What Can Harm Your Chances of Getting Pregnant?
Written by Leann Poston, M.D.
What Is Fertility?
Fertility is the natural ability to conceive a child. It involves the endocrine, reproductive, and nervous systems in both men and women, at a minimum. In addition, many lifestyle factors can positively or negatively impact fertility. About 9% of men and 11% of women of reproductive age in the U.S. have experienced fertility problems (NIH, 2017).
The following steps are necessary for a pregnancy to occur:
- The male must produce normal, healthy sperm
- The male must be able to ejaculate the sperm
- The female must be able to ovulate an egg from the ovary
- The sperm must be able to fertilize the egg
- The egg must be able to implant in a prepared uterus (Goldman & Schafer, 2015)
What are the signs and symptoms of infertility?
Infertility is exacerbated by hormonal imbalances, inherited conditions, and advancing age. Fertility in females peaks in the mid-20s and declines after age 35. In men, fertility decreases with age but not as quickly as in women.
In many cases, despite a thorough examination, no cause of infertility is discovered. Because many factors can contribute to infertility, it’s important to recognize warning signs. The following signs may indicate a fertility issue:
- Being under the age of 35 and having unprotected sexual intercourse for a year without becoming pregnant
- Being over age 35 and unsuccessful at getting pregnant after trying for six months
- Having two or more successive pregnancy losses
- Having risk factors for infertility
The most common symptoms of a problem with fertility include:
- Pelvic pain or pain during intercourse
- Unusually heavy or light periods or abnormal menstrual bleeding
- Irregular menstrual cycles
- Menstrual cycles that are less than 24 days or more than 35 days
- Severe menstrual cramps
- Erectile dysfunction
- Low libido
Irregular menstrual cycles may be a sign of polycystic ovarian syndrome. It can also signal hormonal issues such as abnormal thyroid hormone levels. Menstrual cramps that are severe enough to interfere with your daily activities, especially with irregular periods, may be a sign of endometriosis. Low testosterone levels can cause male infertility. Each hormone must be at optimal levels, or symptoms may result.
Overall, about 8% of infertility is caused by male reproductive issues, and in about 35% of cases, both male and female factors contribute to infertility (CDC, 2021). After an evaluation by your doctor for both you and your partner, consider changes you can make that may tweak your hormone levels just enough to get pregnant. There are lifestyle changes you can make to maximize the chances that your hormones are at optimal levels.
Physical Issues That Cause Fertility Problems
For women, an infertility workup usually includes evaluating the fallopian tubes to ensure they are patent and ovarian reserve testing.
- Sexually transmitted diseases: Untreated STDs such as gonorrhea and chlamydia can cause scarring of the fallopian tubes, which can block the microscopically thin channel that connects the ovaries and the uterus.
- Uterine abnormalities: Fibroids or benign smooth muscle tumors can affect implantation, as can uterine or cervical polyps. Polyps are noncancerous growths on the uterus or cervix.
- Early menopause: Early menopause, defined as before age 40, means that you are no longer ovulating. Each woman is born with her lifetime supply of eggs, and the number declines over time. Menopause occurs when the number of functioning eggs falls below a certain threshold.
- Hormonal Imbalances: Polycystic ovarian syndrome, high prolactin levels, and thyroid problems can all cause difficulties with ovulation. Women with polycystic ovarian syndrome have elevated levels of testosterone. Symptoms include excess hair growth and acne.
- Functional hypothalamic amenorrhea: Fat (adipose) tissue produces estrogen in both men and women. When adipose tissue as a percent of body weight falls too low, estrogen levels drop, and a woman does not ovulate. Excessive exercise, weight loss, stress, and eating disorders may cause infertility (Nelson & Bulun, 2001).
- Endometriosis: The lining of the uterus is sensitive to estrogen and progesterone levels. It thickens and sheds in response to changing hormone levels. With endometriosis, these cells are found outside of the uterus. Endometriosis can cause scarring and adhesions that can obstruct the egg in its path from the ovary to the uterus.
