Can a father’s medication affect fertility and pregnancy?
September 28, 2021
There is a lot of research devoted to evaluating how medications a woman takes affect pregnancy. But what about those taken by men?
Much less research has been done in this area, but providers are becoming increasingly aware of the potential impact a father’s medications could have on pregnancy – before and after conception.
I recently researched the paternal safety of anti-rheumatic medications, and while more data must be gathered, findings to date show that most of those drugs do not affect men’s fertility or pose a risk to a partner’s pregnancy.
However, that doesn’t mean all medications are safe. If you plan to father a child, talk with your health care provider about how your medications might affect fertility and pregnancy, as well as options to reduce any potential risks.
Drugs that could reduce male fertility
Very few drugs are known to affect male fertility permanently. The most common are cytotoxic drugs, which are used in chemotherapy and to treat certain rheumatoid disorders, such as lupus, vasculitis, and severe rheumatoid arthritis.
Before you start taking cytotoxic medication, discuss with your doctor fertility preservation options such as sperm banking.
There are some medications that can cause low sperm counts or reduce sperm motility. Some of the more common of these include:
- 5-alpha-reductase inhibitors such as Propecia and Avodart to treat prostate enlargement and hair loss
- Alpha blockers used to treat urinary symptoms caused by an enlarged prostate
- Antidepressants, specifically selective serotonin reuptake inhibitors (SSRIs)
- Anti-epilepsy drugs
Fertility problems associated with these drugs often go away after you stop taking them, although it can take several months to a year for sperm production to return to normal.
If you’re having trouble conceiving while taking a medication with a known negative effect on fertility, talk with your doctor about whether it’s safe to stop taking it for several months. Then get a sperm analysis to determine whether the issue is the drug or a pre-existing fertility factor.
How a father’s medication may impact a developing baby
Even if your medication does not affect your fertility, you may still be concerned it could harm your baby – before or after conception. The good news is that outcome is quite rare.
While medications you take might be found in semen, the amount is generally very low. Furthermore, absorption in the vagina during sex is also very low, so potential exposure is unlikely to harm your developing baby.
A 2013 study of 340,000 pregnancies found no increase in adverse pregnancy outcomes among fathers who were prescribed a medication known to be harmful to babies when taken by a pregnant woman. In the late 1950s and early 1960s, thalidomide was prescribed to pregnant women to relieve nausea. Tragically, it resulted in severe birth defects in thousands of children.
Today, thalidomide is used to treat Hansen’s disease (formerly known as leprosy) and some rheumatic disorders, AIDS-related conditions, and cancers. While the levels of thalidomide found in semen have been very low, the risk level for the fetus is enough that we err on the side of caution and recommend men avoid the drug for three months before conception.
Some cytotoxic drugs also can damage DNA in sperm cells, which can result in pregnancy loss, preterm birth, or an increased risk of birth defects. Again, in these cases your doctor may recommend you avoid the drug for three months before trying to conceive.
Why three months? Because sperm formation takes about 74 days and another 12 to 21 days to make it to the ejaculatory ducts.
Worried about your medication? Don’t hesitate to ask
If you and your partner are thinking about becoming parents or your partner is already pregnant, let your health care provider know so you can discuss potential fertility obstacles related to your condition or medication and how to mitigate them – whether that means putting a medication on hold, changing to a new one, or undergoing fertility preservation procedures.
As with anything related to your health, you should always feel comfortable to ask questions about any prescribed or over-the-counter medication. We want to do everything we can to keep you healthy while also helping you achieve your family goals.