Donor eggs are used for two broad scenarios, lack of eggs or poor quality eggs.
Lack of eggs can be caused by early menopause or no response to ovarian stimulation for previous IVF treatment which has therefore been unsuccessful. Many women who do not respond to IVF drugs will be peri-menopausal and enter the menopause within the next five years or so.
Poor quality eggs may be the problem either because of a woman’s age or because she has not become pregnant after several IVF cycles and this can reduce the chance of success of conventional IVF.
The process of egg donation involves the following stages:
- The donor undergoes the steps of IVF stimulation up to and including egg collection.
- The eggs are then donated to the recipient couple and fertilised with the recipient partner’s sperm.
- The recipient woman also receives hormonal drugs to synchronise her ’cycle’ so that her uterus is at the right stage to receive the transferred embryo.
- Again counselling is essential, as the donor also has to be prepared for the medical risks of IVF.
In India about half of all donor egg cycles involve a close friend or family member as the egg donor. Pregnancy rates are similar to that of conventional IVF, but depend on the donor’s age rather than the age of the recipient.
Donor sperm is used where a man has no viable sperm and by single women or same sex couples, who often try self-insemination at home, turning to a clinic if this does not work. Donors may be recruited by fertility clinics or personally by the recipient. The process of sperm donation involves the following stages:
- The donors are screened for their family medical history and for diseases than can be transmitted through semen.
- Sperm is frozen and typically banked over several months for its future use.
- Three to six months later the screening tests are repeated, and the frozen sperm can be made available for use.
- Counselling is essential for both the recipient and donor, and covers the implications of being a donor or having children conceived in this way.
How donor sperm is used depends on the quality and quantity of the banked sperm, the age of the woman, and the presence of any other fertility factors. The simplest approach is IUI without ovarian stimulation, with insemination timed by blood tests. Adding mild ovarian stimulation increases the chance of pregnancy especially in older women. If sperm quality is lower, or the amount of sperm available is limited, or IUI has not worked, then the donor sperm can be used with IVF or even ICSI.
For younger women, the chance of pregnancy from simple IUI with donor sperm is about 20% per month, similar to that of fertile couples.