Effect of alanine aminotransferase in early pregnancy on neonatal birth weight / 中华内分泌代谢杂志

ABSTRACT

Objective:To investigate the effect of alanine aminotransferase(ALT) level in early pregnancy and its interaction with maternal body mass index(BMI) on neonatal birth weight.Methods:Data of full-term singleton delivery mother-infant pairs from 2014 to 2016 in Wenzhou were collected. The exposure(ALT>40 U/L) and non-exposure(ALT≤40 U/L) groups were matched using 1∶4 propensity score matching. Logistic regression analysis was used to analyze the relationship between increased ALT level in the first trimester and abnormal birth weight as well as the effect of its interaction with BMI on abnormal birth weight.Results:Multivariate analysis showed that the risks of macrosomia and large for gestational age(LGA) in pregnant women with ALT>40 U/L were 1.584(95% CI 1.323-1.896) and 1.292(95% CI 1.142-1.461) compared with those with ALT≤40 U/L. ALT in the first trimester displayed an additive interaction with BMI on the risk of macrosomia [the relative excess risk due to interaction( RERI)=2.032, 95% CI 0.307-3.757, the attributable proportion due to interaction( API)=0.448, 95% CI 0.221-0.684, the synergy index( S)=2.348, 95% CI 1.274-4.324]. In addition, there was no interaction between ALT and BMI on the risk of LGA, and nor did the association of ALT in the first trimester with low birth weight or small for gestational age exist. Conclusion:ALT>40 U/L in the first trimester increases the risk of high birth weight, especially in overweight or obese pregnant women in the first trimester. Therefore, it is suggested to strengthen the monitoring of ALT level in obese pregnant women during the first trimester.