Abstract
Varying degrees of hyperthyroidism have been found in 30% to 60% of women with hyperemesis gravidarum. The spectrum of clinical indicators ranges from subclinical hyperthyroidism, where there is an isolation of biochemical evidence of low TSH and mildly elevated serum T4 concentration levels, to clinical hyperthyroidism (gestational thyrotoxicosis). In rare cases, manifestations as severe as thyroid storm may occur. The purpose of the current study is to explore the association between hyperthyroidism and hyperemesis gravidarum in Saudi women. To achieve this objective, 100 pregnant women at 6-13 weeks of gestation were divided into two groups of 50 women each. First group (control): women with normal pregnancies who experienced emesis and were treated in the outpatient clinic. The second group (case): women with severe repeated vomiting who required hospital admission (hyperemesis gravidarum). None of the women had been diagnosed with hormonal dysfunction before pregnancy. However, analysis of thyroid functions found elevated serum FT3 and FT4 levels in a significant number of women with hyperemesis compared to the control group (26% vs 2%) and (44% vs 6%) respectively. Likewise, a significant number of women (72%) in the case group showed lower than normal mean TSH levels compared to only 6% of those in the control group. Hyperthyroidism was clearly detected in the present study, but it did not reach levels requiring antithyroid medication. This suggests that the biochemically altered thyroid function found in women who are clinically euthyroid may be responsible for their hyperemesis and may be one reason that the condition continues into the second trimester.