Over the last 20 years, our understanding of the human genome has grown dramatically. With that knowledge, we can now identify conditions that stem from tiny alterations in a person’s genes. Genetic disorders can have a huge impact on every aspect of our health, including fertility. Since it’s hard to treat an illness that is written into your DNA, it can be difficult to overcome these conditions. Let’s take a look at how genes can affect fertility in both women and men.
Genetic Causes of Female Infertility
Various genetic conditions can result in limited fertility or complete infertility in women. They can affect a woman’s body in numerous ways, from broad structural problems to improper hormonal development. Just a couple examples of these conditions include the following:
- Kallman syndrome is a condition that can result in incomplete puberty or even lack of puberty. Women with Kallman syndrome may not experience menstrual periods.
- In patients with Turner syndrome, one of a woman’s X chromosomes is either missing or misshapen. In addition to more visible physical signs like a webbed neck and swelling in the hands and feet, women with this condition may experience premature ovarian failure, limiting fertility options.
- Müllerian agenesis (aka Mayer-Romansky-Kuster-Hauser Syndrome) results in the uterus not forming during fetal development. Ovaries still develop, but without a working uterus, the woman is infertile.
Fortunately, for many women with genetic disorders, treatment or solutions for infertility are often possible by addressing or working around the symptoms of the condition. For example:
- Hormone therapy can be effective in cases of Kallman syndrome.
- Reproductive technologies and donor eggs may allow a woman with Turner syndrome to become a mother.
- A woman with Müllerian agenesis can still harvest her eggs and have them carried by a surrogate.
Genetic Causes of Male Infertility
Genetic disorders in men affect the production of sperm and sexual development in general. For example:
- Kallman syndrome also affects men and results in low levels of testosterone, LH, and FSH, the hormones responsible for fertility. Almost all men with Kallman syndrome also experience decreased libido and erectile dysfunction.
- Y chromosome microdeletion is a genetic disorder that can result in low sperm count, no sperm production, or abnormal sperm morphology and motility. Some men with this disorder may have small or undescended testes.
- Men with Klinefelter syndrome have smaller testes than average and produce less testosterone than normal. This leads to delayed or incomplete puberty, infertility, and other physical symptoms.
Treatment is also available for male genetic disorders. Often, these involve collection of what sperm is available, as well as hormone replacement treatments. For example:
- Hormone replacement can treat the decreased libido and erectile dysfunction of Kallman syndrome, as well as potentially stimulate fertility.
- In about two-thirds of cases of Y chromosome microdeletion, some sperm can be extracted from the testes and used in assisted reproduction. Sperm production in these cases may also respond to the natural lifestyle changes often suggested for men without the condition.
- While testosterone treatments can help with many of the physical effects of Klinefelter syndrome, it typically won’t improve fertility. Some men with the condition may have minimal sperm production, in which case sperm may be extracted for use in other procedures. Read: Male Hormones and Fertility (What You Need to Know)
Every individual is different, and so managing the range of genetic causes of infertility is often not a “one size fits all” solution. If you have questions about genetic disorders and their possible role in your fertility, consult with your doctor. They may suggest tests or screenings that can determine if you have a disorder.