A 28-year-old gravida III, with a history of two unsuccessful pregnancies, was admitted with hyperemesis gravidarum and was found to be suffering from hyperparathyroidism (HPT). She was treated surgically and was later delivered of a wellformed, premature girl. The literature is reviewed and the histories of 40 females (including the patient of this case report) with a minimum of 93 pregnancies while suffering from HPT shows, that HPT during pregnancy is a serious condition for the fetus as well as for the mother. There was an increased incidence of spontaneous abortion, perinatal death, premature birth and neonatal morbidity. The mothers suffered from increased episodes of renal calculi and hyperemesis gravidarum. The exacerbations nearly always occurred in the first and second trimesters or post partum.