For Women
Women who have significant weight gain or extreme weight loss are more likely to not ovulate on a regular basis or at all. An ideal body mass index optimizes regular, ovulatory cycles among women of reproductive age, provided that reproductive hormone tests are in range. Minimizing alcohol intake improves the chances for pregnancy, and in those who smoke cigarettes and/or marijuana, the discontinuation of cigarette smoking and recreational drug use optimizes female fertility as well.
For Men
There are a number of things that men can do to improve their lifestyles and habits to optimize fertility. The majority of lifestyle changes are to avoid environmental factors that can have an adverse impact on sperm. One of the most notorious factors impacting sperm in a bad way is heat. Men are built with the testicles essentially outside of the body in the scrotum for the reason that sperm production is optimized best at a 2-4 degree Celsius cooler temperature than the core body temperature. Primarily, men are advised to avoid heat sources like hot tubs, warm baths, saunas, and laptop computers on the lap. Hot showers and being outside in the heat are considered okay as the body can compensate for those. It is not a bad idea to keep cell phones out of front pockets. Cell phones emit high frequency electromagnetic radiation and there is some data indicating they may affect sperm when they are in such proximity to the testicles in the front pocket, so it is better to keep cell phones in the back pocket or shirt pocket when trying to conceive. Other lifestyle factors that can have a bad affect on sperm include tobacco, alcohol, and marijuana. On the flip side, a healthy diet and exercise tend to optimize male fertility by optimizing muscle to fat ratios, which helps with testosterone to estrogen ratios. Testosterone is converted into estrogen primarily in fat cells, so minimizing body fat helps keep more testosterone as testosterone rather than converting it to more estrogen. Obesity tends to be a risk factor male infertility as lower abdominal and pelvic fat can increase temperatures around the testicles. Men that use anabolic steroids or taking androgen containing supplements for body building will suppress sperm production, and in some men that can have an irreversible impact on sperm production. Avoiding testosterone and testosterone containing products will help keep sperm production going.