Interventions for subclinical hypothyroidism pre-pregnancy and during pregnancy

Treatment of women with normal thyroid function but positive peroxidase antibodies might possibly reduce preterm birth, but the evidence in insufficient.

Comment: The quality of evidence is downgraded by study quality (unclear allocation concealment, no blinding, incomplete outcome data, selective reporting) and by imprecise results.

Summary

A Cochrane review included 4 studies with a total of 362 subjects. In one trial of 115 women, levothyroxine therapy to treat pregnant euthyroid (normal thyroid function) women with thyroid peroxidase antibodies was not shown to reduce pre-eclampsia significantly (risk ratio (RR) 0.61; 95% confidence interval (CI) 0.11 to 3.48) but did significantly reduce preterm birth by 72% (RR 0.28; 95% CI 0.10 to 0.80). Two trials of 30 and 48 hypothyroid women respectively compared levothyroxine doses, but both trials reported only biochemical outcomes. A trial of 169 women compared the trace element selenomethionine (selenium) with placebo and no significant differences were seen for either pre-eclampsia (RR 1.44; 95% CI 0.25 to 8.38) or preterm birth (RR 0.96; 95% CI 0.20 to 4.61). None of the four trials reported on childhood neurodevelopmental delay.

Clinical comments

Date of latest search: 8 April 2013

Ədəbiyyat

1. Reid SM, Middleton P, Cossich MC et al. Interventions for clinical and subclinical hypothyroidism pre-pregnancy and during pregnancy. Cochrane Database Syst Rev 2013;(5):CD007752.