Nausea, vomiting and thyroid function before and after induced abortion in normal pregnancy.

Thyroid function in early pregnancy has been reported to be slightly different from that in second or third trimester. We assessed thyroid function before and after induced abortion in normal pregnant women. A significant increase in serum Free T4 and a decrease in serum TSH were observed before abortion and these changes, apart from the contemporary significance of serum hCG-beta, were especially marked in pregnant women with nausea and vomiting. On the other hand, an increased level of Free T4 and a reduced level of TSH returned to the normal ranges 7-10 days after induced abortion. Furthermore, serum hCG-beta was significantly reduced. These results suggest that, in normal early pregnancy, thyroid function may be related to serum hCG-beta concentration and its increased level, which induces gestational emesis.