Obesity is associated with infertility and a lower pregnancy rate in women undergoing in vitro fertilization (IVF). Women with a very low body mass index (BMI) also are more likely to experience infertility and have a lower likelihood of success with IVF than women whose BMI falls in the normal range.
What factors can impact my fertility?
Body Weight
Obesity is associated with infertility and a lower pregnancy rate in women undergoing in vitro fertilization (IVF). Women with a very low body mass index (BMI) also are more likely to experience infertility and have a lower likelihood of success with IVF than women whose BMI falls in the normal range. In men, obesity is also associated with infertility — sperm count and motility have been shown to be lower in obese men. Weight loss has been shown to improve semen parameters. Erectile dysfunction is more common in obese men. There is no scientific data that supports one diet over another with respect to maximizing fertility.
Exercise
Some data that suggest that moderate exercise, regardless of BMI, is associated with the highest pregnancy rates in women. Daily exercise, however, has been shown to be associated with reduced fertility—especially if the excessive exercise results in menstrual irregularity. Exercise has a similar effect on men—one hour of exercise three times weekly seems to be associated with a higher count, motility, and normal appearing sperm than sperm from men who do not exercise and those who engaged in more frequent/vigorous exercise.
Alcohol Consumption
Extreme alcohol intake has been associated with decreased fertility. What is less clear is the amount of alcohol it takes to negatively impact reproductive function. A review of the literature suggested that four drinks per week is associated with a decreased likelihood of successful IVF in women. Heavy alcohol consumption in men is associated with decreased sperm count, motility, and percent of normal appearing sperm. Some studies have shown a negative impact on sperm with more moderate drinking. Semen parameters have been shown to improve after three months of abstinence from alcohol.
Smoking
There is strong evidence that nicotine negatively effects fertility. It has been suggested that women who smoke add ten years to their reproductive ages—a 30-year-old smoker has the reproductive potential of a 40 year old! Smoking in men negatively impacts sperm quantity and quality and is associated with reduced success with IVF and intra-cytoplasmic sperm injection (ICSI). There is little scientific data on the impact of electronic cigarettes on fertility, but they contain nicotine, so they are likely associated with a decrease in fertility. Ideally, nicotine patches and gum should be avoided.
Recreational Drugs
Studies on the impact of recreational drugs on female fertility are few. Women who use marijuana appear to be more likely to experience infertility. In men, marijuana has been found to increase ejaculation problems and impotence as well as reduce sperm count and motility. Most negative effects from recreational drugs have been shown to be reversed by discontinuing their use.
Cell Phones
In some animal studies evaluating the effect of the radio-frequency electromagnetic radiation (RF-EMR) of cell phones on reproductive function, a negative impact on the ovaries, uterus, and embryo has been identified. Sperm exposed to RF-EMF have decreased motility and are more likely to have an abnormal appearance. The use of cell phones may decrease sperm concentration and motility as well as normal appearance. The abnormalities seemed to be directly related to the amount of use. However, there is no evidence that use of cell phones by women or men is associated with infertility.