Toxic effects related to tobacco, marijuana, and other drugs
Smoking may cause infertility in both men and women. In experimental animals, nicotine has been shown to block the production of sperm and decrease the size of male testicles. In women, tobacco changes the cervical mucus, thus affecting the way sperm reach the egg.
Marijuana may disrupt a woman's ovulation cycle, affecting the release of the egg. In men, marijuana use can decrease the sperm count as well as affect the quality of the sperm.
Heroin, cocaine, and crack cocaine use induces similar effects but places the user at increased risk for PID and HIV infection associated with risky sexual behavior.
Stopping fertility treatments -- whether fertility drugs or an assisted reproductive technology -- can be a major issue for couples.
For couples that don't define the ''enough is enough'' point before embarking on the journey to pregnancy, these treatments may become addictive, with each new cycle bringing a flush of optimism. "Just one more cycle and then we'll stop" can go on for longer than the recommended cycle-length of the fertility drugs, and in some cases, for longer than two years --...
In women, the effects of alcohol are related to severe consequences for the fetus. And chronic alcoholism is related to disorders in ovulation, which interferes with fertility. Alcohol use by men interferes with the synthesis of testosterone and has an impact on sperm concentration. Alcoholism may delay a man's sexual response and cause impotence by interfering with a man's ability to have an erection.