Perinatal factors in the aetiology of hypopituitarism.

The possible aetiological factors were studied in 73 children with idiopathic growth hormone deficiency. The following perinatal abnormalities were found to be more frequent than expected: breech presentation (32.9%) and asphyxia (15.0%). Parallel with an increased application of caesarean section there was a significant reduction in the incidence of breech birth among the hypopituitary patients. On the basis of TSH levels measured during TRH tests, most of the patients with breech delivery had a hypothalamic damage, while at vertex position the pituitary damage was more frequent. Of the two pairs of siblings with hypopituitarism both members of the first had breech birth and of the second high birth weight. It is concluded that perinatal abnormalities are important aetiological factors in hypopituitarism and that the occurrence of this disease can be reduced with improved obstetrical practice and perinatal care.