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Although age is not an absolute barrier to pregnancy, the proven fact is that female fertility decreases with age, while the situation with men is a bit different. Women are born with all the eggs that they will ever have in their lives while, men, on the other hand, make fresh sperm continuously throughout their lives.
Reproduction – facts
Reproduction is the most important function in the life of an organism, and all other processes, including senescence and death, are shaped to serve it. There are different models of reproduction. The most common are semelparous and iteroparous. Semelparous organisms reproduce by a single reproductive act. Annual and biennial plants are semelparous, as are many insects and a few vertebrates, notably salmon and eels. Iteroparous organisms, on the other hand, reproduce recurrently over a reproductive span that usually covers a major part of the total life span.
Human fertility depends on various factors such as:
- sexual behavior,
Male and female reproductive system
Most people are not aware that women are born with a fixed number of eggs - about 400,000. Women’s eggs form in her ovaries during the fourteenth week of fetal growth and they will remain there until puberty.However, this number decreases even during early childhood, bringing the number closer to 300,000 by the time a woman reaches puberty.
Over the next 35 to 40 years of reproductive life, only 400 to 500 eggs will ovulate and at menopause only a few hundred will remain.
At puberty, the eggs will eventually start to mature one-by-one. At ovulation, the egg bursts from the ovary sometimes causing a small, sharp pain. If the egg is not fertilized by the male sperm, the egg will break down within 24h into its components and be reabsorbed by the body.
Men on the other hand continually produce sperm throughout their lives.