Primary Ovarian Insufficiency can be categorised into two main types:
1. Sporadic POI: This is the most common type and occurs unpredictably. The ovaries stop functioning normally without any clear reason.
2. Familial POI: In some cases, there’s a family history of POI, indicating a genetic component. This type might have a hereditary link and could affect multiple generations within a family.
POI can also be classified based on clinical findings and serum FSH levels:
- Occult primary ovarian insufficiency: This is characterized by unexplained infertility and a normal basal serum FSH level.
POI can be caused by genetic disorders, such as Fragile X syndrome and Turner syndrome. It can also be caused by a low number of follicles.
A medical triad for the diagnosis of POI is amenorrhea, hypergonadotropism, and hypoestrogenism.
People with POI can have irregular or occasional periods for years, and they might even get pregnant. Treatment can restore estrogen levels in people with POI.