Paternal age and outcome of intracytoplasmic sperm injection.
In a retrospective study, the outcome of intracytoplasmic sperm injection (ICSI) in two age groups of men was studied. Couples with male partners aged 50 years and over (group A) (n = 227) with mean age of 53 +/- 5 years were compared with couples with younger age-group male partners (group B) (n = 227) with a mean age of 38.4 +/- 5.8 years. The control group of younger men was selected so that the women's age matched between the two groups. There was no significant difference in pregnancy rate between the two groups (37.9 versus 36.6%; OR = 1.06, 95% CI = 0.72-1.55). There was also no significant difference in the pregnancy rate between men aged 60 years and over as compared with men aged 50 to 59 years (OR = 1.00, 95% CI 0.74-1.37). However, the long-term outcome of these pregnancies needs further investigation. Semen analysis showed significantly lower motility in group A (37.4 +/- 20.4) versus group B (46.4 +/- 15.5; P < 0.0001). There was a significantly higher fertilization rate in younger men (P < 0.0001; OR = 1.36, 95% CI = 1.19-1.55), but this did not affect the pregnancy rate. In conclusion, it appears that paternal age has no effect on the pregnancy rate after ICSI.