Subclinical hypothyroidism among infertile women at a tertiary hospital in South-West Nigeria

Background: Overt thyroid dysfunction is an accepted cause of female infertility. Its milder form, subclinical hypothyroidism have also been implicated as a contributing factor to disturbed reproductive function. Objective: To determine the contribution of subclinical hypothyroidism (SCH) to the burden of infertility. Methodology: This is a cross sectional, comparative study of One hundred and twenty women with primary or secondaryin-fertility who presented for evaluation at gynaecological clinic and controls which are clients that came to access Family planning services. Results: The prevalence of infertility among gynaecological patients seen in the clinic was 38.8% (192/495). The prevalence of SCH among the studied infertile women was 11.7% (7/60) compared with 3.3% (2/60) of the control group (p=0.222).The commonest type of infertility was secondary, 76.7% (46/60). All thestudied infertile women with SCH presented with secondary infertility. There was an observed statistically significant difference in the mean serum TSH (3.19 +/- 4.38mIU /L vs 1.60 +/- 1.22mIU /L) and FT3, FT4 (0.29 +/- 0.074ng/dl vs 0.95 +/- 0.16ng/dl and 0.33 +/- 0.071ng/dl vs 1.09 +/- 0.19ng/dl respectively) Conclusion: Subclinical hypothyroidism was found to be higher among infertile women but this finding was not statistically significant, therefore, the routine screening for SCH among infertile women might be unnecessary