Aetiology and Clinical Characteristics of Primary Amenorrhoea with Hypothalamic or Pituitary Disorders at a...

To identify the causes and clinical characteristics of women with primary amenorrhoea and hypothalamic or pituitary gland disorders.

This retrospective study was conducted at a quaternary hospital in southern Thailand. The medical records of women diagnosed with primary amenorrhea and hypothalamic or pituitary gland disorders (hypogonadotropic hypogonadism [HH]) were reviewed. HH was defined as an oestradiol level of < 20 pg/mL, decreased (< 5 mIU/mL) or normal serum follicle-stimulating hormone (FSH) levels, and no organic disease of the uterus or ovaries.

Fifty-five women with HH were included. The median (interquartile range [IQR]) age at presentation was 18 years (range, 17-20 years). Most patients presented with primary amenorrhoea (50/55), followed by primary infertility (3/55). All women had low levels of oestradiol (5 pg/mL [5.0-12.1]), FSH (0.8 mIU/mL [0.3-3.7]), and luteinising hormone (0.5 mIU/mL [0.1-2.3]). The most common cause was hypothalamic dysfunction (80%); including congenital hypogonadotropic hypogonadism (CHH) (43.6%), constitutional delay of growth and puberty (CDGP) (14.5%), and functional hypogonadotropic hypogonadism (FHH) (10.9%). Regarding hypothalamic dysfunction, patients with CHH were significantly older than those with CDGP (20 years [17.0-26.5] vs. 16.5 years [15.8-17.2]; P = 0.014) and had significantly lower FSH levels compared to those with FHH (0.6 mIU/mL [0.3-1.0] vs. 4.5 mIU/mL [2.8-5.7]; P = 0.026).

Hypothalamic dysfunction, particularly CHH, is the most common cause of primary amenorrhoea and HH.