High frequency of antithyroid autoantibodies in pregnant women at increased risk of gestational diabetes mellitus

Abstract

Background: Thyroid autoantibodies (ThyAb) and subclinical hypothyroidism occur more frequently in pregnant women with insulin-dependent diabetes mellitus than in healthy pregnant women. Few studies have investigated the presence of ThyAb in women with gestational diabetes mellitus (GDM), and no significant association between diabetes in pregnancy and thyroid function has been reported. Objective: To assess the thyroid biochemical profile and estimate the prevalence of ThyAb in a group of pregnant women at increased risk of GDM due to family and personal risk factors, and to investigate the relationship between a positive family history of diabetes or thyroid diseases and the eventual presence of ThyAb during pregnancy. Methods: Oral glucose tolerance, serum ThyAb and thyroid function were evaluated in 181 pregnant women with increased risk for GDM (study group). Seventeen healthy pregnant women without risk factors for GDM and with a normal glucose tolerance were recruited as controls. Results: The women who developed GDM showed a mean free thyroxine concentration significantly lower than that observed in the healthy pregnant women and in those with impaired gestational glucose tolerance and normal glucose tolerance. Twenty-nine of the 181 women in the study group (16%) were ThyAb positive. However, the risk of being ThyAb positive during pregnancy was three times greater in the women with positive family history of both diabetes mellitus and thyroid disease than in those with no family history of these conditions. Conclusions: This study showed that women with increased risk of GDM, mostly those with family history of diabetes mellitus and thyroid disease, also have an increased risk of being ThyAb positive during pregnancy. It also highlighted the importance of evaluating thyroid function in pregnant women with impaired glucose tolerance, in view of their increased risk of subclinical hypothyroidism.

Risk factors for congenital hypothyroidism: results of a population case-control study (1997–2003)

“…The same authors suggested that if adequate control of the maternal diabetic condition is achieved, the alterations in foetal thyroid hormone economy would be avoided. Moreover, in a previous study (30), we reported an increased risk of subclinical hypothyroidism during pregnancy in a group of women with gestational diabetes. Taken together, all these findings highlight the importance of an adequate metabolic control during pregnancy in order to reduce maternal and foetal morbidity, including transient and permanent forms of neonatal hypothyroidism.…”

The Association Between Depression and Diabetes in the Perinatal Period

“…Another hypothesized connection between diabetes and depression in the perinatal period is thyroid function. In one study, pregnant women who developed GDM had a mean free thyroxine concentration (measured ∼ 28 weeks) significantly lower than that observed in healthy pregnant women [22]. Another study found antenatal measurements of total thyroxine and free thyroxine to be negatively and significantly correlated with mean depression scores at three postpartum periods [23].…”

Subclinical Hypothyroidism in Pregnancy - A Case Series

“…Feely et al documented that SCH coexisted in 30% cases of GDM 55 . Many other literatures have also documented an association of thyroid abnormalities, notably overt and subclinical hypothyroidism as well as autoimmune thyroiditis with GDM [56][57][58][59][60] . This correlation has been substantiated by depiction of an inverse association between Metforfin and TSH level 61,62,63 .…”