Association between History of Pregnancy and Liver Fibrosis Using Fibrosis-4 Index in Korean Postmenopausal Women: A Nationwide Population-Based Study

Background: The association between a history of pregnancy and liver fibrosis remains unclear. Herein, we investigated the association between reproductive factors, including a history of pregnancy and liver fibrosis, in postmenopausal Korean women.

Methods: This study used nationally representative, population-based data collected from the Korea National Health and Nutrition Examination Survey 2008-2017. Of 14,624 women with natural menopause, 11,085 with no previous history of any type of cancer, hepatitis, or chronic heavy alcohol consumption were enrolled. We investigated the reproductive factors, including a history of pregnancy, total reproductive years, age at menarche and menopause, and oral contraceptive use. Liver fibrosis was defined as a Fibrosis-4 index score ≥2.67 kg/m2.

Results: Of the study participants, 372 (3.3%) had advanced liver fibrosis. Multivariable logistic regression analysis showed that women with a history of more than one pregnancy were associated with a lower risk of liver fibrosis compared to women who had never been pregnant, after adjusting for potential confounders (adjusted odds ratio, 0.30; 95% confidence interval, 0.15-0.59). The risk of liver fibrosis did not increase significantly with an increasing number of pregnancies (P for trend=0.135). Other reproductive factors, including total reproductive years, age at menopause and menarche, and oral contraceptive use, were not significantly associated with liver fibrosis.

Conclusion: Postmenopausal women who had experienced one or more pregnancies had a reduced risk of liver fibrosis. Our findings reveal a potential protective role of pregnancy against liver fibrosis.