Endocrine Abstracts

In purpose to elucidate pathogenetic mechanisms of congenital forms of hypogonadotropic hypogonadism we have examined 25 women with idiopathic hypogonadotropic hypogonadism (IHH), mean age 26 years and 7 months (group 1). All patients had amenorrhea, little breast development (Tanner 2–3), absence or little axillery and pubic hair, infantile uterus and decreased ovary volume. There were no pathological changes during MRI-investigation. Twenty healthy women were included in control group (group 2).

Six patients had no significant difference in serum gonadotropins compared with control group (LH 4.7±2.4 U/l; FSH 5.2±1.2 U/l versus LH 5.43±0.57 U/l; FSH 5.63±0.31 U/l respectively). Peaks of LH and FSH every 10 min during 4 h were measured. There was a significant difference of basal LH and FSH concentration in patients with IHH and in the control group (LH 3.7±3.1 vs 6.9±3.1 P<0.05; FSH 5.2±1.8 vs 7.5±1.7 P<0.05). The significant decrease in the gonadotropin oscillations was found on the scattering diagrams comparing to the control group.

The genetic study showed polymorphism in gene of receptor to GnRH (Ser151Ser (AGC-AGT) and in β-subunit of FSH gene another polymorphism was found (Y76Y). These changes were previously described in literature and did not lead to the amino acid replacement.

The presence of antipituitary autoantibodies was detected in 8 (33.3%) patients with IHH and in 1 (5%) healthy woman (P<0.001).

Conclusions: 1) Patients with normal basal serum LH and FSH have it significantly lower oscillations, 2) polymorphisms found in these patients with IHH are not clinically important and 3) disorders of the humoral autoimmunity can be a reason of IHH.