Association between excessive fetal growth and maternal cancer in Shanghai, China: a large, population-based cohort study

Abstract

BACKGROUND: The prevalence of high birth weight or large for gestational age (LGA) infants is increasing, with increasing evidence of pregnancy-related factors that may have long-term impacts on the health of the mother and baby. Here, we aimed to determine the association between excessive fetal growth and subsequent maternal cancer. METHODS: We performed a population-based, prospective, cohort study to explore the association between excessive fetal growth, specifically LGA and macrosomia, and maternal cancer after childbirth. The data set was based on two registry systems: the Shanghai Birth Registry (SBR) and the Shanghai Cancer Registry (SCR), with medical records from the Shanghai Health Information Network (SHIN) as a supplement. Cox proportional hazard models were used to estimate associations. RESULTS: The prevalence of macrosomia and LGA in women who developed cancer was higher than that in women who did not develop cancer. Having a LGA child in the first delivery was associated with a subsequently increased risk of maternal cancer (HR=1.08, CI: 1.04–1.11). Additionally, in the last and heaviest deliveries, there were similar associations between the birth of LGA and maternal cancer rates (HR=1.08, 95%CI: 1.04–1.12; HR=1.08, 95%CI: 1.05–1.12, respectively). Furthermore, a substantially increased trend in the risk of maternal cancer was associated with an increase in birth weight of over 2500 g. CONCLUSIONS: Our study provided strong support for the association between LGA births and increased risks of maternal cancer. The risk for maternal cancer after birth of excessive fetal growth may need further consideration.