This paper is based on a Cochrane review of the same title by the same authors published in The Cochrane Library, issue 3, 2003 (see www.CochraneLibrary.net for information) with permission from the Cochrane Collaboration-John Wiley and Sons. Cochrane reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and The Cochrane Library should be consulted for the most recent version of the review.
Background: The objective of this review was to investigate whether ICSI improves live-birth rate in comparison with IVF in couples with non-male factor subfertility.
Methods: We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched 30 May 2002), the Cochrane Controlled Trials Register (Cochrane Library Issue 2, 2002), PubMed (January 1992 to September 2003) and reference lists of articles. Trials were included if they compared the effects of ICSI and IVF on live births, pregnancy and fertilization outcomes. Only randomized studies were included in this review. Two reviewers extracted data independently.
Results: There were no randomized data comparing live-birth rates. The single identified study did not find a difference in pregnancy rates (OR 1.4, 95% CI 0.95-2.2). There were no randomized data on miscarriage rates, or on other adverse events such as congenital malformations that may be of concern (415 couples randomized). Two studies used alternation to assign their couples and did have live birth as an outcome. These studies showed a significantly higher fertilization rate in the IVF group, but no difference in pregnancy, miscarriage or live-birth rate.
Conclusions: Whether ICSI should be preferred to IVF for cases of non-male factor subfertility remains an open question. Further research should focus on live-birth rates and adverse events.