An infertility workup for men typically starts with a semen analysis to evaluate the number of sperm, their motility, and shape.
- Varicose veins: Swollen blood vessels near the testes increase their temperature. The excess heat may affect the number and shape of sperm. The testes should be two degrees cooler than the core body temperature.
- Infections: Sexually transmitted diseases may decrease fertility.
- Trauma: Trauma to the testes may affect sperm production.
- Endocrine: Increase production of prolactin can affect sperm production.
- Inherited Conditions: Kleinfelter’s syndrome and other genetic conditions can cause little or no sperm production.
- Erectile dysfunction: Many men experience erectile dysfunction or the inability to get or sustain an erection suitable for sexual intercourse.
Lifestyle Choices That Hurt Fertility Chances
Lifestyle choices can affect fertility. Sometimes the effect is slight but additive. The Pregnancy Study Online (PRESTO) by BU School of Public Health explores many of these lifestyle factors and has published studies on their results.
- Smoking: High cumulative exposure to cigarette smoke is associated with decreased fertility in both current and former smokers compared to women who have never smoked (Radin et al., 2014).
- Drugs and Alcohol: Excessive alcohol intake can affect hormone levels, weight, and fertility. Drug use affects blood flow and blood pressure, which can also cause infertility. The inability to do controlled human studies on drugs and alcohol usage limits the conclusions researchers can make (Sansone et al., 2018).
- Diet: Diet, especially high intake of sugar-sweetened beverages and caffeine, may affect fertility. Caffeine can affect ovulation and menstruation in females and sperm quality in males (Wesselink et al., 2016). Women in one study who were attempting to conceive and ate diets with foods that significantly impacted blood sugar levels, had a high carbohydrate to fiber ratio and added sugar, experienced lower fertility rates (Willis et al., 2020).
- Exercise: Strenuous physical labor can reduce sperm count in men (NIH, 2015). Physical activity can reduce fertility in women who have a BMI below 25 kg/m2. Moderate physical activity was associated with increased fertility (Wise et al., 2012).
- Weight: Obesity is linked to lower sperm count and quality in men. Twelve percent of infertility cases are due to women weighing too much or too little.
- Stress: Dealing with infertility undoubtedly causes stress. Whether stress causes infertility has been debated and explored in many clinical trials (Rooney et al., 2018). Men and women experiencing infertility have high stress levels, which can affect their home and work lives. The interplay between stress and health conditions is complex. Any interventions to decrease stress are likely to positively impact overall health and potentially fertility.
Read The Surprising Link Between Sex and Work Productivity to learn more about what researchers found.
The medications used to treat infertility can cause anxiety and even depression. Dealing with your emotions while being treated for infertility, as well as the overall stress of dealing with infertility, can cause anxiety and depression that can significantly affect your mental health.
Read The Connection Between Intimacy and Mental Health to learn more.
- Environmental Toxins: Environmental toxins such as pesticides, lead, cadmium, and mercury may increase the risk of male infertility.
- Exposure to heat: Heat from a laptop, a sauna, or a hot tub may affect the number and shape of sperm.
Promoting Your Fertility
For both men and women, maintaining a healthy weight, moderate exercise, and a healthy diet support overall health and fertility.
- Maintain a healthy weight as both extremes of weight are associated with an increased risk of infertility.
- Limit alcohol consumption and stop smoking (if applicable).
- If your doctor advises, take a prenatal vitamin to provide the nutrients you need including vitamins A & D, iron, B6, and B 12.
- See your dentist. Poor oral health can negatively impact pregnancy.
- Time intercourse to correspond with ovulation.
- Eat a healthy diet high in antioxidants. Eat fiber, avoid processed foods and trans fats and consider replacing animal protein sources with plant-based (Chavarro et al., 2008).
