From testosterone to FSH and LH, a number of hormones drive male fertility. These chemical messengers regulate sperm production, sex drive, and more. Imbalances have the potential to contribute fertility issues.
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Key Takeaways:
From testosterone to FSH and LH, a number of hormones drive male fertility. These chemical messengers regulate sperm production, sex drive, and more. Imbalances have the potential to contribute fertility issues.
Hormonal imbalances are treatable. While conditions like low testosterone, high estrogen, thyroid dysfunction, or elevated prolactin can all interfere with fertility, many can be managed with lifestyle changes or medications.
Testing is crucial. If pregnancy hasn’t occurred after 12 months of regular unprotected intercourse, or after 6 months if the female partner is older than 35 or either partner has known risk factors, see a clinician. Hormone testing can help pinpoint the root cause and guide treatment.
The relationship between certain male hormones and fertility is strong: Even minor imbalances of these key hormones can have a major impact on reproductive health.
For one example to illustrate how this works, consider that a man continuously produces vast numbers of sperm all thanks to hormonal signals between the brain and the testes. When the signals are disrupted, sperm production and overall fertility can take a serious hit.
Ahead, we’ll break down the key hormones that influence male fertility, what happens when these heavy hitters get out of balance, and the steps men can take to restore hormonal health to improve their chances of conceiving.
Male fertility refers to a man’s ability to help achieve pregnancy with a female partner. Male infertility, on the other hand, is a man’s inability to conceive after one year of unprotected sex during a female’s ovulation window.
Healthy male fertility requires:
Healthy sperm production
Effective transport of the sperm
Delivery of sperm into the female reproductive tract
Research estimates that male reproductive issues cause 30–50 percent of infertility cases (alone or combined). Female factors and combined or unknown causes make up the remainder. Given this data, it’s important for men to understand the connection between male hormones and fertility.
Hormones are chemical messengers that the endocrine system secretes. They control various bodily processes, including metabolism, mood, body temperature, and muscle growth. The endocrine system is also the prime regulator of reproductive health — here’s how it works:
Hormones travel through the bloodstream to target tissues within the male reproductive system. This process prompts the development of male sex characteristics, regulating the libido, and controlling sperm production and maturation.
While fertility issues can arise from hormone imbalances, it’s important to note that disorders of the hormone-producing glands (endocrinopathies), like diabetes or hypothyroidism, only account for about 1 to 2 percent of male infertility cases. Other potential causes of male infertility include testicular or ejaculatory dysfunction and genetic disorders.
According to the Centers for Disease Control and Prevention (CDC), common risk factors for male infertility include:
Age (being over 40)
Excessive drinking
Smoking
Having overweight or obesity
Exposure to environmental toxins or radiation
Testicular injury or exposure to high temperatures
An area of the brain called the hypothalamus produces gonadotropin-releasing hormone (GnRH). It signals the small but mighty pituitary gland to release other essential reproductive hormones (gonadotropins), including follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
The brain releases GnRH in pulses. Disruption to the precise pattern can have a domino effect that compromises other components of healthy hormone functioning, including testosterone output and sperm development.
The 101 on GnRH imbalances:
Too little GnRH (often from issues in the hypothalamus or pituitary tumors) can cause low levels of FSH and LH, which can then lead to low testosterone, poor sperm production, decreased libido, and sometimes infertility. When low testosterone is a result of an issue from the pituitary gland or hypothalamus, it’s called secondary hypogonadism.
Causes include genetic conditions (like Kallmann syndrome), head trauma, use of certain drugs like glucocorticoids and chemotherapy, and malnutrition.
Though uncommon, high GnRH in men may occur when testosterone is too low from primary testicular failure. Research shows that normally, testosterone signals the brain to dial back GnRH. When levels drop, the brain increases GnRH to nudge the pituitary to release more LH and FSH.
This can be the body’s way of protecting fertility, but if the testicles can’t respond, infertility may still occur. In medical treatments, drugs that mimic GnRH may briefly boost hormone activity, but long-term use can actually shut down testosterone and sperm production.
The pituitary gland produces follicle-stimulating hormone (FSH), which is a gonadotropin. In men, FSH stimulates the Sertoli cells in the testes to develop sperm.
The 101 on FSH imbalances:
High FSH levels usually signal that the testes aren’t responding appropriately (primary hypogonadism). Less commonly, high FSH can mean that a pituitary tumor is overproducing hormones.
Low FSH suggests hypothalamic/pituitary dysfunction (secondary hypogonadism).
Some causes of FSH imbalances include genetic issues like Klinefelter syndrome, testicular injury, cancer treatments, alcohol abuse, or pituitary tumors.
