1. Colorado Center for Reproductive Medicine, Englewood
- Number of ART cycles and transfers in 2002: 912 (Nearly all ART cycles use IVF. If a patient uses donor eggs or frozen embryos, the CDC labels the procedure a transfer rather than a cycle.)
- Percentage of ART cycles from non-donor fresh embryos resulting in live births in 2002: 60% (under age 35), 51% (ages 35-37), 44% (ages 38-40), 23% (ages 41-42)
- Boasts 2002 IVF success rates that are twice the national average for women ages 38 to 42 who are using their own eggs
- Is researching ways to improve the chance of pregnancy for patients with endometriosis or polycystic ovarian syndrome
- Attracts 40% of its patients from outside the Colorado area
For most women trying IVF, physicians return two to seven fertilized eggs, called embryos, hoping one will implant. But about 30% of women who become pregnant are carrying twins, and 7% are expecting triplets or more. "Twin pregnancies are at a three- to five-fold greater risk for pregnancy complications and perinatal mortality [death between 28 weeks gestation and a week after delivery] compared to carrying one fetus. With triplets, there's at least a seven-fold greater risk," says Eric Surrey, M.D., medical director of the Colorado Center for Reproductive Medicine (CCRM) and president of the Society for Assisted Reproductive Technology, a top group in the field.
Dr. Surrey's team recruited patients, 48 in two years, between ages 26 and 48 to study the feasibility of returning just one embryo. "This is common in some Western European countries, but the success rate is about 30% to 35%," says Dr. Surrey. "We wanted to see if we could improve on those rates."
Earlier work at CCRM paved the way for embryos, which used to be returned three days after fertilization, to develop into blastocysts, a process that takes about two more days. Waiting longer gives doctors a better idea of the embryos' quality and helps them decide which one has the best chance of survival.
Half the women in the study received one embryo, and the remainder got two. All were given the option of freezing leftover embryos for use at another time. In the group receiving a single embryo, 61% had a clinical pregnancy (a heartbeat shown on ultrasound) and there were no twins. By comparison, the ongoing pregnancy rate in the group receiving a pair of embryos was 76%, but nearly half the pregnancies resulted in twins. "The slightly lower chance for pregnancy in the single-embryo group outweighs the significant risks associated with multiples," says Dr. Surrey. "Larger trials will more carefully define just who the ideal candidates for this approach will be."
2. The Center for Reproductive Medicine and Infertility at NewYork-Presbyterian Hospital/Weill-Cornell Medical Center, New York City
- Number of ART cycles and transfers in 2002: 2,012
- Percentage of ART cycles from non-donor fresh embryos resulting in live births in 2002: 48% (under age 35), 43% (ages 35-37), 30% (ages 38-40), 18% (ages 41-42)
- Is one of the most experienced centers in the U.S., with 11,000-plus babies born through conventional IVF and 4,000 through ICSI -- a technique that injects a single sperm into an egg; ICSI, invented by the center's lab director, is a must for couples with severe male factor infertility
- Specializes in preserving fertility in cancer patients
- Performed the first genetic testing on embryos for sickle cell anemia and retinoblastoma, an inherited eye cancer
Priding themselves on a difficult caseload, doctors at The Center for Reproductive Medicine and Infertility (CRMI) conduct more than one-third of their IVF cycles on patients who have had two or more failed attempts at other clinics. "Other fertility specialists send us their patients who haven't gotten pregnant," says the clinic's director, Zev Rosenwaks, M.D.
Because many couples who have experienced several unsuccessful cycles want to put back more embryos than they did on the first few tries, the center's triplets rate in women ages 35 to 37 is the highest of our top 10. But its live-birth rate using non-donor fresh embryos is remarkable: 30% to 70% above the national average, depending on the woman's age. How is that possible? In a word: research. Since 2002, the center has published more than 200 studies in medical journals -- the most of our survey. Among them: autologous human endometrial co-culture, which means growing a couple's embryos on a woman's endometrial cells instead of in the standard IVF liquid.
Before starting an IVF cycle, a woman undergoes an endometrial biopsy, in which a small piece of her uterine lining is removed. The sample is frozen until the next month, when the woman's eggs are retrieved, fertilized, and put on her endometrial cells to grow. A study by CRMI researchers on 1,000-plus patients, who on average had three failed IVF attempts, found the technique improved embryo quality and resulted in an impressive clinical pregnancy rate of 42%.
