Frequency of thyroid dysfunction in antenatal patients visiting the tertiary care hospital.

Abstract

Objective: To determine the frequency of thyroid dysfunction and its subtypes among antenatal patients, and to analyze the relationship between thyroid dysfunction and selected sociodemographic, obstetric, and clinical parameters. Study Design: Cross-sectional Prospective study. Setting: Department of Obstetrics-Gynecology Unit-2 of Dr. Ruth K. M. Pfau, Civil Hospital Karachi, Pakistan. Period: October 1^st, 2025, to March 31^st, 2026. Methods: A total of 177 pregnant women attending the outpatient department were recruited through consecutive sampling. A detailed clinical history and relevant demographic information were recorded in a pre-designed proforma. In addition, to routine antenatal investigations, thyroid profile including serum thyroid-stimulating hormone (TSH) levels, free triiodothyronine (FT3) and free thyroxine (FT4) levels were measured in all participants. Thyroid status was categorized using trimester-specific reference ranges. Data were analyzed via SPSS. A p-value of <0.05 is considered as significant. Results: The overall prevalence of thyroid dysfunction among pregnant women was found to be 14.1% (25/177), with the majority of cases being subclinical hypothyroidism (6.78%), followed by overt hypothyroidism (2.82%), subclinical hyperthyroidism (3.39%), and overt hyperthyroidism (1.13%). A significant association was observed between thyroid dysfunction and age (p=0.008) and pregnancy-induced hypertension PIH(p=0.012), while no significant associations were observed with education, occupation, trimester, gravida, BMI, anemia, or gestational diabetes mellitus. Conclusion: The study found a moderate prevalence of thyroid dysfunction. These findings highlight thyroid dysfunction as an important antenatal health concern and support targeted screening, particularly in older pregnant women and those with pregnancy-induced hypertension, to improve maternal outcomes.