The major cause of neonatal mortality and morbidity is preterm delivery in general (< 37 completed weeks), and especially very preterm delivery (< 32 completed weeks). The objective of this study is to determine if either thyroid hormonal dysfunction and/or the presence of thyroid autoantibodies in the mother are associated with an increased risk of preterm and/or very preterm delivery. Data were collected prospectively and analyzed as a nested-case control study. There were 953 delivered gravidas enrolled between 1996 and 2002. Samples were collected at entry to care and stored at -70°C. Cases included all women with preterm delivery (n = 124). Controls (n = 124) were randomly selected from among the 829 women who delivered at term (> 37 completed weeks). All samples were assessed for thyroid stimulating hormone, thyroperoxidase antibody, and thyroglobulin antibody. Gravidas with high thyrotropin (TSH) levels had a greater than threefold increase in risk of very preterm delivery. In some analyses, gravidas who tested positive for thyroglobulin antibody at entry to prenatal care also had a better than twofold increased risk of very preterm delivery. There were no significant associations between TSH level or thyroglobulin antibody positivity and the risk of moderately preterm delivery.
All Science Journal Classification (ASJC) codes
- Endocrinology, Diabetes and Metabolism