If you’re a man trying to conceive with your partner, you may worry about how a fever might affect your fertility. High temperatures are generally considered anything above 99 or 100 degrees Fahrenheit, while the average body temperature is around 98.6 degrees Fahrenheit.
The testicles function best at a temperature that’s a few degrees cooler than the rest of the body. That’s why they’re located outside the body. Even a slight increase in temperature can potentially affect sperm production and quality.
But can a fever really kill sperm? And if so, what does that mean for your fertility? And what can you do to recover? This article will explore the effects of fever on sperm health and provide guidance on when to seek medical advice. We’ll cover what to expect and how long it might take for your sperm to recover.
Understanding the Basics: Fever and Spermatogenesis
To understand how a fever could affect sperm, it’s important to know a few key things about fevers and how sperm are produced.
What is a Fever?
A fever is a temporary increase in your body temperature, often due to an illness. You might get a fever because of an infection, inflammation, or even a reaction to a medication.
How Body Heat Affects Sperm Production
The ideal temperature for sperm production is around 93.2ºF (34ºC). That’s why the testicles are located outside the body in the scrotum — to keep them a little cooler than your core body temperature.
When the scrotum gets too warm — like when you have a fever — it can impair sperm production, lowering both the sperm count and the sperm quality.
Research shows that even a mild rise in testicular temperature can significantly increase abnormalities in sperm DNA and decrease normal sperm shape (morphology).
The Impact of Fever on Sperm Quality Parameters
So, what happens to sperm when a man has a fever? Turns out, a fever can impact several key measures of sperm health.
Fever and Sperm Count
A prolonged fever — especially one lasting several days with temperatures above 101°F — can really take a toll on sperm concentration, which is the amount of sperm in a given sample.
Statistics show the potential impact:
- Sperm concentration can drop by as much as 7% within 6 weeks after a fever of 102.2°F or higher that lasts for 3 days or more.
- One study indicated that sperm concentration can decrease by up to 8.5% for each day someone experiences a fever.
- Another study showed that men who had a febrile illness experienced a 32–35% decrease in sperm concentration.
Fever and Sperm Motility
Sperm motility, or the ability of sperm to swim correctly, can also take a hit after a fever, sometimes for weeks.
- One study showed that progressive motility (how well sperm swim forward) can decrease by as much as 23% around 6 weeks after a fever.
Fever and Sperm Morphology
Sperm morphology refers to the shape of the sperm. Healthy sperm have a specific shape that allows them to swim efficiently and fertilize an egg. A fever can also impact sperm morphology.
- Studies have shown a greater than 7% decrease in the number of sperm that are considered morphologically normal after a fever.
Fever and Sperm DNA Fragmentation
Sperm DNA fragmentation refers to damage to the sperm’s genetic material. This damage can affect fertilization and embryo development. A fever can also increase sperm DNA fragmentation.
- One study found that 36% of sperm had damaged DNA 18 days after a man experienced a flu fever for just one day.
Recovery and Semen Analysis: What to Expect
How Long Will It Take My Sperm to Recover from a Fever?
Good news: The effects of a fever on sperm are generally reversible. Once your body temperature returns to normal, your sperm production should, too, after a couple of cycles of spermatogenesis.
Research suggests that it typically takes about 2 to 4 months for sperm to return to pre-fever levels.
Interestingly, case reports show varying recovery times. One report looked at men who had a fever and found that it took anywhere from 20 to 79 days for sperm production to return to normal.
Should I Do a Semen Analysis if I Recently Had a Fever?
If you’ve recently had a fever and you’re curious about your sperm health, and are considering ways to boost fertility, including supplements like CoQ10, it’s important to time your semen analysis carefully. To get the most accurate results, it’s best to wait at least two months after your fever has subsided before providing a sample.
Also, keep in mind that doctors usually recommend abstaining from ejaculation for 2–5 days before producing a sample for a semen analysis, which can sometimes lead to questions about normal sperm release. Following these guidelines will help ensure that your results are as reliable as possible.
Factors That Minimize the Risk
Okay, so a fever can affect sperm, but here’s the good news: short-term or mild fevers are less likely to cause lasting damage. One study even showed that a scrotal temperature increase of less than 2°F didn’t seem to impact sperm production.
However, research also indicates that the longer the fever lasts, the greater the potential impact on sperm quality. That’s why it’s essential to address the root cause of the fever quickly. Treating the underlying illness promptly can minimize the fever’s duration and, in turn, lessen any potential effects on sperm health. So, rest up, take your meds (if prescribed), and let your body heal!
Addressing Common Concerns
Can Getting Sick Affect My Fertility?
Yes, unfortunately, a fever can temporarily affect sperm quality. If you have a febrile illness — meaning you’re sick and have a fever — that lasts for several days with a temperature of 101°F or higher, it can significantly affect sperm count and quality. However, these effects are generally reversible.
Can Getting a Vaccine Affect My Fertility?
Probably not. Vaccines like the COVID-19 vaccine are not likely to impact sperm health. Multiple small studies of the COVID-19 vaccine showed no impact on sperm count or motility (movement).
Frequently Asked Questions
Is a fever a high-risk pregnancy?
A fever during pregnancy can potentially pose risks, especially during the first trimester. High fevers have been linked to certain birth defects. It’s important to contact your healthcare provider if you develop a fever while pregnant so they can help you manage it safely.
Can a fever kill a pregnancy?
While a fever can potentially impact a pregnancy, it’s not typically a direct cause of pregnancy loss. Very high and prolonged fevers, particularly early in pregnancy, may increase the risk of miscarriage or birth defects, but this is not a common occurrence. Management of fever and underlying illness is key.
Is 99.5 a fever?
A temperature of 99.5°F (37.5°C) is slightly elevated but not typically considered a high fever. Generally, a fever is defined as a temperature of 100.4°F (38°C) or higher. However, if you’re concerned about a temperature of 99.5°F, especially if you have other symptoms, it’s always best to consult with your doctor.
Is it bad to try to conceive while sick?
Trying to conceive while sick isn’t necessarily “bad,” but it’s important to consider a few factors. If you have a fever or illness, your body is already under stress. It might be wise to focus on recovering and feeling better before trying to conceive. Additionally, some medications you might take while sick could potentially affect fertility or early pregnancy. Discuss any concerns with your healthcare provider.
Does Tylenol affect sperm?
Some studies have suggested that prolonged use of acetaminophen (Tylenol) may potentially affect male fertility by impacting hormone production. Other research has not found any adverse effect. If you have concerns about Tylenol’s effects on sperm, it’s best to consult with a healthcare professional.
Summary
A fever can temporarily impact sperm quality. It can affect sperm count, how well sperm swim (motility), the shape of sperm (morphology), and even DNA fragmentation.
If you’ve had a fever, it’s crucial to wait before having a semen analysis. Waiting at least two months after your fever breaks is generally recommended to allow sperm production to return to normal.
If you’re concerned about your fertility after a fever, or are experiencing any discomfort such as testicle pain, the best step is to talk with a healthcare professional or a fertility specialist. They can provide personalized advice based on your individual circumstances and help you navigate any potential challenges.