Women may need more than two cycles of fertility treatments to get pregnant and older women may need to use donor eggs to achieve success, a study found.
Women younger than 31 gave birth to a child 63 percent to 75 percent of the time with a third cycle of in vitro fertilization, while women ages 40 to 42 had a 19 percent to 28 percent success rate and those 43 and older had a 7 percent to 11 percent success rate, according to a study in the New England Journal of Medicine. When using donor eggs, the likelihood of delivering a child was 60 percent to 80 percent for all ages, the research showed.
Fertility treatments are expensive and many insurance companies only cover a portion of the expenses for two to three cycles, the researchers said. Women tend to get discouraged when they don't get pregnant after the first treatment and abandon the effort, the study said. The study found that the more fertility treatments a woman undergoes, the better her chance of getting pregnant, said Barbara Luke, the lead author.
"For patients perhaps it's saying to look at treatment over a series of cycles rather than just one cycle," Luke, a professor in the Department of Obstetrics, Gynecology and Reproductive Biology at Michigan State University in East Lansing, said in a telephone interview. "What this data shows is the live birth rate continues to increase with continued therapy.
"For insurers, this actually shows it continues to climb past three cycles. Two to three cycles are often covered by insurance. These findings may help insurance companies rethink their policy," she said.
The study is the first national analysis linking fertility cycles with live birth rates in the U.S., she said.
In the general population, the natural fertility rate for healthy women is about 20 percent a month, the authors wrote. The chance of conceiving spontaneously is 45 percent after three months of trying, 65 percent after six months and 85 percent after 12 months, the paper said.
A couple is considered infertile after trying to get pregnant for one year without success or six months if the woman is older than 35, according to RESOLVE: The National Fertility Association, a nonprofit support and education group. About 12 percent of women of childbearing age, or one in eight couples, are affected by infertility, the group said on its website.
Also, only 15 U.S. states mandate that health insurance include some infertility coverage but the policies vary, according to the association.
Researchers in the study used data from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System database from 2004 through 2009 to estimate live-birth rates. They then calculated an estimate assuming that women who didn't return to treatment wouldn't have a live birth, and an optimal estimate that those women would have live-birth rates similar to those continuing treatment.
The study included 246,740 women who underwent a combined 471,208 cycles of fertility treatments and had 140,859 live births. In the study, 57 percent of the women had a live birth and a live birth occurred in 30 percent of the cycles.
The researchers found that the two major factors that affect the success rate of fertility are the woman's age and quality of the embryos. For older women, switching to donor eggs rather than using their own improved their chance of conceiving, Luke said.
About 25 percent of women quit after one cycle and 33 percent after two cycles, Luke said.