Young Women’s HDL Cholesterol Changes Differ by Parity Status, Race and Pre-Pregnancy HDL

Abstract

Abstract Objectives Longitudinal analyses have identified that first pregnancy is associated with a 3–4 mg/dl selective decrease in high-density lipoprotein-cholesterol (HDL-C) concentration. This study examined whether HDL-C concentration changes vary by pre-pregnancy demographic or cardiometabolic factors. Methods This is a secondary analysis of the NHLBI Growth and Health Study in which girls were studied from 9 to 29 years of age. Girls with lipid measurements prior to (mean age ∼17) and after (mean age ∼23) their first birth (parous) were compared with a nulliparous group with lipid assessments at similar ages (∼16 and ∼25 years). Results 202 nulliparous and 199 parous participants were analyzed (52% black, mean age 16.6 at initial measurement). The parous group was more likely to be black (66% vs. 38%, P < 0.0001), but did not differ on initial BMI, % body fat, or HDL-C. HDL-C change was not related to gestational factors (gestational weight gain, infant birthweight (both P > 0.3)). Adjusting for concurrent change in BMI, race and time between measurements, the parous group HDL-C decreased by −3.4 mg/dl while the nulliparous HDL-C did not change (−0.1 mg/dl, P = 0.004 for difference). Adjusted HDL-C changes were negatively associated with initial HDL-C (beta: −0.42, P < 0.0001), but not with initial BMI (P = 0.13) or age (P = 0.18). Parity status and race altered the relationship of initial HDL-C with changes in HDL-C (p for 3-way interaction <0.05). In particular, whites with initial HDL-C ≥ 50 mg/dl experienced pregnancy-specific decreases in HDL-C (−7.0 mg/dl parous vs. no significant change in nulliparous, P < 0.0001). In blacks with initial HDL-C ≥ 50 mg/dl, HDL-C significantly declined in both the parous (−6.9 mg/dl) and nulliparous (−5.4 mg/dl) groups (P = 0.35 for parity difference). In women of both races with low initial HDL-C (<50 mg/dl), HDL-C increased or did not change. Conclusions Young adult changes in HDL are not associated with gestational factors, but are strongly associated with race, parity status, changes in BMI and initial HDL. In particular, white young women with high HDL experience major pregnancy-related decreases in HDL, while black young women with high HDL are at risk of significant HDL declines, regardless of parity. Impacts on cardiometabolic outcomes should be examined. Funding Sources NIH/NHLBI.