This is #17 in a series of answers to common questions about failed IVF.
For women whose advancing age and/or ovarian resistance make having a baby with their own eggs unfeasible or unlikely, IVF using donated eggs from a young donor (under 35 years) is an excellent option and is statistically highly successful – with approximately 60% conceiving following embryo transfer. The main reason why IVF with egg donation is so highly successful resides in the improved number and quality of a younger woman’s eggs:
- Younger women usually have a healthy ovarian reserve and are thus capable of yielding numerous eggs at the time of egg retrieval (ER).
- Since age is the major determinant of egg chromosomal integrity (the rate limiting factor in human reproduction), the eggs of younger women are far more likely to be “competent,” meaning that upon fertilization, they are capable of propagating chromosomally normal (“competent”) embryos. Such embryos are the ones that are most likely to develop into normal, healthy babies.
Women choosing to undergo egg donation understandably have high expectations of a successful outcome, and when they fail to conceive, they are often bewildered, angry and feel betrayed. But there are explanations as to why IVF with egg donation can and does fail.
- Even younger women can have diminished ovarian reserve that goes undetected. In other cases, in spite of best effort on the part of the treating medical team, an egg donor will have a low yield of eggs.
- Less than half the eggs of younger women are euploid (have a normal number of chromosomes) and abnormal (“aneuploid”) eggs cannot develop into competent embryos.
- The eggs derived from very young donors (in their late teens or early 20’s) are often of poorer quality and may produce more “incompetent” embryos. That is why, in my opinion, the ideal age of an egg donor is between 26 and 35 years.
- In addition, very young donors are much more prone to ovarian hyperstimulation on fertility drugs. In such cases, egg quality can also be compromised.
- On the other side of the equation, there is the reality that some embryo recipients may have embryo implantation dysfunction(usually undiagnosed). This can be due to:o Inadequate endometrial (uterine lining) thickness(more common in post menopausal women who have had prolonged estrogen deprivation).o Previously undetected/unaddressed uterine surface lesions that interfere with implantation (submucous fibroids, scar tissue or polyps)o Immunologic implantation dysfunction which often goes unsuspected, undetected, undiagnosed and untreated.
- Hitherto unrecognized male factor infertility.
Unless such issues are addressed, even the transfer of the very best quality donor embryos will often not propagate viable pregnancies.
The answer (as always) lies in the fact that each egg donation candidate and her partner must be thoroughly evaluated before embarking on a cycle of IVF with donated eggs, and each egg donor must be carefully selected and evaluated for ovarian reserve.
In my opinion, the ideal egg donor is 26-34 years of age, has regular ovulatory cycles, has had no prior difficulty in achieving pregnancy and (ideally) will in the past have successfully donated eggs which propagated one or more viable pregnancies. True, it is rare to find all these attributes in most egg donors, but knowing the “best case” criteria can help a couple more effectively evaluate their donor choices and optimize their chances of IVF success.