Increasing IVF cycles increases chances for live birth

In vitro fertilization (IVF) is often limited to 3 or 4 treatment cycles. However, new research shows extending the number of IVF cycles up to nine, birth rate increased. In fact, 65 percent of women achieved a live birth by the sixth cycle.

In vitro fertilization is commonly stopped after 3 or 4 unsuccessful embryo transfers, with 3 unsuccessful transfers labeled as "repeat implantation failure."  However, Debbie A. Lawlor PhD at the University of Bristol, United Kingdom, examined IVF cycle data and found the likelihood of a live birth continues to increase with more than 4 cycles.

The study included 156,947 U.K. women who received 257,398 IVF ovarian stimulation cycles between 2003 and 2010. They were followed up until June 2012. The median age at start of treatment was 35 years, and the median duration of infertility for all cycles was 4 years. Her study appeared in the December 22/29 issue of The Journal of The American Medical Association or JAMA.

• In all women, live-birth for one cycle was 29.5 percent. This remained above 20 percent and included up to a fourth cycle. Yet the cumulative prognosis for live-birth adjusted across all cycles continued to increase up to a ninth cycle. By the sixth cycle, 65 percent of women had achieved a live birth.

• In women younger than 40 years using their own oocytes (eggs), the live-birth rate for the first cycle was 32 percent and remained above 20 percent up to and including a fourth cycle — achieving a cumulative adjusted live-birth rate of 68 percent.

• For women 40 to 42 years of age, the live-birth rate for the first cycle was just 12 percent, with 6 cycles achieving a cumulative prognosis-adjusted live-birth rate of 31.5 percent.

• For women older than 42 years, all rates within each cycle were less than 4 percent.

• No age differential was observed among women using donor eggs.

• Rates were lower for women with untreated infertile male partners, unless IVF was facilitated with either intracytoplasmic sperm injection (in which a single sperm is injected directly into an egg) or sperm donation.

Women younger than 40, those using donor oocytes and those with male partner-related infertility treated with either intracytoplasmic sperm injection or sperm donation — achieved a live birth after five or six cycles, over a median two years of trying. Similar rates existed in couples trying to conceive over an average of one year and not using any form of treatment.

The number of eggs retrieved after ovarian stimulation in one cycle did not influence the live birth success rate in subsequent cycles. This is important because couples are often told their chances of success with future treatments are likely to be poor if they had no or only a small number of eggs retrieved in a cycle.

"These findings support the efficacy of extending the number of IVF cycles beyond 3 or 4," the authors conclude.

Researchers note that for some couples, the emotional stress of repeat treatments may be undesirable, and the cost of a prolonged treatment course, with several repeat oocyte stimulation cycles, may be unsustainable for health services, insurers, or couples.

"However, we think the potential for success with further cycles should be discussed with couples."

Associated Editorial
Repeated In Vitro Fertilization Cycles for Infertility

"For clinicians, it is important that these data be shared with couples so that they can make a truly informed decision. This will require time and expertise in communication. For policy makers, revising the National Assisted Reproductive Technology Surveillance System to allow reporting of outcomes on a per-couple basis (including oocyte donors) would provide significantly more useful information for decision-making purposes."

Evan R. Myers MD, MPH, Duke University Medical Center, Durham, N.C., in an accompanying editorial.

Abstract
Importance The likelihood of achieving a live birth with repeat in vitro fertilization (IVF) is unclear, yet treatment is commonly limited to 3 or 4 embryo transfers.

Objective
To determine the live-birth rate per initiated ovarian stimulation IVF cycle and with repeated cycles.

Design, Setting, and Participants Prospective study of 156?947 UK women who received 257?398 IVF ovarian stimulation cycles between 2003 and 2010 and were followed up until June 2012.

Exposures In vitro fertilization, with a cycle defined as an episode of ovarian stimulation and all subsequent separate fresh and frozen embryo transfers.

Main Outcomes and Measures Live-birth rate per IVF cycle and the cumulative live-birth rates across all cycles in all women and by age and treatment type. Optimal, prognosis-adjusted, and conservative cumulative live-birth rates were estimated, reflecting 0%, 30%, and 100%, respectively, of women who discontinued due to poor prognosis and having a live-birth rate of 0 had they continued.

Results Among the 156?947 women, the median age at start of treatment was 35 years (interquartile range, 32-38; range, 18-55), and the median duration of infertility for all 257?398 cycles was 4 years (interquartile range, 2-6; range, <1-29). In all women, the live-birth rate for the first cycle was 29.5% (95% CI, 29.3%-29.7%). This remained above 20% up to and including the fourth cycle. The cumulative prognosis-adjusted live-birth rate across all cycles continued to increase up to the ninth cycle, with 65.3% (95% CI, 64.8%-65.8%) of women achieving a live birth by the sixth cycle. In women younger than 40 years using their own oocytes, the live-birth rate for the first cycle was 32.3% (95% CI, 32.0%-32.5%) and remained above 20% up to and including the fourth cycle. Six cycles achieved a cumulative prognosis-adjusted live-birth rate of 68.4% (95% CI, 67.8%-68.9%). For women aged 40 to 42 years, the live-birth rate for the first cycle was 12.3% (95% CI, 11.8%-12.8%), with 6 cycles achieving a cumulative prognosis-adjusted live-birth rate of 31.5% (95% CI, 29.7%-33.3%). For women older than 42 years, all rates within each cycle were less than 4%. No age differential was observed among women using donor oocytes. Rates were lower for women with untreated male partner–related infertility compared with those with any other cause, but treatment with either intracytoplasmic sperm injection or sperm donation removed this difference.

Conclusions and Relevance Among women in the United Kingdom undergoing IVF, the cumulative prognosis-adjusted live-birth rate after 6 cycles was 65.3%, with variations by age and treatment type. These findings support the efficacy of extending the number of IVF cycles beyond 3 or 4.

Authors report no Conflicts of Interest.

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Dec 31, 2015   Fetal Timeline   Maternal Timeline   News   News Archive   

Human egg held at the end of a pipete (RIGHT) while injected with male sperm (LEFT).
This procedure is known as an intracytoplasmic sperm injection.

Image Credit: Public Domain