Clinical characteristics and thyroid function in complete hydatidiform mole complicated by hyperthyroidism

In women with complete hydatidiform mole (CHM), a greater risk of hyperthyroidism and its complications was observed in relation to factors such as uterine fundal height > 16 cm, uterine fundal height > gestational age (GA), theca lutein cysts >6 cm, and hCG >400,000 IU/L at presentation. Close monitoring of thyroid function during postmolar follow-up demonstrated that, as thyroid hormones are normalized within 2–3 weeks post-evacuation, treatment with beta-blockers or antithyroid drugs can be rapidly discontinued.

• In this observational study of women with CHM, possible clinical factors related to hyperthyroidism at presentation and post-evacuation thyroid function were investigated.

• A total of 137 CHM patients were included, of whom 69 (50.3%) had hyperthyroidism of any type (43.5% subclinical, 56.5% overt) at presentation.

• Factors significantly linked with both subclinical and overt hyperthyroidism were: uterine fundal height > 16 cm or > GA, and theca lutein cysts >6 cm.

• For hyperthyroidism prediction, the identified optimal hCG cutoff was 430,559 IU/L (sensitivity 85.5%, specificity 83.8%).

• Of women with hyperthyroidism at presentation, 13% had post-evacuation hyperthyroidism/transient hypothyroidism conversion.

• In participants not demonstrating conversion to hypothyroidism, median time for TSH normalization was 2 and 3 weeks for subclinical and overt hyperthyroidism, respectively.

• Normalization of fT4 was noted at 2 weeks in women with overt hyperthyroidism.