Universal screening versus selective case-based screening for thyroid disorders in pregnancy.

Thyroid dysfunction in pregnancy is associated with significant maternal, fetal, and neonatal complications. Early treatment of thyroid disorders can effectively reduce the risk of such complications. The results of different clinical trials have demonstrated that screening pregnant women for thyroid dysfunctions is cost-effective and should be encouraged. However, there is no consensus over the advantages of universal versus case-finding screening for thyroid disorders during pregnancy. A systematic review was performed by searching PubMed, Scopus, and Web of Science databases for studies having been carried out to make a comparison between universal and case-finding screening methods during pregnancy in terms of the loss rate. The main search criteria were related to thyroid function, pregnancy, and adverse outcomes. All articles in English language are included. We analyzed by random effect method due to between-study heterogeneity. Among 241 articles found using the search terms, 40 articles were included out of which 10 were considered as acceptable and relevant. Five articles showed that case-finding screening missed between 30 and 55% of pregnant women with thyroid dysfunction. 4 studies demonstrated that universal screening and detection of thyroid dysfunction may lead to less miscarriage and pregnancy complications. The results of 2 studies demonstrated that universal screening in pregnancy with a focus on hypothyroidism would be cost-effective. Early detection of thyroid dysfunction in pregnancy can minimize the adverse maternal and fetal outcomes and is demonstrated to be cost-effective. Meta-analysis confirmed that case-based screening may miss up to 49% of pregnant women with thyroid dysfunction. This provides further support for the argument in favor of universal screening of thyroid disorders in pregnancy. In order to shed more light on the advantages of universal screening for thyroid disorders in pregnancy, more comprehensive randomized controlled trials with larger cohorts are required.