Serum levels of TSH, T3, T4, progestrone and zinc were mesured for 25 women presenting to the Antenatal Clinic of Sohag University Hospital with emesis gravidarum during their first or early second trimesters of pregnancy. The same parameters were measured for 25 healthy pregnant women as control. Women with emesis gravidarium were significantly younger and of lower parity than the control. Serum TSH leve was significantly lower amongest the group of emesis gravidarum, but serum levels of T4 and progestrone was higher. Also, there is no significane differenc in T3 and zinc concentration. In conclusion, thyroid dysfunction as well as placental hyperactivity as evidenced by increased progestrone level may play a role in the causation of emesis gravidarum.