Thyroid disease symptoms during early pregnancy do not identify women with thyroid hypofunction that should be treated

Abstract

This study does not support the ATA recommendation that pregnant women who require levothyroxine therapy can be identified by case-based screening of women with symptoms of thyroid disease.

Maternal cognitive function during pregnancy in relation to hypo‐ and hyperthyroxinemia

“…17 Also, the thyroid parameters are similar to that of another large population pregnant sample of the Generation R study, as discussed in detail elsewhere. 17 Also, the thyroid parameters are similar to that of another large population pregnant sample of the Generation R study, as discussed in detail elsewhere.…”

“…Several clinical and sociodemographic characteristics of women included in the current study are similar to that of the Dutch national perinatal obstetric data, including age, parity and previous abortion as discussed elsewhere. 17 Also, the thyroid parameters are similar to that of another large population pregnant sample of the Generation R study, as discussed in detail elsewhere. 17 The current sample was higher educated compared with the national standard and almost all women were Caucasian, compared with the national figure of 80%.…”

“…36 An alternative could be to assess thyroglobulin as a reflection of long-term iodine intake but TG is susceptible to physiological changes during pregnancy and the presence of Tg-Ab. 17 This suggests that hypothyroxinemia is probably related to the 'massive foetal consumption' of transplacentair transported T4 during gestation. The most prominent cause of hypothyroxinemia is low iodine intake.…”

“…15 The exact origin of gestational hypothyroxinemia in iodine sufficient areas is unknown but is thought to be explained by the 'massive foetal consumption' of trans-placental transported T4 during gestation and the substantial de-iodination of T4 by the placenta. 17 However, we did not correct for hypo-and hyperthyroxinemia in the 'euthyroid' group nor for TPO-Ab status. For example, we recently reported that at 12 weeks of gestation, there were no differences in thyroid dysfunction symptoms between women with (sub)clinical thyroid dysfunction when compared to euthyroid women.…”

“…For example, we recently reported that at 12 weeks of gestation, there were no differences in thyroid dysfunction symptoms between women with (sub)clinical thyroid dysfunction when compared to euthyroid women. 17 However, we did not correct for hypo-and hyperthyroxinemia in the 'euthyroid' group nor for TPO-Ab status. Many other studies (summarized elsewhere) did also not correct for hypothyroxinemia in the 'euthyroid' control group.…”