- In This Feature
- The Egg’s Journey
- Family Planning Boards
Family Planning Boards
The eggs in the ovary are vulnerable to tobacco, chemicals, and radiation. Once eggs are damaged or destroyed, they are not replaced. The delicate balance between the hypothalamus and pituitary is vulnerable to stress, obesity, diet, exercise, and many other factors that can be managed through preconception preparation.
In men, fertility means the ability to make a woman pregnant. To do this, the man's reproductive system needs to produce and store sperm. It also needs to transport sperm outside of his body, so it can enter the woman's reproductive tract.
There are several aspects of the male reproductive system that are analogous to the female reproductive system. Testosterone and sperm production are regulated by LH and FSH produced by the pituitary gland. Unlike the female reproductive system, there is no cyclicity and the male continually produces millions of sperm until death.
The entire process of spermatogenesis (production and maturation of the sperm) takes place in the testicle, where conditions are generally optimal for sperm production: a temperature 2° centigrade lower than the core body temperature and a barrier between the blood and the testis (to prevent the production of sperm antibodies). The sperm move gradually from the testis to the epididymis, an organ that stores and nourishes them as they mature. Once sperm are completely mature, they move into the vas deferens. This tubal structure connects the epididymis with the seminal vesicles, the two pouch-like glands that provide storage for the mature sperm.
The entire process of spermatogenesis from cell division to ejaculation takes about 84 days. Just prior to ejaculation, sperm from the seminal vesicles combine with a thick fluid from the prostate gland to create the semen (a mixture of secretions and sperm), which may then be deposited in the vagina.
The earliest stages of spermatogenesis are easily influenced by fever, prolonged exposure to heat, and chemical exposure. Thus, suboptimal sperm will be ejaculated for two to three months following exposure to these conditions. Likewise, any fertility treatment directed toward the male may take three to four months to become apparent in the semen analysis. Sperm counts drop with frequent ejaculation and may rise with two to seven days of abstinence. Longer periods between ejaculations may result in a drop in sperm quality. Generally, these variations in the quality of semen have no demonstrable effect on the fertile population, but they may contribute to infertility in those having trouble conceiving.
Understanding the fine tuning of the reproductive machine can help you make it work more efficiently for you. Or at the very least it'll help you appreciate the miracle of a healthy pregnancy even more!