Levothyroxine in Women with Thyroid Peroxidase Antibodies before Conception

This double blind, placebo controlled trial investigated whether levothyroxine treatment could increase live birth rates among euthyroid women with thyroid peroxidase antibodies and a history of miscarriage or infertility. A total of 952 women were randomly assigned to receive either 50 µg of levothyroxine or placebo daily before conception through the end of pregnancy. The primary outcome was live birth after at least 34 weeks of gestation. Results showed no significant difference in live birth rates between the levothyroxine group (37.4%) and the placebo group (37.9%) (relative risk, 0.97; 95% CI, 0.83 to 1.14; P=0.74). There were also no significant differences in other pregnancy or neonatal outcomes. The study concluded that levothyroxine did not improve live-birth rates in this population.

This double blind, placebo controlled trial investigated whether levothyroxine treatment could increase live birth rates among euthyroid women with thyroid peroxidase antibodies and a history of miscarriage or infertility. A total of 952 women were randomly assigned to receive either 50 µg of levothyroxine or placebo daily before conception through the end of pregnancy. The primary outcome was live birth after at least 34 weeks of gestation. Results showed no significant difference in live birth rates between the levothyroxine group (37.4%) and the placebo group (37.9%) (relative risk, 0.97; 95% CI, 0.83 to 1.14; P=0.74). There were also no significant differences in other pregnancy or neonatal outcomes. The study concluded that levothyroxine did not improve live-birth rates in this population.