Elevated dyslipidemia during pregnancy can adversely affect maternal and child health. It not only increases the risk of preeclampsia, gestational diabetes mellitus (GDM) , hypertriglyceridemic pancreatitis, late abortion, premature delivery and macrosomia, but also significantly increases the risk of postnatal cardiovascular disease.

To analyze the distributional characteristics of dyslipidemia in the first, second and third trimesters of pregnancy and the predictive value of early lipid levels for dyslipidemia in the second and third trimesters of pregnancy.

This was a single-center retrospective study, which included singleton pregnant women who were enrolled in Beijing Obstetrics and Gynecology Hospital, Capital Medical University from January 2018 to June 2019 for obstetrics checkups until delivery. Clinical data and lipid data [total cholesterol (TC) , triacylglycerol (TG) , low-density lipoprotein cholesterol (LDL-C) , and high-density lipoprotein cholesterol (HDL-C) ] were collected in the first, second and third trimesters of pregnancy. The reference range of lipids in department of obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University was used as the diagnostic standard for dyslipidemia, including high total cholesterolemia, high triacylglycerolemia, low HDL-cholesterolemia and high LDL-cholesterolemia. The correlation between lipid levels in the first trimester of pregnancy and dyslipidemia in the second and third trimesters of pregnancy was analyzed by using binary Logistic regression, and the receiver operating characteristics (ROC) curves of the subjects were plotted to obtain the area under ROC curve (AUC) , to evaluate the predictive value of the lipid levels in the first trimester of pregnancy for dyslipidemia in the second and third trimesters of pregnancy, and to determine the optimal cut-off value according to the sensitivity and specificity.

A total of 8 511 singleton pregnant women were included in the study, with an average age of (31.7±3.9) years and an average pre-pregnancy BMI of (21.7±3.2) kg/m². Among them, 988 (11.6%) were of low pre-pregnancy body mass, 5 568 (65.4%) were of normal pre-pregnancy body mass, 1 271 (14.9%) were overweight, 366 (4.3%) were obese, 1 415 (16.7%) were with GDM, and 650 (7.6%) were with hypertensive disorders of pregnancy (HDP) . The levels of TC, TG and LDL-C in the second and third trimesters of pregnancy were higher than those in the first trimester of pregnancy (P<0.05) . The level of HDL-C in the third trimester of pregnancy was higher than that in the first trimester of pregnancy, but lower than that in the second trimester of pregnancy (P<0.05) . The prevalence of dyslipidemia in the first trimester of pregnancy was 23.4% (1 990/8 511) , and the prevalence of dyslipidemia in the second and third trimesters of pregnancy was lower than that in the first trimester of pregnancy (P<0.05) . The prevalence of dyslipidemia in overweight and obese pregnant women in the first trimester of pregnancy was higher than that in pregnant women with normal pre-pregnancy body mass, but there was no statistical difference in the prevalence of dyslipidemia in the third trimester of pregnancy (P>0.05) . The prevalence of dyslipidemia in first and second trimesters of pregnancy in the GDM group was higher than that in the non-GDM group, and the prevalence of dyslipidemia in first, second and third trimesters of pregnancy in HDP group was higher than the non-HDP group (P<0.05) . After excluding pregnancy comorbidities and complications that may affect blood lipids, the optimal cut-off values for predicting dyslipidemia in the second trimester of pregnancy were TC of 4.485 mmol/L (AUC=0.854) , TG of 1.325 mmo/L (AUC=0.864) , HDL-C of 1.275 mmol/L (AUC=0.908) , and LDL-C of 2.265 mmol/L (AUC=0.823) , respectively; the optimal cut-off values for predicting dyslipidemia in the third trimester of pregnancy were TC of 4.485 mmol/L (AUC=0.809) , TG of 1.145 mmol/L (AUC=0.833) , HDL-C of 1.285 mmol/L (AUC=0.851) , LDL-C of 2.195 mmol/L (AUC=0.766) .

The prevalence of dyslipidemia did not increase during pregnancy. There were significant differences in the prevalence of dyslipidemia during pregnancy among pregnant women with different pre-pregnancy BMI, between GDM and non-GDM pregnant women, between HDP and non-HDP pregnant women, respectively. The blood lipid level in the first trimester was helpful to predict the occurrence of dyslipidemia in the second and third trimesters of pregnancy.