This study focuses on the phenotyping and genotyping of women with hypergonadotropic ovarian dysfunction (WHO III status).

First goal of the study is to phenotype patiens with hypergonadotropic ovarian dysfunction (WHO III) adequately. This group includes women with premature ovarian failure (POF), incipient ovarian failure (IOF), poor response after ovarian hyperstimulation, early menopause and hypergonadotropic primary amenorrhea. The standardized phenotyping consists of a questionnaire focusing on reproductive, medical, and family history; ultrasonography to assess ovarian reserve and/or antral follicle count and obtaining an extra blood sampling during routine endocrine screening for genotyping.

Phenotyping of patients presenting with ovarian dysfunction is of crucial importance when genotyping will be performed. The goal of this genotyping will be the identification of genetic factors associated with the (premature) depletion of the stock of ovarian follicles. It will be performed for isolated WHO III patients in an association (case-control) study for known candidate genes. In familial WHO III cases, genome wide linkage analysis will be performed.

Inclusion Criteria:

• POF; defined as secondary amenorrhea before 40 years of age and basal FSH > 40 IU/L
• Incipient ovarian failure; defined as normo-ovulatory cycles, raised basal FSH > 12 IU/L
• Poor response patients; defined as less than 4 oocytes retrieved or cancellation in case of absent follicle growth after ovarian hyperstimulation with 300 IU gonadotropins or cancellation in case of absent follicle growth
• Women with early menopause (between 40-45 years)
• Hypergonadotropic primary amenorrhea

Exclusion Criteria:

• Primary amenorrhea with early development disorders causing absence of ovaries and Swyer syndrome (XY)

Women with WHO III status who attend the outpatient clinic of participating hospitals.