The Link Between Lifestyle and Fertility
It’s estimated that 188 million people worldwide experience infertility. In some cases, infertility can be influenced by lifestyle factors (very important note: this does not mean that individuals who experience infertility are “at fault” for their infertility, often it can be the result of biological factors). When lifestyle factors (not biological factors) negatively impact fertility, these behaviors can be modified in an effort to enhance fertility and overall well being. Common lifestyle factors include modifiable behaviors like nutrition choices, exercise, self-care in relation to psychological health, substance use, and even the age at which a person chooses to conceive (Sharma et al., 2013). Environmental factors like exposure to toxins and occupational exposures can also impact a person’s fertility. Let’s break it down.
Lifestyle Factors
The age at which a person begins trying for a baby can be a significant factor impacting fertility. Fertility peaks and then decreases over time for everyone, so the reproductive timeline can be a key aspect to consider when determining the ideal time to conceive (Sharma et al., 2013). For women and folks who can get pregnant, fertility declines as the number of oocytes (eggs) decline. The chance of conceiving is highest below the age of 30 at about 71%, and drops to 41% after the age of 35 (Sharma et al., 2013). The decline in fertility is similar for men and people who can impregnate others. As we’ve often discussed in earlier blogs, testosterone decreases with age, and can result in hypogonadism. Hypogonadism occurs when the body’s sex glands do not produce enough testosterone or sperm (U.S. National Library of Medicine, n.d.). Individuals on testorone replacement therapy, a common treatment for hypogonadism, can have increased difficulty conceiving, as testosterone replacement therapy can suppress sperm production. On average, semen volume and motility also begins to decline around age 35, with significant declines after the age of 40 (Sharma et al., 2013).
Nutrition can also influence fertility. Certain vitamins, minerals, and macronutrients can negatively impact a person’s fertility. Decreasing the amount of proteins and fats consumed has been shown to have a positive impact on fertility (Sharma et al., 2013). For men and people who can impregnate others, research indicates a correlation between a diet rich in carbohydrates, folate, fruits, and vegetables and improved semen quality (Sharma et al., 2013).
Exercise and physical activity can have a protective effect on fertility for folks who can get pregnant, provided the exercise is not exceptionally strenuous or excessive. When exercise is too strenuous and energy output overtakes ones energy input from food, it can cause menstrual abnormalities and increased strain on the body which will make it more difficult to conceive (Sharma et al., 2013). For men and people who can impregnate others, regular physical activity (typically one hour of moderate exercise three times per week in studies) has been shown to support sperm count (Sharma et al., 2013). Similarly, mental stress can negatively impact an individual’s fertility, highlighting the importance of supporting one’s mental health when trying to conceive a child.
Substance use, from alcohol and cigarettes to prescription/illicit drugs can also influence fertility. While research indicates that individuals who smoke have higher ratios of infertility compared to non-smokers, more research is needed to fully establish a link between cigarette smoking and decreased fertility. Illicit drugs may influence fertility, but research is scarce due to ethical considerations. Certain prescription drugs can negatively affect fertility, particularly for women and people who can conceive. Drugs like metoclopramide or amatryptaline raise prolactin levels, which can impact ovulation and make it more difficult to conceive.
Reference
Sharma, R., Biedenharn, K. R., Fedor, J. M., & Agarwal, A. (2013). Lifestyle factors and reproductive health: taking control of your fertility. Reproductive biology and endocrinology : RB&E, 11, 66. https://doi.org/10.1186/1477-7827-11-66
U.S. National Library of Medicine. (n.d.). Hypogonadism: Medlineplus medical encyclopedia. MedlinePlus. Retrieved February 24, 2023, from https://medlineplus.gov/ency/article/001195.htm