As the saying goes, it takes two to tango. This saying applies as much to conception as it does to that dramatic style of dance.

All people, past and present, began with the joining of sperm and an egg. Whether those sperm and eggs belonged to romantic partners, friends, or strangers, at some point, one person had to provide sperm—and the other had to provide an egg.

Guidelines from the American Urological Association (AUA) and the American Society for Reproductive Medicine (ASRM) state that about half of the time, opposite-sex couples don’t conceive after 12 months—because of, or in part because of, the fertility of the male partner.† (1)

If you represent the sperm half of the equation, you likely understand by now that half of the responsibility of trying to conceive falls on your shoulders. We’re here with an overview of what you need to know about preconception health for men, the role of sperm and how to support your pregnant partner when the time comes.

What Are the Hormones Involved in Male Reproduction?

Hormones make conception happen. For men, the hormonal sequence revolves around testosterone (the male sex hormone, T) and follicle-stimulating hormone (FSH). T (produced by the testes) and FSH (produced by the brain’s pituitary gland) are both involved in spermatogenesis, which is sperm’s developmental process, and sperm production. (2)

Understanding the Role of Sperm in Conception

Sperm are one half of the conception puzzle: In order for someone to become pregnant, an egg has to be fertilized by sperm.

Sperm have to meet certain parameters so they can make their way to an ovulated egg (3):
• Sperm count and concentration: There needs to be enough sperm for one to be released in the ejaculate. This means there has to be a good number of sperm overall (sperm count), and the sperm have to be close together so there are some in every ejaculation (concentration).
• Motility: The sperm need to be able to move toward the egg.
• Morphology: The sperm need to be the right shape to fertilize the egg.

When sperm have a good count, concentration, motility, and morphology, they are of the appropriate quantity and quality to travel toward the egg. Sperm quantity and quality, however, can be impacted by a number of genetic, hormonal, environmental, and lifestyle factors (we’ll cover these at length in the next section).

Sperm DNA Fragmentation

One issue with sperm quality is DNA fragmentation. Sperm DNA fragmentation is when there are abnormalities in the sperm’s DNA. These kinds of abnormalities can be caused by factors like heat exposure, smoking, environmental toxins, chemotherapy, and problems in sperm development. Having some degree of DNA fragmentation is expected, but having 20-30% or more damaged sperm can make getting pregnant more difficult.

Testing for sperm DNA fragmentation may be recommended before starting fertility treatment for opposite-sex couples (4).

Obstruction

Aside from sperm quantity and quality, sperm need to be able to leave the testicles and travel through the epididymis (tubes located behind each testicle). There are sometimes barriers in the tubes that block sperm’s path. Sperm obstruction can be caused by repeat infections, vasectomy (the surgical blockage of the tubes), and other developmental defects. (3)

Factors that Affect Male Fertility

Let’s take some time to parse the truths from the myths.

Age

Yes, age does factor into male fertility—just not to the same degree it does among women. Sperm parameters begin to decline at age 35, but significant effects typically don’t show up until around age 50. (5) Still, there isn’t a magic cutoff age for conception for men. (6)

Lifestyle

There are several lifestyle factors that researchers have associated with male reproduction:
• Exercise: According to the AUA and the ASRM, regular resistance and/or high-intensity exercise may be helpful for sperm quality. (10)
• Frequency of penis-in-vagina sex: There’s a stubborn myth that frequent ejaculation can negatively impact fertility. The truth is that daily ejaculation has no adverse effect on male fertility—it may even be helpful for people with oligozoospermia (low sperm count or concentration). Experts recommend having sex every other day during the fertile window (the 5 days before ovulation and the day of ovulation). (5)
• Nutrition: As we’ll unpack more in the next section, certain nutrients may support healthy sperm parameters.* (11)
• Smoking cigarettes: There’s no conclusive scientific evidence that smoking cigarettes negatively impacts male fertility. That said, associated decreases in sperm concentration, motility, and morphology have been observed in research among smokers. (5)
• Worklife: Interestingly, physically demanding and changing-shift jobs may be related to better testicular function. But because the research that observed this phenomenon was conducted in a population of fertility clinic patients, further studies are needed. (12)

Another common misconception? That sex positions impact conception rates. Sperm are so fast they can reach the fallopian tubes and travel to an ovulated egg within minutes. (11)

Environment

Many of the popular myths related to environment and male fertility have yet to be conclusively proven by research. This includes wearing specific kinds of underwear and heat exposure. However, there is evidence supporting the belief that certain environmental toxins—like di-2-ethylhexyl phthalate (a plasticizer) and pesticides (pyrethroids, organophosphates, abamectin)—negatively affect male fertility. Job exposure to oil and natural gas extraction can also have an adverse impact. (1)

