Sperm DNA Fragmentation Has a Negative Impact on Cumulative Live Birth Rate of IVF-ET/ICSI in Patients with Oligozoospermia

The relationship between sperm DNA fragmentation and in vitro fertilization (IVF) outcome was uncertain today. In the past, researchers studying the pregnancy outcome of IVF, mainly base on fresh embryo transplantation cycle, recently, cumulative live birth rate was consider as a new indicator of IVF successful rate which is used to evaluate the pregnancy outcome by fresh or thawed transferred embryos until live birth or use up all embryos in one oocyte collection cycle, is more comprehensive. The purpose of this research is to investigate the relationship between sperm DNA fragmentation and cumulative live birth rate. 1019 couples who were assisted by IVF in our center from Jan 2012 to Dec 2016 were studied according to inclusive criteria, and divided into four groups by DNA fragmentation index (DFI), which were determined by sperm chrome structure assay (SCSA), then the fertilization rate, No. of Embryo available and cumulative live birth rate between the groups were analyzed. Cumulative live birth curve was plotted to study the time to reach live birth, and Cox regression model was used in order to find out the factors affecting pregnancy outcome. Study results showed no significant difference in cumulative live birth rate between the four groups, but DFI ≥40% group were significantly lower than the other three groups. In the cumulative live birth curve figure, except the high DFI group, the curve of the other three groups is relatively close. Cox regression model suggest that DFI was not the main factor affecting pregnancy outcome. Further studies in these patients with oligozoospermia showed that when DFI increase, a decrease trend was appeared in cumulative live birth rate, and spend more time to reach live birth studied by the live birth curve. Cox model showed that DFI was the impact factor of pregnancy outcome in oligozoospermia patients. In conclusion, abnormal sperm DNA fragmentation have a negative impact on cumulative live birth rate in patients with oligozoospermia, but further research was still needed.