What drugs can affect fertility?

What is infertility? 

Fertility is the ability of a person to have children, while infertility is defined as a disease of the male or female reproductive system that results in the inability to achieve pregnancy after 12 months or more of regular unprotected sexual intercourse.

Millions of people around the world are affected by infertility, which has a significant impact on their families and their lives. It is estimated that around 1 in 6 people of childbearing age worldwide have experienced infertility at some point in their lives.

In the male reproductive system, the inability to conceive is generally linked to such disorders as impaired ejaculation, the absence or insufficient quantity of spermatozoa, and abnormalities in sperm morphology and movement.

In the female reproductive system, the inability to conceive can result from a variety of conditions affecting the ovaries, uterus, fallopian tubes and the endocrine system, among others.

Apart from the above-mentioned health conditions, certain drug treatments can also affect a person's ability to conceive a child.

What drugs can affect fertility? 

Chemotherapy

Many chemotherapy drugs can disrupt a woman's menstrual cycle, leading to irregular or even absent menstrual cycles, as well as changes in the amount of bleeding. They can also have an impact on men's reproductive system: for example, sperm counts may be reduced. 

Some cancer treatments can even render patients sterile. In this case, if patients want to have children, they should contact a special establishment for the study and conservation of eggs and human sperm prior to treatment.

Opioids like morphine, fentanyl, etc

Drugs from the opioid family could potentially reduce fertility. These drugs are used to treat very intense pain, and are known as "level III analgesics". Since there are only 3 levels, this is the highest. 

Preclinical toxicology studies on animals, particularly rats, have shown a tendency towards reduced fertility. Female rats showed an increase in the death of embryos in the womb, and male rats showed reduced fertility and abnormal spermatozoa. 

In humans, a study on the effects of morphine abuse showed a reduction in sperm mobility and quality and an increase in the rate of sperm death (apoptosis). 

Non-steroidal anti-inflammatory drugs (ibuprofen, diclofenac, naproxen, etc)  

Non-steroidal anti-inflammatory drugs (NSAIDs) can also affect fertility. In women, they have an inhibitory effect on ovulation, which may, however, be reversed as soon as the treatment is stopped. As a result, these medications are not recommended for women who would like to have children. 

Antidepressants 

Antidepressants from the selective serotonin reuptake inhibitor (SSRI) family, such as fluoxetine or paroxetine, are likely to reduce fertility. These drugs are prescribed for adults suffering from depression and/or anxiety. For example, they are used to treat panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder (PTSD) or generalised anxiety disorder (GAD). 

Several studies of various SSRIs have shown that they are linked to the following effects: reduced sperm concentration and mobility, and reduced reproductive organ weight. However, a recent study suggests that these effects are reversible once the treatment is stopped.

Sulfasalazine

Sulfasalazine is prescribed for the treatment of ulcerative colitis (UC) and Crohn's disease, as well as rheumatoid arthritis. It affects male fertility by reducing the number and mobility of spermatozoa.

Methotrexate 

Methotrexate has the same indications as sulphasalazine, but can also be used to treat certain types of blood cancer.

It not only reduces fertility, but is also responsible for higher risks of congenital malformations. Thus, contraception must be used in both men and women, throughout the course of treatment. Women must use contraception up to 6 months after stopping their treatment by methotrexate.

This is a non-exhaustive list of drugs that can reduce fertility. If you are taking a treatment and wondering about its effect on your fertility, you should refer to the package leaflet or ask your doctor or pharmacist for advice.