The pituitary gland also produces luteinizing hormone (LH), a gonadotropin that supports fertility by signaling the Leydig cells in the testes to produce testosterone, the primary male sex hormone. Like FSH imbalances, LH imbalances can also signal male hypogonadism and contribute to infertility.
The 101 on LH imbalances:
Low LH often points to pituitary or hypothalamic dysfunction (secondary hypogonadism). Causes can include genetic conditions like Kallman syndrome, pituitary disorders, obesity, HIV, and stress-induced hypogonadism.
High LH with low testosterone indicates primary hypogonadism. In this case, the testes themselves are struggling (primary hypogonadism), as seen in conditions like Klinefelter syndrome, testicular damage, undescended testicles, mumps orchitis, cancer treatments, and normal aging.
Testosterone is the primary male sex hormone (androgen). Leydig cells in the testes are largely responsible for testosterone production. The hormone is vital for the development of male secondary sex characteristics, sex drive, bone density, muscle mass, and energy levels. Testosterone is also essential for sperm production and healthy sexual function.
The 101 on testosterone imbalances:
Low testosterone, or male hypogonadism, is one of the most common hormonal causes of infertility. It can contribute to reduced sperm count, poor sperm quality, erectile dysfunction (ED), and low sex drive. Low T can also impact energy levels, mood, and body composition.
Causes of low testosterone depend on whether the form of low T is primary or secondary. Potential causes of primary low testosterone may include genetic conditions and testicular injury. Secondary causes may be pituitary disorders or head trauma. More common factors — such as obesity, chronic illness, poor lifestyle habits, certain medications, and even excessive alcohol or drug use — can also drive low T.
High testosterone can also cause issues, but the effects depend on where the problem originates. Using supplemental testosterone, like testosterone replacement therapy (TRT) or anabolic steroid use, can trick the brain into thinking the testicles don’t need to work, in turn shutting down sperm production and potentially leading to male infertility.
Naturally higher androgen levels, on the other hand, don’t usually cause infertility, since the body’s feedback system keeps hormone balance in check. Instead, this form of high T may show up as visible changes like acne, oily skin, or male-pattern hair loss, especially if free testosterone or DHT is elevated.
Estrogen (specifically its most potent form, estradiol) isn’t just a female thing. The hormone is also present in men and plays a role in male reproductive health. Made in small amounts from testosterone, it supports bone health, regulates sex drive, and helps sperm mature.
The 101 on estrogen imbalances:
High estrogen levels in men can suppress LH and FSH, lower testosterone, and impair spermatogenesis. Some men may experience breast tissue enlargement (gynecomastia). Causes include certain tumors or medications, obesity-related aromatization, and possible environmental estrogenic exposures.Low estrogen levels are rare but typically linked to genetic conditions such as aromatase deficiency or estrogen resistance. Research shows low estrogen may cause sperm abnormalities, impaired motility, or testicular development issues, though not every man with low estrogen is infertile.
Prolactin plays a key role in lactation in women and is also essential to male reproductive health. In men, prolactin levels are typically low. When levels are elevated, they can suppress the hypothalamic-pituitary-gonadal axis.
The 101 on prolactin imbalances:
Hyperprolactinemia, or abnormally high prolactin levels. It can reduce libido, contribute to ED, and lead to fertility issues. Common causes include prolactin-raising medications and pituitary adenomas. Physiologic stress and intense exercise can cause transient elevations.
Low prolactin is less studied but may have links to sexual dysfunction and ejaculatory disorders, which can make conceiving more difficult. Research suggests that low prolactin may not directly damage sperm but instead reflects other underlying issues, such as neurotransmitter imbalances, metabolic problems (like diabetes or poor diet), or the effects of dopaminergic medications.
The pituitary gland produces thyroid-stimulating hormone, which regulates the thyroid’s production of thyroxine (T4) and triiodothyronine (T3). These thyroid hormones influence metabolism, energy, and body temperature, and they also play an important supporting role in male fertility. Thyroid hormone imbalances can impact testosterone production, sperm development, and overall reproductive function.
The 101 on thyroid imbalances:
Hypothyroidism, or underactive thyroid, can cause low levels of sex hormone–binding globulin (SHBG), LH, FSH, and testosterone. This can impair semen quality and sexual function.
Hyperthyroidism, or overactive thyroid, can also lower sperm count and quality, potentially leading to infertility.
Potential causes of abnormal TSH levels include autoimmune thyroid disease (such as Hashimoto’s thyroiditis or Graves’ disease), iodine deficiency or excess, smoking, and stress.
Hormonal disruptions don’t just affect fertility. They can also show up in your everyday life as weight gain, sexual dysfunction, low energy levels, and more.
Signs and symptoms of hormonal imbalances may include:
Weight gain or difficulty losing weight
Low sex drive
Fatigue
Mood changes such as depression, anxiety, or irritability
Loss of muscle mass and increased body fat
Hair loss or reduced body hair
Breast growth
Difficulty conceiving
Recognizing these patterns can prompt earlier testing and treatment.
