Associations between gestational weight gain and adverse neonatal outcomes: a comparison between the US and the Chinese guidelines in Chinese women with twin pregnancies

BACKGROUND: Appropriate gestational weight gain (GWG) is essential for maternal and fetal health. For twin pregnancies among Caucasian women, the Institute of Medicine (IOM) guidelines can be used to monitor and guide GWG. We aimed to externally validate and compare the IOM guidelines and the recently released guidelines for Chinese women with twin pregnancies regarding the applicability of their recommendations on total GWG (TGWG). METHOD: A retrospective cohort study of 1534 women who were aged 18–45 years and gave birth to twins at ≥ 26 gestational weeks between October 2016 and June 2020 was conducted in Guangzhou, China. Women's TGWG was categorized into inadequate, optimal, and excess per the IOM and the Chinese guidelines. Multivariable generalized estimating equations logistic regression was used to estimate the risk associations between TGWG categories and adverse neonatal outcomes. Cohen’s Kappa coefficient was calculated to evaluate the agreement between the IOM and the Chinese guidelines. RESULTS: Defined by either the IOM or the Chinese guidelines, women with inadequate TGWG, compared with those with optimal TGWG, demonstrated higher risks of small-for-gestational-age birth and neonatal jaundice, while women with excess TGWG had a higher risk of delivering large-for-gestational-age infants. The agreement between the two guidelines was relatively high (Kappa coefficient = 0.721). Compared with those in the optimal TGWG group by both sets of the guidelines, women classified into the optimal group by the Chinese guidelines but into the inadequate group by the IOM guidelines (n = 214) demonstrated a statistically non-significant increase in the risk of all the adverse neonatal outcomes combined. CONCLUSIONS: The IOM and the Chinese guidelines are both applicable to Chinese women with twin pregnancies. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-023-15008-z.