Importance: Statins are the drug class most commonly used to treat hyperlipidemia. Recently, they have been used during pregnancy for the prevention or treatment of preeclampsia. However, the safety of statin use during pregnancy has been questioned, and the sample sizes of most previous studies have been small.
Objective: To examine the perinatal outcomes among offspring associated with maternal use of statins during pregnancy.
Design, setting, and participants: This retrospective cohort study included 1 443 657 pregnant women 18 years of age or older with their first infant born during the period from January 1, 2004, to December 31, 2014. Data for this study were taken from the Taiwan National Health Insurance Research Database. Statistical analysis was performed from April 7, 2020, to July 31, 2021.
Exposures: Maternal statin use during pregnancy.
Main outcomes and measures: Women who have received a diagnosis of hyperlipidemia before pregnancy and who were receiving prescription statins during pregnancy were the statin-exposed group. Data on congenital anomalies, birth weight, gestational age, preterm birth, low birth weight, very low birth weight, fetal distress, and Apgar score were compared between participants with and partcipants without statin exposure during pregnancy. Risk ratios (RRs) were calculated by multivariable analyses using Poisson regression models to adjust for potential confounders. Subgroup analysis was performed to compare offspring of women who used statins for more than 3 months prior to pregnancy and maintained or stopped statin use after pregnancy.
Results: A total of 469 women (mean [SD] age, 32.6 [5.4] years; mean [SD] gestational age, 38.4 [1.6] weeks) who used statins during pregnancy and 4690 age-matched controls (mean [SD] age, 32.0 [4.9] years; mean [SD] gestational age, 37.3 [2.4] weeks) with no statin exposure during pregnancy were enrolled. After controlling for maternal comorbidities and age, low birth weight was more common among offspring in the statin-exposed group (RR, 1.51 [95% CI, 1.05-2.16]), with a greater chance of preterm birth (RR, 1.99 [95% CI, 1.46-2.71]), and a lower 1-minute Apgar score (RR, 1.83 [95% CI, 1.04-3.20]). Congenital anomalies were not associated with statin exposure during pregnancy. In addition, multivariable analysis showed that there was no association between statin use for periconceptual hyperlipidemia and adverse perinatal outcomes among women who had used statins prior to pregnancy.
Conclusions and relevance: This study suggests that statins may be safe when used during pregnancy because there was no association with congenital anomalies, but caution is needed because of an increased risk of low birth weight and preterm labor. The data also suggest that statins could be safely used during pregnancy for women with long-term use of statins before pregnancy.