Uterine Fibroids and Hypertensive Disorders in Pregnancy: A Systematic Review and Meta-Analysis

Objective: To examine the association between uterine fibroids and the development of hypertensive disorders in pregnancy. Data sources: Cochrane, Embase, PubMed, MEDLINE, Scopus, and Web of Science databases were searched from inception through April 2023. Study Selection and Synthesis: Cohort, case-control, or case series studies including uterine fibroid status and hypertensive disorders of pregnancy status were included. The comparison group was pregnant women without uterine fibroids. Inverse-variance weighted random effects models were used to pool RR and OR estimates separately. Age and BMI were explored as potential sources of heterogeneity using inverse-variance weighted meta-regression. Main Outcomes: Hypertensive disorders of pregnancy (HDP) defined as gestational hypertension, pre-eclampsia, eclampsia, superimposed preeclampsia, or hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome. Results: A total of 17 studies were included (Total N=1,374,395 participants, N=64,968 with uterine fibroids). Thirteen studies were retrospective cohorts and four were case-control studies. Women with uterine fibroids had a significantly higher risk of hypertensive disorders in pregnancy compared to women without uterine fibroids with RR 1.74 (95% CI 1.33-2.27, p<0.01), and OR 2.87 (95% CI 1.38-5.97, p<0.01), in cohort studies and case-control studies, respectively. In meta-regression analyses, age did not significantly change the positive association between uterine fibroids and hypertensive disorders in pregnancy. Conclusion: Uterine fibroids were associated with an increased risk of hypertensive disorders of pregnancy when all available literature was synthesized, including when shared risk factors are examined in meta-regression analyses. Relevance: If confirmed in future studies, investigations into the mechanisms of this association are needed as this finding potentially has implications for risk stratification and monitoring for hypertensive disorders of pregnancy in this population. Key Words: Uterine fibroids, Leiomyoma, Preeclampsia, hypertensive disorders in pregnancy.