Testosterone is an androgen hormone produced by the adrenal cortex, the testes, and the ovaries.

It is often considered the primary sex hormone associated with those assigned male at birth.

Testosterone imbalances can cause infertility in people of any sex.

Man and woman in plank position, man with facial hair and bulkier muscles due to increased testosterone

Westend61 / Getty Images

Low levels of testosteronein cisgender men can cause infertility.

High testosterone levels are associated with infertility in those who can get pregnant.

Testosterone levelscan be evaluated with blood work.

This is usually part of an infertility workup in all genders.

Hormonal Supplementation

Testosterone is a potent steroid hormone whose chemical formulation is C19-H28-O2.

Testosterone is also known as 17-beta-hydroxy-4-androstene-3-one.

Prescription testosterone is used totreat hypogonadism-related conditionsin cisgender men and delayed puberty in cis boys.

Risks of Supplementation

Too much testosterone can cause infertility in any gender.

Warning:Do not attempt to supplement testosterone on your own.

There are a number of websites selling “testosterone supplements,” and many are fake and even dangerous.

Your total testosterone levels include both free and bound testosterone.

Total testosterone levels vary throughout the day.

In cis men younger than 45, levels are highest in the morning and lower toward evening.

Once over the age of 45, it doesn’t matter what time of day levels are checked.

Normal ranges for testosterone partially depend on the lab and a doctor’s interpretation.

With that said, here are some general values.

It is a delicate balance, however.

Both too little and too much testosterone can lead to low sperm counts.

Infants have similar levels of testosterone.

High testosterone levels are also associated with acne in any gender.

Sex drive (libido):The connection between testosterone and sex drive is well known.

Higher levels of testosterone cause higher levels of sexual appetite.

Pain tolerance:Testosterone may help people regulate pain levels.

Learning and memory, especially spatial intelligence:Testosterone aids in learning and memory.

It is especially associated with spatial intelligence.

Cis men with abnormally low testosterone levels are at risk for learning disabilities.

Higher testosterone levels are associated with a lessened ability to read people.

This is true for all genders.

What can cause abnormal testosterone levels?

Summary

Testosterone is an essential hormone for everyone.

If your levels are abnormal, a doctor will likely order more testing to investigate the cause.

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