Interview With Dr. Colver
Question: Dr. Colver, so many of us are new to egg donor issues and are anxious to know more about this exciting new medical technology. Can you explain a little about it now?
DR. COLVER: Donor egg was first reported in 1983. Oocyte donation may be the only treatment option for patients with a number of disorders. Patients with ovarian failure comprise the largest group of women presenting for oocyte donation. These are patients who have loss of ovarian function due to premature ovarian failure, chemotherapy, or pelvic radiation for treatment of malignancies, surgical removal of the ovaries, and auto-immune disorders. Patients with heritable autosomal dominant or X linked recessive disorders would be indicated in order to obviate the risk of transmission to the offspring.
The most common group of patients presenting for oocyte donation are those with diminished ovarian function. This would include patients who have had repeatedly failed assisted reproductive technology (ART) procedure due to persistently poor oocyte and/or embryo quality, and those patients of advanced maternal age, particularly over 40 years old.
Women who are interested in becoming egg donors may be recruited through advertisements in local newspapers, magazines, or by word of mouth. In most clinics these are patients who are under 35 years of age who are in good health with normal ovarian function.
The donors undergo a complete history and physical examination, detailed review of genetic and infectious disease history, psychological evaluation, and extensive counseling regarding the risks inherent with the procedure. The donor is screened for infectious diseases, including HIV, syphilis, hepatitis and chlamydia.
The donor then takes fertility medications, Lupron and Fertinex, in order to achieve controlled ovarian hyperstimulation. She is monitored with serial ultrasonographic evaluations and estradiol levels until adequate follicular development is achieved. Then the patient is administered human chorionic gonadotropin (hCG) and an oocyte retrieval is performed 36 hours later.
Prior to retrieval of the oocytes, the recipient's endometrium is being prepared by taking estrogen and then estrogen in combination with progesterone. These medications are administered so that once the embryos have developed the endometrium will be receptive and hopefully implantation of the embryos will occur.
The embryo transfer may be performed by placement of the embryos into the uterus or into the fallopian tubes. In some centers, a zygote may be transferred into the fallopian tube. A zygote is a fertilized egg that has not divided. A zygote transfer would occur the day after the oocyte retrieval, and an embryo transfer into the uterus would occur three days after the retrieval.
Question: What criteria is there for being an egg donor? And, does one have to live near the recipient and near the same clinic?
DR. COLVER: It is to the donor's advantage that she live near the clinic because she needs to undergo a significant amount of monitoring during the ovarian stimulation portion of the procedure. The recipient, however, needs to be close to a center capable of performing ultrasounds to monitor her endometrial lining. However, networking may be possible. We have performed procedures where either the donor or the recipient lived near a clinic in another state and they were able to come to Indianapolis for either the oocyte retrieval or the embryo transfer.
Question: Are egg donors and recipients always anonymous?
DR. COLVER: We have many patients who come to our clinic with known donors. These are most commonly sisters of patients. However, have also had other patients who have brought friends or acquaintances. Our donors who have come through the recruited oocyte donation program, however, remain anonymous.
Question: What about the risk to the egg donor, since she is taking fertility drugs and having surgery? What would be the egg donor's motivations?
DR. COLVER: The egg donor is counseled that there is always a risk of taking fertility medications and having surgery with respect to ovarian hyperstimulation and possible infection or bleeding. In dealing with many egg donors, the primary motivating factor is that they want to help someone be able to have a child.
Question: What would be some of the reasons that donor egg zift would not be successful?
DR. COLVER: Donor embryo transfer or donor ZIFT may not be successful due to poor oocyte or embryo development. Another major reason would be failure of implantation. This may be the most frustrating because we have no control over the implantation process.
Question: What is ZIFT and what does it mean?
DR. COLVER: ZIFT is zygote intrafallopian transfer. This acronym is for zygotes (fertilized eggs) which are transferred into the fallopian tube.
Question: What is the success rate for this process?
DR. COLVER: Success rate for donor eggs in our clinic last year was 63%.
Question: Once I make the decision to try this, how long is the wait for a donor?
DR. COLVER: The wait for a donor is approximately six months. This may be somewhat shorter or longer depending upon characteristics of the patient and whether or not a donor with those characteristics is available.
Question: Why choose this over surrogacy?
DR. COLVER: The advantage of donor egg over surrogacy is that the baby develops and is delivered by the recipient of the eggs rather than the surrogate mother. This is particularly important with respect to protection from a legal standpoint.
Question: Is there a higher rate of miscarriage or birth defects with this process? What about risks with a cryro cycle? (a cycle with thawed, previously frozen embryos.)
DR. COLVER: There is no increased risk of miscarriage or birth defects with donor eggs or with cryo preserved embryos.
Question: Would a pregnancy through donor egg be a fragile, high-risk pregnancy? And, what drugs would I be taking through this type of pregnancy?
DR. COLVER: A donor egg pregnancy would be considered a high risk pregnancy in those women who are older due to the medical concerns of the older pregnant patient. If the patient is young and healthy, the pregnancy would not be at a significant increased risk.
Question: How long has this procedure been available? Do you keep in touch with some of the new parents?
DR. COLVER: The first reported case was in 1983. Most of our patients keep in touch with us and notify us when they deliver.
Question: What is the best way to choose a doctor for Donor Egg Zift?
DR. COLVER: The best way to choose a physician for donor egg is to look for a clinic that has a high pregnancy rate. Most reputable clinics report their data yearly to the Society of Assisted Reproductive Technology (SART). This information is available to the public so they may choose a clinic with a good track record.
Question: How do your patients choose to explain this procedure to their children? Or do they?
DR. COLVER: There is a lot of discussion regarding whether or not patients elect to reveal to their children that they were conceived by donor egg. This is discussed extensively in the counseling prior to the procedure and may be an ongoing discussion between the couple. This is certainly handled individually and there is no universal right or wrong answer regarding this.
Question: Is this procedure available throughout the United States?
DR. COLVER: The procedure is available through many clinics in the United States. My advice for those who are interested in considering this would be to locate the nearest clinic with the best success rates in your area and then have a consultation with one of the physicians at the clinic.
Special thanks to Infertility specialist, Dr. Robert M. Colver for participating in Kay's Journal! Dr. Colver practices at the Indianapolis Fertility Center. This interview took place in September, 1997.