Serum levels of the road stimulating hormone (TSH) triiodothyronin(T3), tetraiodothyronin(T4), progesterone(P) and Zinc were measured for 25 women presenting to the antenatal clinic is Sohag University hospital with emesis gravidarum during the first or early second trimester of pregnancy. The same was done for 25 healthy pregnant women presenting for routine antenatal care to serve as controls, women in both groups were subjected to adequate history taking as well as clinical examination. Women with emesis gravidarum were siginficantly younger and of lower parity than controls... The mean . . . . . serum TSH and T4 were significantly lower amongst the emesis group Serum T4 and P were significantly higher, however serum T3 and Zn concentrations were slightly but insignificantly higher compared to controls. In conclusion, thyroid dysfunction and placental overactivity may play a role in the causation of emesis gravidarum.