Gestational Weight Gain,Breastfeeding And Infant Growth Trajectories:A Birth Cohort Study

Objectives We aim to describe early childhood growth trajectories,and to assess the association between gestatonal weight gain,breastfeeding and growth patterns.Methods Our research was based upon Ma'anshan Birth Cohort Study.In this study,3 474 pregnant women consecutively enrolled from May 2013 to September 2014 in Ma'anshan Maternal and Child Health(MCH)clinics when they did first physical examination during pregnancy.Excluding subjects of termination of pregnancy(n = 162),twin pregnancy(n = 39),there were 3 273 single live births in MABC study.Excluding subjects without children gender information(n = 6),infants with?3 BMI observations(n = 210),3 057 parent-singleton-child pairs were enrolled for the final data analysis.Studies have shown that most children who are born small for gestational age(SGA,defined as having birth weight below the 10 th percentile at a particular gestational week)experience catch-up growth in infancy,for this reason,SGA children were excluded(n = 294)in a sensitivity analysis.Maternal BMI was grouped into normal weight,underweight,overweight or obesity;Gestational weight gain(GWG)was classified on the basis of Institute of Medicine guidelines(IOM).As for children,measurements of body length and weight from birth to 2 years were gathered from medical records.BMI z-scores were computed with reference to the WHO standards.Latent class growth model was used to estimate BMI growth trajectory.The multinominal logistic regression models are used for testing the relationship between GWG,breastfeeding and infant BMI growth trajectory.Results According to the results of our Latent class growth model,the 3 057 infants showed four obvious growth trajectories: “fast trajectory”(16.7%),“slow trajectory”(25.3%),“catchup trajectory”(4.1%)and “normal trajectory”(53.9%).Excessive GWG predicted fast growth trajectory(OR = 1.51,95%CI: 1.13~2.03),and inadequate GWG were positive related to slow trajectory(OR = 1.58,95%CI: 1.22~2.05);Complementary feeding or bottle feeding were negative related to the fast growth trajectory(OR = 0.55,95%CI: 0.41 ~ 0.73;OR = 0.40,95%CI: 0.29 ~ 0.55,respectively),after adjusting for confounding factors,the relationship still holds(OR = 0.58,95%CI: 0.41~0.83;OR = 0.41,95%CI: 0.27~0.61).After excluding the 294 SGA children,and the three-class model provided the optimal model fit and interpretability,these 2 736 infants showed three distinct growth trajectories: “normal trajectory”(n = 1 624,58.8%),“fast trajectory”(n = 454,16.4%)and “slow trajectory”(n = 685,24.8%);However,no catch up trajectory occurs after excluding of SGA.The results of sensitivity analysis showed that both GWG and breastfeeding have significant differences with infant BMI trajectories,and with no surprise that this analysis indicated similar effects.Conclusion Our results indicated that GWG and breastfeeding may make a difference to infant BMI growth trajectories.