Who should consider using an egg donor?Any woman with a low probability of a successful normal pregnancy using her own eggs may be a candidate for IVF using an egg donor. The standard indication for donor eggs is poor egg quality or lack of eggs (menopause). Since the uterus generally remains functional despite poor egg quality, substituting donor eggs can restore an opportunity for pregnancy.
Egg donors for older womenAn advanced reproductive age is probably the most common reason for IVF using an egg donor. Under natural conditions, a woman gradually loses her fertility potential, although a number of studies suggest that the loss of fertility accelerates after age 37 to 38 (see data below).
By age 40 to 44, a woman’s fertility is only about 5 percent of the peak fertility at age 20-24 years. Combined with tests for ovarian reserve, the success rate from using donor eggs usually exceeds the success rate for using a woman’s own eggs and certainly for any woman over 38 to 40. Nevertheless, success rates are not the only determination for undergoing treatment and many women try at least once with their own eggs before opting for donor eggs.
The role of ovarian reservePoor ovarian reserve refers to poor fertility potential. Poor ovarian reserve is closely linked to advancing reproductive age. However, some younger women also demonstrate evidence of poor fertility and a low likelihood for success with their own eggs.
Doctors diagnose poor ovarian reserve on the basis of a combination of a history of low egg production in prior IVF cycles, measuring small ovarian volumes or few antral follicles on ultrasound, elevated levels of estrogen in the early follicular phase, and elevated follicular stimulation hormone (FSH) levels in the early follicular phase or in response to clomiphene stimulation (CCT).
Early menopause, genetic factorsPremature ovarian failure (POF) refers to early menopause which could be considered the most severe form of poor ovarian reserve. The normal age for menopause is 51 but traditionally we diagnose POF when menopause arrives before age 40. We generally reserve this term for women who have the hallmarks of menopause: lack of menstruation and elevated FSH levels with or without other symptoms such as hot flushes.
Occasionally, a woman will have genetic disorder that either results in POF, recurrent miscarriages or a high probability of genetic disease in any children. In such situations, using a donor egg alleviates the risk of an affected child and corrects the POF induced by the genetic abnormality.
The X chromosome carries genes necessary for egg production. Women who have a single X chromosome (Turners syndrome) or an abnormal X chromosome have POF at varying ages.
Use of donated eggs – which doctors refer to as " donor egg IVF – provides these women with an opportunity to become pregnant. Turners Syndrome patients may have complicated pregnancies and should seek counseling with a maternal fetal medicine specialist before treatment.
Women with a balanced translocation produce a very high proportion of abnormal eggs and embryos. Some of the translocations lend themselves to preimplantation genetic diagnosis (see PGD section for details), and fertility doctors can identify the few normal embryos for transfer thus avoiding additional miscarriages.
However, some translocations cannot be treated with PGD because the genetics team cannot obtain genetic probes. Some women produce only abnormal embryos and doctors cannot use PGD to obtain a normal pregnancy. Donor eggs are useful in these cases as well.
Another rare genetic disorder includes those women who carry mutations in the DNA located in the mitochondria (the part of the cell that produces energy). A person receives all their mitochondria from their mother, thus if the mother carries a genetic defect in the mitochondria, the child could have a metabolic disease. The genetics of these disorders are complex and varied, so careful genetic counseling is necessary before making any decision. PGD may also be possible for this disorder in the near future. Donor egg IVF provides one treatment alternative.
The steps of IVF with an egg donorA donor egg cycle is slightly different than a conventional IVF cycle. See more detail in Working With an Egg Donor.
- The patients and physician decide that donor eggs are the best treatment option.
- The patient (the recipient of the egg donation) begins by selecting potential egg donors. The NCRS staff and potentially an egg donor agency work with the patient to match with an egg donor.
- The patient and donor’s menstrual cycles are synchronized.
- The donor begins IVF stimulation and monitoring leading to egg retrieval.
- The recipient begins hormone replacement for controlled endometrial development (CED).
- A fertility doctor retrieves the donor eggs, and laboratory staff combine them with sperm from the recipient’s partner or donor sperm to allow embryo formation.
- The embryo transfer issues are similar to conventional IVF except that with a much higher success rate (implantation rate per embryo), we must be careful to limit the number of embryos transferred.
- The recipient does not make any of her own hormones in a CED cycle, consequently, she must continue the hormone replacement rigorously until 10 weeks of pregnancy, by which time the pregnancy produces its own hormones.