By Stella Hye Sung Ryou, MD
Editor’s Note: In honor of Healthy Eating Week, we are delighted to share a summary of Sharma et al.’s “Lifestyle Factors and Reproductive Health: Taking Control of Your Fertility.” This research review, written by Hye Sung (Stella) Ryou during her participation in the FACTS elective, highlights how modifiable lifestyle factors—including nutrition, exercise, stress, smoking, alcohol use, and environmental exposures—can influence reproductive health and fertility outcomes in both men and women. These findings underscore the link between everyday health choices and fertility, a principle central to fertility awareness-based methods (FABMs). To learn more about lifestyle factors and reproductive health, sample our CME from Parts N and O.
Introduction
As many couples struggle with infertility, strategies to reduce its prevalence have become a growing focus. It is well known that lifestyle choices influence health overall, and increasing attention has been given to how these factors affect reproductive health. While some aspects of life are difficult to change, modifiable lifestyle habits that can positively affect fertility have become an area of significant interest.
Methodology
The authors conducted a literature search in Medline to identify studies related to lifestyle factors and reproductive health.[1] The information was compiled, reviewed, and finalized collaboratively by the research team.
Results
Reproductive Timeline:
In men, semen volume and sperm motility begin to decline after age 35, and sperm DNA damage increases after age 40. As paternal age rises, the time required to achieve pregnancy also lengthens. In women, fertility declines more steeply: Those younger than 30 have about a 71% chance of conceiving compared with 41% for women 36 and older. Advanced maternal age also increases the risk of miscarriage due to chromosomal abnormalities. For both sexes, birth rates decrease sharply between ages 35 and 39.
Nutrition:
For men, diets that are high in carbohydrates, fiber, folate, lycopene, fruits, and vegetables and those that are lower in protein and fat are linked to improved fertility. Antioxidants that reduce reactive oxygen species enhance sperm motility and DNA integrity. Large reviews also show that oral antioxidants increase pregnancy and live birth rates. For women, replacing carbohydrates with animal protein raises the risk of ovulatory infertility, however, substituting vegetable protein is protective. Trans fats increase the risk of ovulatory disorders, whereas multivitamin use, iron intake, and high-fat dairy improve fertility outcomes. A fertility-friendly diet includes antioxidant-rich, plant-based foods for men. For women, it includes vegetable protein, monounsaturated fats, multivitamins, and low-glycemic foods.
“For men, diets that are high in carbohydrates, fiber, folate, lycopene, fruits, and vegetables, and those that are lower in protein and fat are linked to improved fertility.”
Obesity:
Obesity negatively affects fertility in both sexes. Obese men are three times more likely to have reduced semen quality with lower sperm concentration and motility, greater DNA damage, and higher rates of erectile dysfunction. Elevated BMI also lowers inhibin B and raises leptin levels, thereby impairing sperm production. In women, obesity increases the risks of miscarriage, chromosomal abnormalities, and lower pregnancy rates. Encouragingly, these effects are reversible, as many women regain ovulation and fertility with weight loss.
Eating Disorders and Underweight:
Being underweight negatively impacts fertility in both sexes. Underweight men tend to have lower sperm concentrations, while underweight women face increased risks of ovulatory infertility, menstrual irregularities, preterm birth, and difficulty sustaining a pregnancy.
Exercise:
Moderate exercise supports fertility, whereas excessive activity can be harmful. Men who exercise moderately (about three times per week) show better sperm morphology and motility, while intense or prolonged exercise reduces sperm quality. In women, more than four hours of vigorous cardiovascular exercise per week decreases live birth rates and increases implantation failure, though moderate activity modestly improves fecundity.
Stress:
Stress and depression reduce testosterone and LH in men, leading to lower sperm count, motility, and morphology. In women, psychological stress prolongs time to conception, but supportive interventions such as cognitive-behavioral therapy or support groups significantly improve pregnancy and live birth rates.
“Stress and depression reduce testosterone and LH in men, leading to lower sperm count, motility, and morphology. In women, psychological stress prolongs time to conception.”
Smoking:
Cigarette smoking impairs fertility in both men and women. In men, it decreases sperm count, motility, and DNA integrity. In women, it lowers ovarian reserve and disrupts tubal function, increasing the risks of ectopic pregnancy and miscarriage.
