See collections

Last revised:

Your sperm questions, answered

If I do a semen analysis, will it come back stamped “FERTILE” or “INFERTILE”?

Nope. Fertility isn’t a binary, and infertility would only be diagnosed after 6–12 months of actively trying to have a baby without luck. A semen analysis will give you a set of metrics about your sperm that correlate to the chances you’ll be able to have a child without medical assistance.

Are there things I can do to improve my fertility, or is it simply the hand I was dealt?

Issues with sperm health are typically — in the overwhelming majority of cases — treatable. Male fertility is highly influenced by lifestyle and hormone health, so addressing those contributing factors can measurably improve your sperm parameters.

How long it will take to improve sperm health depends on what’s the underlying cause. It takes 72 days to produce new sperm, so if you’re making a lifestyle change, we recommend giving it at least 3 months before you can expect to see the results in your sperm.

That being said, sperm quality does decline a bit each year — so freezing now is one way to ensure you can use your “peak sperm” for years to come.

How does testosterone impact sperm health?

The relationship between testosterone and sperm is a bit complex. Testosterone plays an essential role in sperm production. However, even men with low T can produce normal sperm counts.

Boosting your testosterone levels doesn’t translate to increased fertility. In fact, the opposite is true. Using exogenous (external) testosterone will disrupt the hormone balance and actually halt sperm production. Research has found that using testosterone can bring sperm count to zero in just 4–6 months.

How does sperm connect more broadly to my overall health?

Since 2022, experts have recognized sperm quality as both a biomarker for present health and a predictive tool for future health risks.

For example, men with low sperm concentration and low sperm motility have a 200–300% higher chance of testicular cancer than men with normal sperm parameters (1, 2, 3). Low sperm count and low sperm motility are correlated with a 40% higher risk for cardiovascular disease.

Is it true that Mountain Dew affects sperm health?

Kinda. A 20-ounce bottle of Mountain Dew has a whopping 77 grams of added sugar. Research has found a strong correlation between overall sugar intake and poor sperm motility, so maybe there is some truth to this urban legend.

When will I reach “peak sperm”?

Most studies have found that sperm quality is highest before age 35. Researchers have found a significant decline in sperm genetic health (i.e. the quality of the DNA carried by sperm) and sperm motility from your 30s to your 40s and beyond. Men over 35 are less likely to create a healthy pregnancy.

Your lifestyle can also impact when you achieve your personal “peak sperm.” For example, smoking cigarettes damages sperm quality; if you smoked through your 20s, your sperm health will be higher after you quit in your 30s. But the impact of age underlies any other influences.

How does sperm quality relate to pregnancy complications?

Sperm quality has a surprising influence on how healthy a pregnancy may be.

High levels of sperm DNA fragmentation (AKA damage to the DNA carried by sperm) increase the risk of miscarriage to almost double. Researchers have hypothesized that sperm quality is an important contributor to cases of recurrent miscarriage.

Partners of older men (who have lower sperm quality) are more likely to experience preterm birth and even gestational diabetes.

How does sperm quality relate to the health of the baby?

As discussed, sperm quality and genetic health declines with age. That is the primary reason why children of older fathers are more likely to experience mental and physical health issues.

  • Older fathers are more likely to have children with birth defects.
  • Paternal age is associated with a significantly increased risk for autism, likely due to the accumulation of genetic mutations within sperm.
  • There is a strong correlation between a father’s age and his child’s risk of schizophrenia.

There’s also research to suggest that sperm quality influences a child’s health regardless of paternal age. For example, high levels of sperm DNA fragmentation caused by smoking has been identified as a factor in childhood cancer.

Is young frozen sperm better than old fresh sperm?

Generally speaking, yes. As discussed above, sperm quality decreases over time. Once frozen, sperm quality does not decline due to age.

But does the freezing process damage sperm? Studies have shown that 74–85% of sperm will survive the process of freezing and thawing; the sample that remains will have a slight decline in motility. However, multiple large analyses have found that frozen sperm is just as likely to result in a pregnancy as a “fresh,” never-frozen sperm.

What’s the “expiration date” on frozen sperm?

Thankfully, this isn’t like that package of hot dogs you forgot in the back of your freezer. As long as sperm are frozen properly in a high quality cryogenic facility, they can be stored indefinitely.

A 2019 study published in Fertility and Sterility looked at the results of 119,558 frozen semen specimens. They found that using frozen sperm stored for up to 15 years had no impact on the rates of pregnancies, miscarriages, or live births (compared to using fresh sperm).

Sperm frozen for 40 years has been used to create healthy babies. So rest assured — you’ve got some time here.

How does the sperm retrieval process work at Legacy?

As a Legacy client, you have a digital dashboard where you can see your results and the lowdown on any samples in long-term storage.

If you’d like to withdraw some or all of your sperm to use in a fertility treatment, you can simply request a vial withdrawal from your client dashboard to get the process started. There, you’ll provide us with details about your healthcare provider, and we’ll coordinate directly with them to facilitate the transfer and proper processing of your frozen sample.

Get started today!

Explore more collections