Many women have none of these issues, but continue to be unsuccessful using their own eggs—in other words, they have undiagnosed infertility—and thus turn to donor eggs or donor embryos. As stated above, egg donation is also helpful for gay male couples using surrogacy (see LGBT parenting). In the US and UK, if desired (and if the egg donor agrees), the couple can meet and get acquainted with the egg donor, her children and family members. More often, egg donations are anonymous or semi-anonymous (i.e. the egg donor may provide personal and medical information, photographs of herself and/or family members, and an email or third party willing to convey communications between the donor and recipients). In some countries, the law requires non-anonymity (e.g., the UK). In other countries, the law requires anonymity (e.g., France, Spain, the Czech Republic, South Africa). In the US the choice between anonymity, semi-anonymity and non-anonymity is made by the donor and recipient, although some IVF clinics that maintain their own databases of egg donors strongly encourage or require anonymity. Congenital absence of eggs
Turner syndrome
Gonadal dysgenesis
Acquired reduced egg quantity / quality
Oophorectomy
Premature menopause
Chemotherapy
Radiation therapy
Autoimmunity
Advanced maternal age
Compromised ovarian reserve
Other
Diseases of X-Sex linkage
Repetitive fertilization or pregnancy failure
Ovaries inaccessible for egg retrieval

Types of donors
Donors includes the following types:

Donors unrelated to the recipients who do it for altruistic and/or monetary reasons. In the US they are anonymous donors or semi-anonymous donors recruited by egg donor agencies or IVF clinics. Such donors may also be non-anonymous donors, i.e., they may exchange identifying and contact information with the recipients.
Throughout the cycle the donor is monitored often by a physician using blood tests and ultrasound exams to determine the donors reaction to the hormones and the progress of follicle growth. Once the doctor decides the follicles are mature, they will establish the date and time for the egg retrieval procedure. Approximately 36 hours before retrieval, the donor must administer one last injection of HCG hormone to ensure that her eggs are ready to be harvested. The egg retrieval itself is a minimally invasive surgical procedure lasting 20–30 minutes, performed under sedation by an anaesthetist, to ensure the donor is kept completely pain free. Egg donors may also be advised to take a pain-relieving medicine one hour before egg collection, to ensure minimum discomfort after the procedure. A small ultrasound-guided needle is inserted through the vagina to aspirate the follicles in both ovaries, which extracts the eggs. After resting in a recovery room for an hour or two, the donor is released. Most donors resume regular activities by the next day. Results
In the United States, egg donor cycles have a success rate of over 60%. (See statistics at http://www.sart.org.) When a "fresh cycle" is followed by a "frozen cycle", the success rate with donor eggs is approximately 80%. With egg donation, women who are past their reproductive years or menopause can still become pregnant.