Impact of parity on gestational diabetes mellitus in Chinese women: a retrospective cohort study.

BACKGROUND

The prevalence of gestational diabetes mellitus (GDM) has risen significantly in recent years, yet the association between parity and GDM remains poorly understood. This study aimed to evaluate the impact of parity on GDM while exploring other contributing factors.

METHODS

We performed a population-based retrospective cohort study using data from women who delivered in Baoan District, Shenzhen, from January 2019 to December 2023. GDM was diagnosed through oral glucose tolerance testing (OGTT). Multivariable logistic regression models were applied to examine parity-GDM associations.

RESULTS

A total of 198,237 women (including 89,792 primiparae and 108,445 multiparae) were included. Higher parity was found to be inversely associated with the development of GDM (OR [95%CI]: 0.92 [0.87-0.96] for parity = 1, OR [95%CI]: 0.83 [0.77-0.90] for parity ≥ 2). Further, stratified analyses revealed that this association was more significant in women under 30 years of age (P interaction < 0.05).

CONCLUSIONS

The present findings revealed that women with higher parity had a lower probability of GDM, particularly among younger women. These results suggest that clinicians implement enhanced glycemic monitoring for nulliparous women of advanced maternal age. When promoting desired family size, emphasizing childbearing during earlier reproductive years may reduce GDM risk profiles.