Diet to Support Men’s Health

Like with all aspects of health, balanced nutrition has its part in male fertility. The ASRM advises that consuming antioxidants—found in fruits and vegetables, —supports healthy sperm parameters.* (10)

According to a 2018 systematic review and meta-analysis, the following nutrients may also promote sperm health (12):
• Carnitines* (found in beef and other foods )
• Coenzyme Q10 (CoQ10)* (found in oily fish, eggs, nuts, and other foods and supplements)
• Omega-3s* (found in fish, seeds, and other foods)
• Selenium* (found in Brazil nuts, fish, and other foods)
• Zinc* (found in oysters, beef, crab, and other foods)

For All Types of Partnerships

No matter who you are, whether or not you have a partner, and who your partner may be, sperm and an egg (called “gametes” in reproductive medicine) are necessary for having biological children. Different individuals and couples have different paths to conception—and all of them are valid.

For opposite-sex partners, one partner may provide sperm while the other provides the egg. Opposite-sex partners may also use cryopreserved (frozen) gametes, sperm or egg donors, or gestational carriers if they’re unable to, for whatever reason, provide gametes.

For LGBTQ+ couples, one or both partners may not be able to provide the necessary gametes for conception. People in these relationships may also rely on frozen gametes, donors, or gestational carriers, depending on their situation. The same is true when someone decides to have a biological child on their own.

Whatever your path to conception is, if your partner carries a pregnancy, it’s important to be there for them. Whether that looks like sharing articles like the ones in our Journal, having open and honest conversations about the physical and emotional experience, or recommending a pregnancy support group or therapist for one or both of you, showing up for them is a top priority.

†As a health company that adheres to standardized nutrition research—which is often reliant on assigned sex at birth—we face some unique challenges regarding our gender-specific messaging. Our decision to use gendered terms is, unfortunately, a result of these limitations in nutrition research. In cases where complying with the binary distinction is necessary for scientific accuracy purposes, we want to make it very clear that we recognize a person’s gender identity might differ from their assigned sex.

References:

1. Schlegel, P. N., Sigman, M., Collura, B., De Jonge, C. J., Eisenberg, M. L., Lamb, D. J., Mulhall, J. P., Niederberger, C., Sandlow, J. I., Sokol, R. Z., Spandorfer, S. D., Tanrikut, C., Treadwell, J. R., Oristaglio, J. T., & Zini, A. (2021). .. in Men: AUA/ASRM Guideline Part I. The Journal of urology, 205(1), 36–43. https://doi.org/10.1097/JU.0000000000001521
2. O'Donnell L, Stanton P, de Kretser DM. Endocrinology of the Male Reproductive System and Spermatogenesis. [Updated 2017 Jan 11]. In: Feingold KR, Anawalt B, Blackman MR, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279031/
3. Agarwal, A., Majzoub, A., Baskaran, S., Panner Selvam, M. K., Cho, C. L., Henkel, R., Finelli, R., Leisegang, K., Sengupta, P., Barbarosie, C., Parekh, N., Alves, M. G., Ko, E., Arafa, M., Tadros, N., Ramasamy, R., Kavoussi, P., Ambar, R., Kuchakulla, M., Robert, K. A., … Shah, R. (2020). Sperm DNA Fragmentation: A New Guideline for Clinicians. The world journal of men's health, 38(4), 412–471. https://doi.org/10.5534/wjmh.200128
4. Practice Committee of the American Society for Reproductive Medicine and the Practice Committee of the Society for Reproductive Endocrinology …. Electronic address: [email protected] (2022). Optimizing natural fertility: a committee opinion. Fertility and sterility, 117(1), 53–63. https://doi.org/10.1016/j.fertnstert.2021.10.007
5. American Society for Reproductive Medicine. Booklet: Age and Fertility. ReproductiveFacts.org.
6. Agarwal, A., Baskaran, S., Parekh, N., Cho, C. L., Henkel, R., Vij, S., Arafa, M., Panner Selvam, M. K., & Shah, R. (2021). Male ... Lancet (London, England), 397(10271), 319–333. https://doi.org/10.1016/S0140-6736(20)32667-2
7. American Society for Reproductive Medicine. Fact Sheet: Optimizing Male…. 2016.
8. Lidia Mínguez-Alarcón and others, Occupational factors and markers of testicular function among men attending a fertility center, Human Reproduction, Volume 38, Issue 4, April 2023, Pages 529–536, https://doi.org/10.1093/humrep/dead027
9. Salas-Huetos, A., Rosique-Esteban, N., Becerra-Tomás, N., Vizmanos, B., Bulló, M., & Salas-Salvadó, J. (2018). The Effect of Nutrients … on Sperm Quality Parameters: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Advances in nutrition (Bethesda, Md.), 9(6), 833–848. https://doi.org/10.1093/advances/nmy057