Premature ovarian failure or early ovarian insufficiency consists of the reduction or lack of oocytes (eggs) in patients under 40 years of age. Prevention of POF depends on the cause of the failure, although most times the cause is unknown and therefore it is not possible to prevent it.
The following are possible causes of POF and its prevention:
- Genetic causes
- the most frequent are alterations of the X chromosome. There are several possible alterations from numerical defects (monosomies, trisomies, mosaicism) to partial structural defects such as translocations and delections (e.g. Fragile X syndrome). There may also be alterations in autosomes (non-sexual chromosomes) such as translocations or alterations of a gene. In the case of early ovarian failure of genetic cause, prevention is not possible.
- Autoimmune causes
- It is estimated that autoimmune diseases are present in 15-30% of cases, whether endocrine or non-endocrine. Among the first we find: diabetes mellitus, hypothyroidism, hypoparathyroidism and hypophysitis. The non-endocrine ones include: chronic candidiasis, idiopathic thrombocytopenic purpura, vitiligo, alopecia, hemolytic anemia, pernicious anemia, systemic lupus erythematosus, rheumatoid arthritis, Crohn's disease, Sjögren's syndrome or chronic active hepatitis. Early diagnosis of these diseases and appropriate treatment can reduce the risk of premature ovarian failure.
- Metabolic causes
- These include galactosemia, the deficit of 17 α-hydroxylase /17.20 desmolase due to the CYP17 gene mutation, and the aromatase gene mutations. In these cases, proper diagnosis and treatment can minimize the risk of premature ovarian failure.
- 3-5% of patients with early ovarian failure have had a history of mumps, chickenpox infection, sigellosis or malaria. Recently, it has been suggested that HIV infection may lead to POF. Prevention of these diseases and vaccination where possible would be the appropriate behaviour to prevent ovarian failure.
- Toxic causes
- In patients who smoke, a reduction of the ovarian reserve has been observed and the age of natural menopause has been advanced by 1-3 years. Data on the influence of heavy metals, solvents, pesticides, plastics and industrial chemicals are inconclusive, although they have been implicated in endocrine or immunological disorders, DNA alterations, abnormal cell proliferation or inappropriate cell death.
- Medication causes (Yatrogeny)
- radiotherapy and chemotherapy have a gonadotoxic effect depending on the drug used, the dose and the age of the patient. Ovarian insufficiency may also arise as a consequence of the reduction of the functioning ovarian parenchyma, or of the surgical ischemia produced in the pelvic organs. Another possible cause of POF is the embolisation of the uterine artery, which is used for the treatment of different gynecological problems (e.g. myomas). In all these cases the recommendation would be to carry out a treatment of ovulation stimulation and vitrification of the oocytes obtained (fertility preservation) prior to the necessary treatment.
Although these causes are the most frequent, there are other factors that also influence POF. Women with epilepsy have a higher risk of early ovarian failure (up to 14%) so it is advisable to get reproductive advice to plan their genetic desire. The preservation of fertility through oocyte vitrification is recommended in these patients.