Human egg freezing is going mainstream. The biggest reason: it works. A handful of studies suggest the success rate for women undergoing in vitro fertilization (IVF) is just as high when using frozen eggs as fresh ones. The results increase the flexibility and control women can have in their reproduction and their careers.
Egg freezing and IVF follow the same steps, but the timing of pregnancy is different. A woman first takes fertility shots to boost her egg production and then has them extracted. In IVF the fresh eggs are combined with sperm and implanted in the patient's or donor's womb so pregnancy can begin immediately. In the freezing procedure a woman’s eggs are frozen and saved for pregnancy at a later date. Both procedures implant the eggs in the same way. Researchers compared pregnancy rates for fresh and frozen eggs and found they had similar success—57 percent for the frozen eggs in one study and 63 percent in another, compared with a 55 percent rate for fresh eggs.
Like IVF, egg freezing takes a lot of time and effort—and plenty of money. The elaborate, multistep-harvesting process can take two to five weeks and cost more than $10,000. And then there are many more steps—and plenty of additional costs—associated with thawing, fertilizing and implanting the eggs years later.
Even so, the procedure is growing in popularity, according to Jamie Grifo, co-director of the Oocyte Cryopreservation Program at New York University’s Fertility Center and an internationally prominent infertility doctor. "The reason I’m so busy is that many women are delaying childbearing,” he says, noting that it is harder to become pregnant using eggs at an older age. “Most people want their own eggs, not somebody else’s, so egg freezing becomes an insurance policy to be your own egg donor."
Whereas men produce new sperm cells throughout their lives, women are born with all of the eggs they’ll ever have, and they lose one with each period. Over time, the quality of their remaining eggs declines, becoming more likely to have genetic abnormalities. For example, about half of a 30-year-old woman’s eggs are chromosomally normal but by age 44 this figure drops to 2 percent, according to Grifo. That’s why he advises women interested in egg freezing to do so before age 38.
The procedure was developed in the 1980s for women with cancer, so they could preserve their eggs before losing fertility from chemotherapy. Then in 2012 the American Society of Reproductive Medicine declared egg freezing was no longer experimental, setting off a boomlet in the procedure. Grifo’s clinic at N.Y.U., one of the largest in the U.S., has done more than 2,200 egg freezing procedures to date—85 percent of them for elective reasons.
Also contributing to the buzz about egg freezing are announcements by Facebook, Apple and some other companies that they will pay for employees’ elective procedures. Although most insurance providers cover infertility treatments, few cover the high price of elective egg freezing. Egg extraction costs $10,000, storing them is about $1,000 per year and using them adds another $5,000, according to Grifo.
Kristin Bendikson, a doctor who specializes in egg freezing at the University of Southern California Fertility Clinic, says the process is overall positive for her patients but that it can be an incredibly emotional experience. "It's not a guarantee that those eggs are going to lead to a pregnancy," she says. "If you don't get pregnant, that can be very disheartening." The process involves several trips to the doctor, days of fertility shots, some slight discomfort and the emotional duress that accompanies fertility treatments. But bearing this, a woman can have her frozen insurance in the bank within weeks and still be able to conceive years later.
Here’s how the process unfolds:
1. Fertility Consultation
One hour
Meet with doctors, nurses and a financial counselor to discuss a fertility plan, medication options and a financial strategy.
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2. Pre-preparation
0–21 days, depending on the current stage of the menstrual cycle
If women have been on the contraceptive pill for more than five years, Bendikson says she has them stop taking it for a couple months before they start the egg freezing process. A week or two before fertility shots begin, take birth control pills to suppress egg production.
3. Ovarian stimulation
10–14 days
Take one to three daily hormone injections (via a shot administered to the stomach or upper thigh) to enable the body to produce as many viable eggs as possible. Attend five to seven doctors’ visits during this time to monitor progress with blood tests and ultrasounds.
Possible side effects: cramps, weight gain, irritability, pain at injection site, headache
4. Trigger shot
1.5 days before egg extraction
Administer a final hormone shot to stimulate the eggs to mature and be ready for removal.
5. Egg harvest
10–20 minute procedure plus an hour or so of recovery time
The patient is put under light sedation. Doctors use a transvaginal ultrasound to visualize where the eggs are as they are travel down the fallopian tubes.
Possible side effects: bloating, cramps, fatigue
Harvest: zero to 45 eggs (the average is 10 to 20)
6. Freezing
One–three hours
Medical professionals evaluate the health of harvested eggs in the lab. To prepare the healthy ones for freezing, they remove the liquid using chemical solvents in a process called vitrification. Ice crystals can damage the cytoskeleton of the egg, so removing water is key to their preservation. Eggs are then loaded for storage into cryo-vials and plunged into liquid nitrogen to flash freeze them within seconds.
7. Fertilization
Months to years later
All of the eggs are thawed, evaluated for their viability and injected with sperm. The best embryo candidate (the one dividing most successfully) is injected into the uterus with a catheter. Grifo says about 90 percent of eggs survive freezing, about 70 percent are successfully fertilized and about half become babies. Any leftover unused eggs can be refrozen for another pregnancy.
Possible side effects: psychological distress if the procedure is unsuccessful