General Discussion
In reply to the discussion: Study: Men of All Ages Want Women in Their Mid-20s [View all]Xithras
(16,191 posts)Male degradation typically results in reduced sperm count and motility. This reduces the odds of a pregnancy. However, even men in their 80's are capable of generating sperm without defect.
Female reproductive degradation usually results in decreased ovum quality.
An older man is less likely to initiate a pregnancy, but as the healthiest sperm with the best motility are more likely to be the initiators of the pregnancy, the odds of the pregnancy being successful are much higher. Ova degradation, on the other hand, leads too higher rates of morality and birth defects no matter how efficient the rest of the female reproductive system is.
Part of the difference is the way they are created. A 35 year old woman is generally attempting to fertilize 35 year old ova, which have 35 years of accumulated genetic damage. Male sperm, on the other hand, live two months at the absolute longest (presuming no ejaculation, sperm typically exist between 40 and 70 days in the male body before they die off). The male body becomes less efficient at creating sperm as it ages, but most male bodies still produce a substantial number of genetically flawless sperm well into old age.