edition (ASQ-3), were used to detect differences in standardised mean scores between groups. The ASQ-3 is a general neurodevelopmental screening tool comprising communication, gross motor, fine motor, problem-solving, and personal-social domains. Participants' neurodevelopment was determined semi-annually from 6 to 36 months of age. The trajectories of standardised mean scores in each domain showed several significant differences between the control and CL/P groups, with the maximum difference at 24 months of age in the communication domain. Indeed, CL/P was associated with significantly lower scores in the communication (coefficient: -3.31, 95% CI: -5.09 to -1.14), problem-solving (coefficient: -3.13, 95% CI: -5.07 to -1.18), and personal-social domains (coefficient: -1.99, 95% CI: -3.87 to -0.11). Trajectories of ASQ-3 scores suggest neurodevelopmental delays in children with CL/P.

Association of prenatal maternal blood lead levels with birth outcomes in the Japan Environment and Children's Study (JECS): a nationwide birth cohort study

BACKGROUND

Despite dramatic declines in prenatal maternal blood lead levels (BLLs) in most developed countries, little is known about the effects of extremely low-level (<1.0 µg/dL) lead exposure on fetal growth.

METHODS

We measured maternal BLL during the second or third trimester of pregnancy and assessed birth outcomes, including birthweight, preterm birth (<37 gestational weeks) risk, small for gestational age births (SGA; birthweight <10th percentile) and low birthweight (LBW; <2500 g). The association between birthweight and maternal BLL was estimated using linear and quadratic spline models. Multivariable logistic models were used to examine the risk of binary responses.

RESULTS

From 103 099 pregnant women, 20 000 blood samples were randomly selected for analysis. The maternal BLL range was 0.16-7.4 µg/dL, and the median was 0.63 µg/dL. After adjusting for covariates, the linear model showed that each 0.1 μg/dL increase in maternal BLL was associated with a 5.4 g decrease in mean birthweight [95% confidence interval (CI), 3.4 to 7.5 g]. The risk of SGA [adjusted odds ratio (aOR), 1.03; 95% CI, 1.02 to 1.05) and LBW (aOR, 1.03; 95% CI, 1.02 to 1.05) increased, whereas the risk of preterm delivery did not (aOR, 0.99; 95% CI, 0.97 to 1.02).

CONCLUSIONS

Even at a maternal BLL below 1.0 µg/dL, prenatal lead exposure was associated with decreased birthweight and increased risk of SGA and LBW, but not preterm delivery. The adverse effect estimates of prenatal lead exposure on birth outcomes were quantitatively small and clinically limited at this low level.