Study population
The prospective cohort was recruited in FUXING Hospital affiliated to Capital Medical University in Beijing, China from November 2018 to January 2020. Inclusion criteria were: 1) naturally conceived; 2) singleton pregnancy. Exclusion criteria were: 1) women with diabetes before pregnancy; 2) women with autoimmune disease; 3) women who take drugs that affect lipid metabolism. Finally, a total of 908 participants were enrolled in this study. They were followed from recruitment to 42 days postpartum. This study was approved by the Ethics Committee of Capital Medical University (2012SY29) and abide by the Declaration of Helsinki principles, and all participants have signed the informed consent after being fully informed at the first visit. This work was supported by the National Natural Science Foundation of China [No. 81872608 and No.8207121162].