Endocrine Abstracts

Introduction: Sri Lanka is endemic for goiters and recent studies show a high prevalence of thyroid dysfucntion among the population. However, data on thyroid dysfuntion among the general population and pregnant women in Sri Lanka is limited. Thyroid dysfunction is associated with adverse pregnancy outcomes. Furthermore, pregnancy related physiological changes increase the risk of thyroid dysfucntion. However, women in Sri Lanka are not routinely screened during pregnancy for thyroid dysfunction.

Methods: A descriptive cross sectional study was conducted among 872 women who received antenatal care and underwent universal first trimester or early second trimester thyroid status screening at a tertiary care centre in Sri Lanka over a period of one year. Pregnancy records were analyzed to extract data on past medical history, thyroid status, and pregnancy outcomes.

Results: 872 women underwent screening with TSH at the booking visit. Pregnancy specific reference ranges were used (0.1-2.5 mIU/ml for first trimester and 0.2-0.3 mIU/ml for second trimester). Among them, 91.4%(n= 797) were euthyroid. Two women had been diagnosed with Graves disease prior to pregnancy and were on treatment with with oral antithyroid medications. Remaining 8.6%(n= 73) of the population were found to be hypothyroid. Among women with hypothyroidism, 21.9%(n= 16) had been diagnosed prior to pregnancy while remaing 80.1%(n= 57) were newly diagnosed during antenatal screening. Prevalaence of subclical hypothyroidism among the population was 5.4%(n= 47) and prevalence of overt hypotyroidism was 3%(n= 26). 57.5%(n= 42) of women with hypothyroidism were positive for TPO antibodies. One woman had undergone thyroidectomy due to papillary thyroid carcinoma while 2 women who had undergone thyroidectomy for goiters prior to pregnancy. Prevalence of goiters among the population was 6%(n= 52). Women with overt hypothyroidism had a higher risk of foetal graowth restriction (P=0.04), and neonatal intensive care admission (P=0.02). There were no statistically significant differences between pregnancy outcomes of women with euthyroid status and subclinical hypothyroidism.

Conclusion: Thyroid disease has a high prevalence among the study population which was comparable to findings of previous studies. Overt hypothyroidism was associated with adverse pregnancy outcomes. Further studies are required to assess thyroid status among Sri Lankan women, implications of thyroid status on pregnancy outcomes, plan strategies for screening, and interventions.