Live-birth rate associated with repeat in vitro fertilization treatment cycles

Smith, A. D.A.C., Tilling, K., Nelson, S. M. and Lawlor, D. A. (2015) Live-birth rate associated with repeat in vitro fertilization treatment cycles. JAMA: Journal of the American Medical Association, 314(24), p. 2654. (doi: 10.1001/jama.2015.17296) (PMID:26717030)

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.

• Item Type: Articles
• Additional Information: Drs Smith, Tilling, and Lawlor work in a unit that receives funding from the UK Medical Research Council (http://www.mrc.ac.uk) (MC_UU_12013/5 and MC_UU_12013/9), and Dr Lawlor receives support from a National Institute for Health Research Senior Investigator award (NF-SI-0611-10196). This work is also supported by a grant from the Wellcome Trust (http://www.wellcome.ac.uk), which pays Dr Smith’s’ salary (WT094311MA).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Nelson, Professor Scott and Smith, Professor Andrew
• Authors: Smith, A. D.A.C., Tilling, K., Nelson, S. M., and Lawlor, D. A.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Journal Name: JAMA: Journal of the American Medical Association
• Publisher: American Medical Association
• ISSN: 0098-7484
• ISSN (Online): 1538-3598