Thyroid function in hyperemesis gravidarum.

Twenty-five patients with severe persistent vomiting were studied. On admission they were given the diagnosis of hyperemesis gravidarum. Hyperemesis was defined as vomiting of sufficient severity to warrant admission to hospital and iv therapy, which was not associated with any other condition known to cause vomiting other than the pregnancy itself. Ten (40%) of the patients had free thyroxine levels which were elevated on admission with hyperemesis. The free thyroxine normalised when the patients were well but still pregnant and remained normal post partum. Longitudinal data for nine other thyroid parameters are given and all illustrate the transient nature of the disturbed function in hyperemesis gravidarum.