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F O R P H Y S I C I A N S – resources
Transition from OI/IVF to Donor Oocytes
Introduction
Since the first successful in vitro fertilization cycle was reported in 1978, efforts have been directed toward increasing the chance of success with the procedure. This first pregnancy was accomplished in a normal, unstimulated menstrual cycle. As time passed, it was recognized that stimulation of the ovaries in order to achieve the development of several mature follicles would increase the chance of retrieving one or more mature oocytes. Initially, clomiphene citrate was used, followed shortly thereafter by administration of gonadotropins. Reports were published showing that the chance of pregnancy could be enhanced by the transfer of more than one embryo, leading to higher pregnancy rates, but at the expense of higher multiple pregnancy rates. With the advent of GnRH agonists, pituitary down regulation permitted ovarian stimulation without the risk of an LH surge, a major reason for cycle cancellation in the early days of IVF.
As data accumulated, it became evident that the chance of pregnancy per embryo transferred was highly dependent upon the woman's age, and that a higher number of embryos could be transferred to the uterus of an older woman without increasing the risk of multiple pregnancy as much as in younger women. Despite this practice, however, the chance of successful pregnancy in older women remained low and the chance of live birth even lower. It was also recognized that many younger women had IVF cycles with characteristics similar to their older counterparts. These included poor response to ovarian stimulation, low number of oocytes retrieved, poor oocyte quality, poor embryo quality, poor implantation rates, and high spontaneous abortion rates. These findings were felt to be secondary to poor oocyte quality, as in the older women. Proof that an abnormality of oocyte quality rather than of uterine receptivity is the underlying cause for the poor results of IVF in older women came with the first reports of donor oocyte IVF, with the chance of successful pregnancy being related to the age of the donor and unrelated to the age of the recipient. This has been born out by many studies as well as the clinical experience of IVF programs throughout the world.
In many women undergoing IVF for reasons such as unexplained infertility, tubal occlusion, pelvic adhesions, endometriosis, and semen abnormalities, poor oocyte quality is suspected to be a significant problem, either before the cycle or because of the findings during the IVF cycle. In order to enhance the chance of success as well as to avoid performing an expensive IVF cycle for a woman in whom failure could be predicted, it would be optimal to be able to assess the quality of oocytes before committing resources to IVF. Unfortunately, that assessment is less than perfect and we often consider oocyte donation only after the failure of traditional IVF to result in a live birth.
When POF occurs, it has been shown that there may be some ovarian follicles remaining, menses may return, and pregnancies may occur. The two primary concerns of the woman and the clinician include the woman's fertility potential and the long-term consequences of hypoestrogenemia. This lecture will present the currently understood causes of POF, a reasonable diagnostic approach to the problem, the long-term health consequences of POF, and therapeutic considerations.
Selection Of Couples For Donor Oocyte IVF
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Ovarian failure
Oophorectomy
Genetic disorders
Advanced age
Poor oocyte quality
Failed IVF
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Suggested Reading
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