Prevalence of Subclinical Hypothyroidism in Pregnant Females in Three Trimesters: A Cross-Sectional Study

Background: Subclinical hypothyroidism (SCH) in pregnancy is associated with multiple adverse obstetrical and fetal outcomes i.e. preterm labor, miscarriage, fetal distress& preterm birth. The present study was therefore planned to identify high occurrence rate of SCH positive cases (Pregnant females coming to ANMC & Hosp for antenatal care) & to highlight that TSH screening should be included in routine antenatal screening. Objective: To identify SCH cases in pregnancy, coming for antenatal workup in Al Nafees medical college & Hospital Islamabad, Pakistan. Material and Methods: In this study random screening of 150 pregnant females for serum TSH levels was done. Females were divided in to three equal groups i.e. 50 females in each trimester. Serum TSH levels was done by ELISA and American thyroid association guidelines (ATA) for TSH levels was taken as reference values. Results: The data obtained from this study indicated that 34.7% positive SCH cases. Mean and SD of study variables i.e. age, parity and Hb were also compared in three trimesters which showed insignificant variation. Conclusion: It was evident from our study results that SCH is prevalent in our local population. This study reinforces that TSH screening should be included in routine antenatal screening. This will help us to avoid maternal and fetal adverse outcomes associated with SCH as documented in various studies on thyroid disorders.