Global Prevalence of Thyroid Dysfunction Among Pregnant Women, 2003-2024: A Systematic Review and Meta-analysis

IntroductionThyroid dysfunction is the second most common endocrine disorder globally, posing a significant public health challenge during pregnancy after gestational diabetes mellitus. Given the wide regional variations in reported data, this systematic review and meta-analysis aims to determine a definitive pooled prevalence of thyroid dysfunction among pregnant women to better inform clinical practice.MethodsThis study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and is registered in PROSPERO with registration protocol number of CRD42024581530. Five primary databases-PubMed, Embase, Google Scholar, Scopus, and Web of Science were searched to identify relevant studies. Study quality was assessed using the Joanna Briggs Institute appraisal tool. Data were extracted into Microsoft Excel and analyzed using STATA (version 17) software. Pooled prevalence estimates for thyroid dysfunction and its primary components were determined using a random-effects model. Heterogeneity was measured via I² statistics, and publication bias was evaluated using Funnel plots and Egger's test.ResultA total of 48 studies were included in this systematic review and meta-analysis. The pooled prevalence of thyroid dysfunction among pregnant women was 16.12% (95% CI: 13.97, 18.27, I²=98.16, p<0.001) using random effect model. The pooled prevalence of subclinical hypothyroidism, overt hypothyroidism, subclinical hyperthyroidism, and overt hyperthyroidism were 11.53% (95% CI: 8.954, 14.095), 3.29 (95% CI: 2.242, 4.330), 1.56% (95% CI: 0.809, 2.312), and 1.13% (95% CI: 0.363, 1.888) respectively.ConclusionThis meta-analysis found that thyroid dysfunction is a significant health concern among pregnant women affecting a significant proportion across studies. Subclinical hypothyroidism was identified as the most common subtype, while overt hyperthyroidism was comparatively rare.