3. University Fertility Consultants at Oregon Health & Science University, Portland
- Number of ART cycles and transfers in 2002: 505
- Percentage of ART cycles from non-donor fresh embryos resulting in live births in 2002: 34% (under age 35), 39% (ages 35-37), 34% (ages 38-40), 7% (ages 41-42)
- Reported the first live birth from an ovarian tissue transplant in a primate, paving the way for cancer patients to freeze their ovarian tissue before treatment
- Minimizes high-risk pregnancies; while the center's live-birth rate for women ages 35 to 37 undergoing IVF with their own eggs is about 25% above the national average (39% vs. 31%), its percentage of pregnancies with multiple fetuses is roughly half the average in that age range
- Boasts a very experienced lab staff
Some fertility centers don't allow women to try IVF with their own eggs if their level of follicle stimulating hormone (FSH) is over 10. FSH, produced by the pituitary gland, causes eggs to mature; a high level of it, measured on the third day after menstruation begins, may indicate that few eggs are left in the ovaries.
But physicians at University Fertility Consultants routinely take patients whose FSH is up to 15. In a recent study of 350 women over age 35, they found that the clinical pregnancy rate for women with FSH levels of 10 to 15 was about 33% -- below the 42% pregnancy rate when a patient's FSH is under 7, but still pretty good. "My overall success rates are lower because about 25% of the women in my caseload have high FSH levels," says the center's director, Kenneth Burry, M.D. "But I don't feel comfortable referring patients for egg donation when they have a reasonable chance of success using their own."
4. New York University School of Medicine, Program for In-Vitro Fertilization, Reproductive Surgery, and Infertility, New York City
- Number of ART cycles and transfers in 2002: 1,362
- Percentage of ART cycles from non-donor fresh embryos resulting in live births in 2002: 45% (under age 35), 42% (ages 35-37), 24% (ages 38-40), 17% (ages 41-42)
- Sees many difficult cases; about 70% of patients have failed at least one IVF cycle elsewhere
- Offers a patient library equipped with computers
- Is developing an egg-freezing program
Thirteen years ago, Jamie Grifo, M.D., Ph.D., was the first fertility specialist in the U.S. to successfully perform pre-implantation genetic diagnosis (PGD), the screening of an embryo for a specific inherited condition, such as cystic fibrosis. "It's heartbreaking to talk to couples whose children have died from a genetic disease," says Dr. Grifo, director of the division of Reproductive Endocrinology at New York University. "They tell me they couldn't go through it again -- all they want is a healthy baby."
Dr. Grifo, who has been at NYU for the last 10 years and did his early work with PGD at Yale and Cornell, has begun to apply the technique to women who have suffered recurrent miscarriages. "We're searching for abnormalities in chromosomal numbers, and often we find them," he explains. "Last year, I started one of my patients, who had gone though five miscarriages, on an IVF cycle. She produced 11 eggs, which fertilized. When we checked them, we found that only two were normal. We put both back, one implanted, and she gave birth recently."
In fact, more than 70 babies have been born to NYU clients using the technique -- which involves making a hole in the outer coating of the embryo and removing a single cell for analysis -- and the clinical-pregnancy rate per cycle is about 40%. "If done properly, it really doesn't make the embryo much less likely to implant," he says. What about future consequences? Although long-term effects are still unknown, a recent study of 754 PGD babies suggests that they're no more likely to have birth defects than children conceived conventionally.
5. The Infertility Center of St. Louis at St. Luke's Hospital
- Number of ART cycles and transfers in 2002: 176
- Percentage of ART cycles from non-donor fresh embryos resulting in live births in 2002: 35% (under age 35), 26% (ages 35-37); there were too few cycles in women ages 38-42 to report the results as a percentage
- In 2002, performed the greatest percentage of IVF cycles due to male factor infertility of any center in the country; many cases involved very complex problems
- Has completed more than 4,000 microsurgical vasectomy reversals over the last 30 years, reporting in a recent study that nearly 90% of patients were able to impregnate their partners
- Conducted the world's first ovarian transplant, in which an infertile identical twin was given one of her sister's ovaries; the woman had a healthy baby girl in June
Over the last 30 years, Sherman Silber, M.D., founder of the Infertility Center of St. Louis, has published more than 200 studies on infertility, pioneering or advancing techniques that help men with little or even no sperm become fathers. Much of his research has focused on the estimated 2% to 5% of infertile men with congenital absence of the vas deferens, a condition in which the tubes that carry sperm from the testes haven't developed normally. "These men make sperm, but it's not in the ejaculate," says Dr. Silber. "We do a procedure to extract sperm from the testicles."
He's usually able to retrieve sperm to fertilize eggs through ICSI (see page 3 for ICSI description). He often recommends that couples in this situation have their embryos screened for genetic abnormalities since a higher percentage of them may contain the wrong number of chromosomes even though they look normal. "By doing the testing, we can boost the chance of a live birth from about 35% to 45%," he says.
Filling his practice with extraordinarily difficult cases has taken a toll on Dr. Silber's success rates, but he doesn't mind. "For me, it's not about the numbers," he says. "It's about giving couples what they want most -- a child."