A comprehensive hormonal assessment involves bloodwork to measure key biomarkers. Key blood tests can help pinpoint whether a hormonal imbalance originates in the testes, brain, or other endocrine glands:
Total testosterone and free testosterone. Measure overall and unbound (biologically active) testosterone levels. Total testosterone measurements typically occur on two separate mornings.
Luteinizing hormone (LH). Assesses pituitary function and testicular response.
Follicle-stimulating hormone (FSH). Evaluates pituitary signals and sperm production.
Prolactin. Checks for hyperprolactinemia or hypoprolactinemia.
Estradiol. Measures estrogen levels to detect potential excess or deficiency.
Sex hormone-binding globulin (SHBG). Helps interpret total testosterone levels by indicating how much is unbound to proteins.
Thyroid hormones (TSH, T3, and T4). Check for hypo- or hyperthyroidism.
Micronutrients. Checks micronutrient deficiencies linked to male subfertility, like low levels of vitamins C, E, zinc, folic acid, and others.
These tests typically take place in the morning when the relevant fertility hormone levels are highest.
Talk to a healthcare provider and consider hormone testing if you are experiencing:
Difficulty conceiving after one year of unprotected sex.
Low libido or erectile dysfunction.
Fatigue, depression, or mood changes that might indicate hormonal issues.
Reduced muscle mass or increased body fat.
Abnormal semen analysis results, such as low sperm count or poor sperm motility.
Specialists who typically evaluate hormonal causes of infertility include urologists with expertise in male fertility and endocrinologists, who focus on hormone-related conditions. However, you can also consider at-home lab tasting.
No matter what kind of hormonal imbalance you have, making healthy lifestyle tweaks can be a helpful first step in restoring balance. However, implementing lifestyle changes does not replace the importance of seeking the care of a healthcare provider:
Maintain a healthy weight. Obesity can increase estrogen levels and decrease testosterone.
Exercise regularly. Appropriate amounts of exercise positively impact hormone production and make tissues more sensitive to hormones.
Clean up your diet. Focus on consuming whole foods that are rich in antioxidants and essential nutrients. If you have a limited diet or vitamin deficiencies, consider taking supplements.
Keep your stress levels in check. Chronic stress can disrupt the HPG axis. Take action to lower your stress levels, like by practicing mindfulness meditation, getting enough sleep, or considering talk therapy.
Limit substances. Drinking too much, taking drugs, and smoking can all negatively impact hormone levels, sperm quality, and overall health.
Talk to your healthcare provider about what treatments are available for your specific hormone imbalance.
For example, if you have low testosterone and want to conceive, testosterone replacement therapy (TRT) might not the best treatment option, as it could further compromise fertility by suppressing sperm production. However, alternative medications like enclomiphene citrate and clomiphene citrate may help increase your body’s natural testosterone production without negatively affecting fertility.
Find out more about how enclomiphene works and how enclomiphene supports fertility.
When hormonal treatments don’t work, fertility treatments and assisted reproductive technologies can offer solutions:
Intrauterine insemination (IUI): Places processed sperm into the uterus to improve the chance of fertilization
In vitro fertilization (IVF): Involves fertilizing eggs with sperm in a laboratory setting, then transferring the embryos to the uterus for implantation.
Intracytoplasmic sperm injection (ICSI): A single sperm is injected directly into a mature egg, often used in cases of severe male factor infertility.
For women, IVF typically involves stimulating ovarian function to retrieve eggs. For men, IVF often aims to correct hormonal imbalances that affect sperm production.
ART bypasses many male-factor barriers (sperm count, motility, morphology, and transport). It does not correct male hormonal imbalances, which are managed separately with medical therapy. Talk to a fertility specialist to see if they can help.
Without your hormones, most of your body would be in serious trouble, including your sexual and reproductive function. Understanding the role these hormones play and the impact of imbalances is crucial if you happen to be facing fertility issues.
Talk with a healthcare professional to see if you’re a good candidate for hormone testing and discuss which treatments are available. Addressing hormonal imbalances today can significantly improve your chances of becoming a parent in the future.
In many cases, you can manage or potentially reverse hormonal imbalances with appropriate treatment and lifestyle changes.
The timeline varies depending on the specific imbalance and treatment. But due to the sperm production cycle, improvements in sperm parameters often take three to six months.
Doctor-prescribed hormonal treatments are generally safe, but you should discuss potential side effects with your provider.
Not exactly. Men don’t experience menopause. Many men develop age-related testosterone decline, which can affect energy, sexual function, body composition, and semen parameters. This change is gradual and variable, unlike the abrupt ovarian cessation in menopause.
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