- Moderate exercise can reduce the risk of infertility and improve sperm quality.
- Limit alcohol intake.
- Time intercourse to correspond with ovulation. Every other day allows time for sperm maturation.
- Avoid lubricants that contain spermicides or affect sperm motility.
- Eat a healthy diet high in antioxidants.
- Treat erectile dysfunction.
While we strive to always provide accurate, current, and safe advice in all of our articles and guides, it’s important to stress that they are no substitute for medical advice from a doctor or healthcare provider. You should always consult a practicing professional who can diagnose your specific case. The content we’ve included in this guide is merely meant to be informational and does not constitute medical advice.
- Goldman, L., & Schafer, A. I. (2015). Goldman-Cecil Medicine (25th ed.). Elsevier.
- Centers for Disease Control and Prevention (2021). Infertility FAQs. Retrieved from http://www.cdc.gov/reproductivehealth/infertility
- Nelson, L. R., & Bulun, S. E. (2001). Estrogen production and action. Journal of the American Academy of Dermatology, 45(3 Suppl), S116–S124. https://doi.org/10.1067/mjd.2001.117432
- National Institutes of Health. Eunice Kennedy Shriver National Institute of Child Health and Human Development. (2017, January 31). Infertility and Fertility. Retrieved from https://www.nichd.nih.gov/health/topics/infertility
- Physical labor, hypertension and multiple meds may reduce male fertility. (n.d.). Retrieved June 9, 2021, from Nih.gov website: https://www.nichd.nih.gov/newsroom/releases/030915-male-fertility
- Wesselink, A. K., Wise, L. A., Rothman, K. J., Hahn, K. A., Mikkelsen, E. M., Mahalingaiah, S., & Hatch, E. E. (2016). Caffeine and caffeinated beverage consumption and fecundability in a preconception cohort. Reproductive toxicology (Elmsford, N.Y.), 62, 39–45. https://doi.org/10.1016/j.reprotox.2016.04.022
- Wise LA, Rothman KJ, Mikkelsen EM, Sørensnen HT, Riis AH, Hatch EE. A prospective cohort study of physical activity and time to pregnancy. Fertil Steril 2012; 97(5): 1136-42.
- Radin RG, Hatch EE, Rothman KJ, Mikkelsen EM, Sørensen HT, Riis AH, Wise LA. Active and passive smoking and fecundability in Danish pregnancy planners. Fertil Steril 2014; 102(1): 183-191.
- Hahn KA, Wesselink AK, Wise LA, Mikkelsen EM, Cueto HT, Tucker KL, Vinceti M, Rothman KJ, Sørensen HT, Hatch EE. Iron consumption is not consistently associated with fecundability among North American and Danish pregnancy planners. J Nutr 2019; 149(9): 1585-1595.
- Willis SK, Wise LA, Wesselink AK, Rothman KJ, Mikkelsen EM, Tucker KL, Trolle E, Hatch EE. Glycemic load, dietary fiber, and added sugar and fecundability in 2 preconception cohorts. Am J Clin Nutr 2020; 112(1): 27-38.
- Rooney, K. L., & Domar, A. D. (2018). The relationship between stress and infertility. Dialogues in clinical neuroscience, 20(1), 41–47. https://doi.org/10.31887/DCNS.2018.20.1/klrooney
- Chavarro, J. E., Rich-Edwards, J. W., Rosner, B. A., & Willett, W. C. (2008). Protein intake and ovulatory infertility. American journal of obstetrics and gynecology, 198(2), 210.e1–210.e2107. https://doi.org/10.1016/j.ajog.2007.06.057
- Sansone, A., Di Dato, C., de Angelis, C., Menafra, D., Pozza, C., Pivonello, R., Isidori, A., & Gianfrilli, D. (2018). Smoke, alcohol and drug addiction and male fertility. Reproductive biology and endocrinology : RB&E, 16(1), 3. https://doi.org/10.1186/s12958-018-0320-7