Illicit Drugs:
Marijuana and cocaine use decrease testosterone levels, spermatogenesis, and sperm quality in men. In women, they disrupt ovulation, implantation, and placental development and increase the risks of infertility and pregnancy complications.
Alcohol:
Excessive alcohol consumption causes testicular atrophy and reduced sperm count in men. In women, heavy drinking delays conception, increases the risk of miscarriage and fetal loss, and causes ovulatory and luteal phase dysfunction.
Caffeine:
High caffeine intake (>100 mg/day) is associated with a higher risk of miscarriage and stillbirth, particularly during the first trimester.
Environmental Exposures:
Air pollution and heavy metals (e.g., lead, mercury) reduce sperm quality and motility in men and increase the risks of miscarriage, stillbirth, preterm delivery, and fetal malformations in women. Occupational exposure to pesticides, solvents, or lead (e.g., in farming, painting, or jewelry-making) has similar effects.
Radiation and Devices:
Radiation from X-rays or cell phones near the groin reduces sperm motility and viability.
Medical Care:
Routine medical and gynecologic visits improve fertility by enabling early disease detection and health counseling, though many men delay seeking care for sexual or reproductive concerns.
Heat and Clothing:
Tight underwear and frequent exposure to heat (e.g., hot tubs, saunas) reduce sperm quality—effects that are reversible with looser clothing and cooler conditions.
Lubricants:
Both commercial and natural lubricants (e.g., oils and saliva) reduce sperm motility and viability, potentially impairing conception.
Discussion
The World Health Organization estimates that 1 in 6 individuals of reproductive age experiences infertility at some point in their lives.[2] Despite this prevalence, awareness of how lifestyle factors affect fertility remains limited. Boivin et al. found that individuals across age groups often lack knowledge about reproductive health and would benefit from broader, evidence-based education.[3] Increasing awareness of modifiable lifestyle factors—such as nutrition, exercise, stress, and environmental exposures—could empower individuals to adopt healthier habits that support long-term fertility.
Sharma et al. emphasized that lifestyle factors play a key role in reproductive outcomes for both men and women.[1] Changes such as improving diet, maintaining a healthy weight, and avoiding smoking and pollutants can make a significant difference. The study provides a comprehensive synthesis of diverse research. However, most included studies were correlational and lacked long-term data, which underscores the need for more research to establish causal relationships and to develop standardized guidelines for effective lifestyle interventions.
“Lifestyle factors play a key role in reproductive outcomes for both men and women. Changes such as improving diet, maintaining a healthy weight, and avoiding smoking and pollutants can make a significant difference.”
Fertility awareness-based methods (FABMs) can also be part of a healthy lifestyle. Beyond helping individuals achieve or avoid pregnancy, these methods promote body awareness in women and allow recognition of hormonal or ovulatory changes. Used as a vital sign of health, they can help identify conditions like PCOS or luteal phase deficiency and empower couples to take an active, collaborative role in their reproductive health journey.
Overall, lifestyle modification is a relatively low-cost, empowering approach to improving fertility and overall health. Expanding fertility education to include lifestyle awareness and charting methods may encourage men and women to take active roles in protecting their reproductive health and well-being.
References
[1] Sharma R, Biedenharn KR, Fedor JM, Agarwal A. Lifestyle factors and reproductive health: taking control of your fertility. Reprod Biol Endocrinol. 2013;11:66. doi:10.1186/1477-7827-11-66.
[2] World Health Organization. Infertility. 2023. Available from: https://www.who.int/news-room/fact-sheets/detail/infertility
[3] Boivin J, Bunting L, Gameiro S. Fertility-related knowledge and perceptions of young adults. Hum Fertil (Camb). 2019;22(3):179–188. doi:10.1080/14647273.2018.1486514.
ABOUT THE AUTHOR
Stella Hye Sung Ryou, MD, is a psychiatry resident at Virginia Commonwealth University Health System and a graduate of Georgetown University School of Medicine. Her clinical and academic interests focus on women’s mental health, reproductive psychiatry, and the connections between lifestyle factors, reproductive health, and psychological well-being. As a participant in the FACTS elective, she explored fertility awareness-based methods and natural family planning to deepen her understanding of reproductive health and its implications for psychiatric care. She aims to integrate this knowledge into her practice to help patients navigate reproductive and mental health decisions with evidence-based support.
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