Assisted reproductive technology therapies such as in vitro fertilization are associated with the use of injectable fertility medications that are geared at producing a larger number of eggs. This in turn results in a greater likelihood of having multiple healthy embryos available for selection, which is a major reason that such therapies result in significantly higher pregnancy rates than other less aggressive treatments.
A rapidly growing therapeutic approach today involves the use of donor eggs for patients who have not been able to conceive using their own eggs, or in whom other factors may preclude them from being candidates for IVF, such as premature menopause or diminished ovarian reserve. In addition, as more women are delaying childbearing into their forties, the option of egg donation is commonly their primary treatment choice. Young donors, generally in their 20s or early 30s, undergo stimulation with injectable fertility medications, and the eggs are then retrieved for fertilization and transfer to the recipient patient or couple. Donors can be known (friend, younger relative, etc.), or anonymous (recruited by the fertility center and matched with the patient based on her choices), and since these donors are strictly screened in terms of their health and egg quality, most often the success rates of egg donation are the highest of all fertility therapies, as is the case here at our Center.
A concern that has arisen in the past is whether high responses to the fertility medications by these egg donors can in some way decrease the success rates of treatment; reflecting the cliché of “quantity not quality.” A study in the literature by Dr. Pena and colleagues from New York City addressed this very issue.
To begin with, the investigators evaluated over 300 fresh egg donor cycles and looked at the highest serum Estradiol level from the egg donors and grouped them into 3 levels; < 1500, 1500 – 3000, and > 3000 pg/ml. Their results revealed no significant differences in the quality of the eggs retrieved, or in the fertilization rates. In fact, higher peak Estradiol levels were directly correlated with a greater number of eggs retrieved, a greater number of embryos available, higher average embryo quality, and in the group with the highest Estradiol levels, higher embryo implantation rates. The authors concluded that such high Estradiol levels, reflecting higher donor responses, do not adversely affect the quality of the eggs or embryos, and on the contrary, are associated with improved implantation rates of these embryos.
Once again, the concern over whether “more is not better” in terms of egg donor responses has not been supported by the above, and other studies throughout the literature. This should help to reassure the rapidly growing number of patients who are now also experiencing the joy of parenthood through this wonderfully successful treatment process.