More than 40 percent of patients who experience total fertilization failure after an IVF cycle have a baby at a later attempt, researchers report.
Total fertilization failure after IVF or ICSI can be very frustrating for patients and clinicians alike.
Little information has been available about patients' chances of success in the future or how changes in treatment could improve the likelihood of fertilization in later cycles.
To investigate, Donna Kinzer (Boston IVF, Waltham, Massachusetts, USA) and colleagues conducted a retrospective analysis of data for 555 couples who experienced total fertilization failure during conventional IVF or ICSI.
They found that 44 percent of IVF patients who chose to continue treatment eventually gave birth. This equated to a delivery after 25 percent of embryo transfers and 22 percent of cycles.
After ICSI, 36 percent of couples had a child, after 23 percent of their embryo transfers, in 18 percent of their cycles.
Results also showed that fewer mature oocytes were used in the transfers that ended in complete fertilization failure, compared with earlier or later transfers, Kinzer et al report.
They say these results suggest that "total fertilization failure is not related to sperm parameters but rather is a result of suboptimal response to ovarian stimulation.
They add: "If subtle improvements in oocyte yield can be effected, this may increase the chance of fertilization in subsequent cycles for these patients."
Source: Fertility and Sterility 2008; 90: 284-8