Subclinical hypothyroidism affects 4–8.5% of the general population and an even greater percentage of patients with infertility. Untreated subclinical hypothyroidism has been associated with adverse pregnancy outcomes, however, it is less clear if subclinical hypothyroidism affects fertility. The goal of this study was to investigate whether levothyroxine treatment has beneficial effects on IVF and pregnancy outcomes in infertile patients with subclinical hypothyroidism.METHODS:
An IRB approved retrospective chart review of patients undergoing IVF cycles between January 1, 2010 and December 31, 2013. Patients were included if they were between 25 and 45 years old and had an ICD9 diagnosis of subclinical hypothyroidism. Patients were divided into two groups: TSH less than/equal to 2.5 (Group 1, N=63) and TSH greater than/equal to 2.5 (Group 2, N=58). An analysis was performed to determine if there was a difference in mean number of embryos retrieved, clinical pregnancy rate, or live birth rate or between the groups.RESULTS:
No difference was found in mean number of oocytes retrieved, clinical pregnancy, or live birth rate. There was a trend toward higher pregnancy rate in the untreated group.CONCLUSION:
This study does not demonstrate a difference in number of oocytes retrieved, clinical pregnancy rate or live birth rate between patients with treated versus untreated subclinical hypothyroidism undergoing fresh IVF cycles. There was a trend toward higher pregnancy rate in the untreated group. This analysis is unique as it compares IVF/pregnancy outcomes between adequately treated and untreated subclinical hypothyroid patients, whereas previous studies have used euthyroid patients as a control.