Egg Donation

By Steven T. Dodge, M.D.
California North Bay Fertility Medical Associates
Santa Rosa, CA, USA

One of the most exciting and significant advances in reproductive medicine in the past decade has been the advent of egg donation, a type of in vitro fertilization that allows the eggs of one woman to be given to another. The process gives women with previously poor or even hopeless fertility prognoses an excellent chance to become pregnant and subsequently deliver a healthy baby.

The most common reason for egg donation is age factor infertility. A woman's egg supply is fixed before birth and every day a number of eggs is lost. Ultimately the egg supply reaches zero and menopause occurs, typically at age 51 (plus or minus 10-12 years). Long before menopause the egg supply and quality of remaining eggs decreases to such a level that pregnancy becomes unlikely. Thus women experience significantly reduced fertility 10-15 years before menopause. This is not a well known fact and hence many women have planned their lives and careers based on the mistaken belief that their fertility will remain normal well into their forties.

As a result, a majority of women seeking egg donation are over forty and have found their egg supply to be too low to allow a reasonable chance of pregnancy. Others, in their thirties and occasionally even their twenties, have run out of eggs much earlier than usual. Sometimes this is in the form of premature menopause (or premature ovarian failure) while in others they continue to have periods but nonetheless have extremely low egg supplies. Still others may have had their ovaries surgically removed (for ovarian tumors of various kinds) or were born without functional ovaries (gonadal dysgenesis or Turner's syndrome).

Fortunately egg donation is very effective, producing the highest success rate of all infertility treatments. In cases where the recipient's uterus is found to be normal (by pelvic exam and ultrasound) and the egg donor is less than 34 years old, a viable pregnancy rate of nearly 60% per treatment cycle is possible. In addition about 70% of recipient couples will have enough good quality extra embryos to freeze for another attempt later on.

Egg Donors

Most egg donors are healthy young women less than 34 years old (most, in fact, are less than 30) and come from all walks of life and ethnic backgrounds. Some are college or graduate students, others are working women hoping to go back to college and yet others are homemakers. While they receive a fee for their services they are all very motivated to help couples achieve their dream of giving birth to a healthy baby.

Once a potential donor has been selected by a recipient couple she undergoes medical and psychological screening tests which include a careful medical history, a pelvic examination (including a pelvic ultrasound), blood tests to look for infectious diseases (HIV, hepatitis B, hepatitis C, syphilis and HTLV-I), cervical cultures for gonorrhea and chlamydia and hormone blood tests to predict ovarian response to the fertility drugs. The psychological screening includes an interview with a therapist experienced in this area and a specialized personality inventory test called the MMPI.

Treatment Process

It is best to think of the egg donation process as an in vitro fertilization (IVF) cycle split between two women, the donor and the recipient. Both women take birth control pills for a few weeks and then receive an injection of Depo-Lupron. This serves to synchronize the menstrual cycles of the women and get both of them to the Òstarting gateÓ at the same time. The recipient then begins receiving estrogen in the form of an estradiol valerate injection twice a week. This estradiol is the same main estrogen normally produced by the ovaries.

Meanwhile the donor receives daily injections of fertility drugs (such as Follistim, Fertinex, Repronex, Gonal-F, Humagon, HMG or Pergonal) which help mature a group of eggs in her ovaries. Usually 7-12 days of fertility drugs are required before the eggs are mature. Soon after this point the recipient begins progesterone, the only other hormone necessary to maintain pregnancy. This is in the form of oral capsules, a daily injection and/or Crinone vaginal cream. It has long been our custom to teach a spouse, relative, friend or neighbor to give injections so frequent trips to our office are not needed.

The eggs are gathered at the Òegg retrievalÓ which is a procedure done in our office under light anesthesia (actually intravenous sedation) administered by an anesthesiologist. A needle guided by ultrasound is used to pass through the top wall of the donor's vagina and into the fluid filled egg sacs (ÒfolliclesÓ) in her ovary. This may sound complex but is actually quite easy and causes no pain, thanks to the anesthesia. It takes about 15 minutes to gather the eggs and the donor is ready to go home 60-90 minutes later. The fluid we remove from the follicles is given immediately to our embryologists who use their microscopes to find the otherwise invisible eggs.

The eggs are usually inseminated a few hours after retrieval with sperm from the recipient's husband. This is done by our embryologists who are also responsible for culturing the fertilized eggs (now called embryos) until the time of transfer to the recipient's uterus. The embryo transfer is usually done 3 days after the egg retrieval when the embryos are at the 4-10 cell stage. This is a very simple procedure and is nearly always completely painless. It is very much like a routine pelvic exam and involves the passage of a very small plastic catheter through the recipient's cervix. A tiny drop (20-30 microliters) of culture media with the microscopic embryos suspended within is deposited in the upper reaches of the uterus. Good quality embryos that are not transferred can be frozen for a later transfer (in a few months if the first transfer is not successful or several years later if it is).

Risk to Recipent

For recipients the main significant risk of the egg donation process is that of pregnancy itself (or one of its complications such as miscarriage or ectopic pregnancy). While medical complications and even maternal death are more common in women over age 40, the results with egg donation have been very good so far. This is undoubtedly because of the careful medical screening done before women are allowed to proceed with the egg donor process. The message is that pregnancy can be safely undertaken up until age 55 (and possibly older) if a woman's health is excellent.

A special risk of egg donation is that of too much success (multiple pregnancy). Before the power of this process was understood large multiple pregnancies (triplets, quadruplets and even quintuplets) were not unusual. Now only a small number of the healthiest embryos are transferred. The high success rate has been maintained and the really large multiples (quadruplets, quintuplets) have been eliminated. Triplets have been reduced to a very low level, leaving only twins as a continued problem. About 30% of egg donation pregnancies are twins. Since the outcome is usually good, twins are not considered to be a true complication of the process but, on the other hand, we prefer to help couples have one baby at a time.

Because the eggs come from another person there is also a theoretical risk of the transmission of disease, such as hepatitis or AIDS, to the recipient. Therefore all egg donors are pre-screened for infectious diseases and thus far no case of disease transmission has been reported.

Risk to Egg Donors

We have been involved in ED since 1990, which was soon after the current IVF based approach was developed. So far the safety record for donors has been excellent. Nonetheless we counsel all potential donors about 4 important actual or potential risks. These are anesthesia complications, risk of infection after the egg retrieval, risk of ovarian hyperstimulation and potential long term health hazards of the fertility drugs. The latter risk is a theoretical one as thus far no increased risks of any type of cancer (including breast, ovary and uterine) have been reported. It is nevertheless clear that we don't yet know all there is to know about long range health problems from the egg donor process and won't for many years to come. In recognition of this fact we have a policy that young women should serve as egg donors a maximum of 6 times during their lifetime.

Legal Concerns

The main fear that recipient couples have is that their donor might turn up on their doorstep some day demanding maternal rights. This has not yet happened and, for several reasons, we believe is very unlikely to occur in the future. The anonymity of the process is one layer of protection while the consent forms and legal contracts used for this process is another. The fact that sperm banks have had no claims for paternal rights arise from donors in 50 years of sperm donation in this country is also very reassuring. And yet it remains true that anyone can sue just about anyone else for anything. We nevertheless believe the risk of a future legal complication from egg donation is very, very small.