Fertility challenges affect millions of couples worldwide. In some cases, the cause of infertility is still unexplained. Hormone levels, ovulation timing, and sperm quality are often evaluated. But genetic problems are often overlooked in this process. Genetic testing for fertility finds chromosomal problems, inherited disorders, and DNA issues.
These factors can affect both male and female fertility. Knowing how DNA tests work can help couples make better choices about their reproductive health and treatment.
How do genetic factors affect fertility?
When you think about fertility, timing is important. Physical health matters too. Genetic factors can also influence natural conception and IVF treatments. Our DNA acts as a blueprint; if there is a mistake in that code, it can lead to infertility symptoms or pregnancy loss.
Specific genetic disorders or chromosomal abnormalities can interfere with how an embryo develops.
In female infertility, these issues can lower egg quality or decrease the number of eggs. For men, genetic factors can cause low sperm count or poor motility. A healthy pregnancy needs balanced DNA from both partners. So, even small genetic changes can affect your chances of having a baby.
What is genetic testing for fertility?
You might want to know: What is genetic testing, and what is a DNA test? DNA stands for deoxyribonucleic acid. In the fertility space, it is a way to look at your biological code to find hidden obstacles.
Genetic analysis involves taking a sample of blood or saliva to look for:
- Gene mutations: Small changes in specific genes.
- Chromosomal changes: Issues with the structure or number of chromosomes.
- Carrier status: Whether you carry a “hidden” disease gene that could be passed on to a child.
Genetic testing during pregnancy or before conception is different from a regular checkup. It looks at the core of your reproductive health.
Types of genetic tests used in fertility treatment
Doctors use different types of DNA analysis depending on your history. Here are the most common tools:
Carrier screening
This is often done before pregnancy. It checks if you or your partner have genes for cystic fibrosis. It also checks for sickle cell disease. If both parents are carriers, there is a 25% chance the baby will inherit the disorder.
Karyotype testing
This test looks at the size, shape, and number of your chromosomes. It can be helpful for couples who have had multiple miscarriages. It does this by finding “swapped” DNA pieces called translocations.
Sperm DNA fragmentation test
A sperm fragmentation test looks deeper than a standard semen analysis. It checks for damage within the sperm’s genetic material. Even if a man has a “normal” sperm count, high fragmentation can lead to male infertility.
Preimplantation genetic testing (PGT)
If you are undergoing In Vitro Fertilisation (IVF), you might hear the term ‘PGT.’ This stands for Preimplantation Genetic Testing, where embryos are screened before they are transferred to the uterus.
PGT-A vs. PGT-M: What is the difference?
Understanding the difference between these two is key for patients:
- PGT-A (Aneuploidy): Screens for the correct number of chromosomes (46). Most miscarriages are caused by an incorrect number of chromosomes. This test is often recommended as women age.
- PGT-M (Monogenic): Specifically looks for a single-gene disorder that the parents are known carriers of (like the ones found in carrier screening).
| Test Type | What It Detects | Mostly Recommended For |
| Carrier Screening | Specific inherited diseases (Cystic Fibrosis, etc.) | Anyone who is planning a pregnancy |
| Karyotyping | Large-scale chromosomal changes | Couples with recurrent loss |
| PGT-A | An abnormal number of chromosomes in embryos | Women over 35 or IVF patients |
| Fragile X | Gene changes linked to ovarian health | Women with irregular cycles/early menopause |
What is sperm DNA fragmentation, and why does it matter?
Sperm DNA fragmentation refers to breaks or damage in the strands of DNA within the sperm. This is a common but often “invisible” cause of infertility.
A sperm DNA fragmentation test measures the DNA Fragmentation Index (DFI). Generally:
- Under 15% DFI: Optimal fertility
- 15–25% DFI: Moderate risk or delayed “time to pregnancy”
- Over 25% DFI: Significantly higher risk of male infertility and miscarriage
Causes of damage include smoking, high heat, older age, or “oxidative stress.” You can boost male fertility and lower these scores through lifestyle changes and an antioxidant-rich diet.
Genetic causes of male infertility
Male fertility is just as important as female fertility. Sometimes, the cause of a low sperm count is written in the genes. Common genetic problems include:
- Y Chromosome microdeletions: Missing pieces of DNA on the male chromosome that stop sperm production
- Klinefelter syndrome: Having an extra X chromosome (XXY)
- Cystic fibrosis mutation: Causes a physical blockage preventing sperm from being released
Genetic causes of female infertility
There are several female infertility causes rooted in DNA. Genetic issues can affect how long a woman remains fertile or how her body responds to pregnancy.
- Fragile X premutation: Linked to early menopause or “premature ovarian insufficiency”
- Balanced translocations: Occur when a woman is healthy, but her eggs often have missing or extra DNA, which can lead to miscarriages
- Age-related damage: Happens as women age, as the DNA in their eggs naturally becomes more prone to errors (aneuploidy)
When should you consider genetic testing?
You don’t always need a DNA test right away, but it is highly recommended if you have experienced any of the following conditions:
- Two or more miscarriages in a row
- Multiple failed IVF cycles
- A diagnosis of “unexplained infertility”
- Very low sperm counts or poor embryo quality
- A known family history of genetic disorders
Can genetic testing improve IVF success?
While testing doesn’t “cure” genetic factors, it can act as a powerful roadmap. By using PGT-A (testing embryos for the right number of chromosomes), specialists can select the healthiest embryo.
This reduces the time it takes to get pregnant and lowers the risk of pregnancy loss. Identifying sperm DNA fragmentation helps doctors pick the best sperm for fertilisation. They use special techniques for this.
Limitations of genetic testing
It is important to have realistic expectations. Genetic testing is a great tool, but:
- It cannot guarantee a 100% healthy pregnancy
- It can be expensive depending on your insurance
- It may reveal information that is emotionally difficult to process
Ready to take the next step?
While a lab handles your DNA test, you can track your body’s daily signals with the Premom app. By monitoring your ovulation and cycles, you can get a full view of your reproductive health.
Take the next step with confidence
If you are planning a pregnancy, do not miss our guide on Essential Pre-Pregnancy Tests You Should Not Miss to understand the basic tests every couple should consider before trying to conceive.
If you have questions about genetic testing, miscarriages, IVF, or unexplained infertility, you can connect with a fertility expert through the Ask an Expert (AAE) section inside the Premom app for clear, personalised guidance.
Frequently asked questions (FAQs) – DNA Genetic Testing
Deciding to get genetic testing is a personal choice. Knowing how DNA tests work helps couples make better choices about their reproductive health and treatment. While it may not be required, many doctors still recommend carrier screening as a proactive step. Some couples get tested for peace of mind to see if they carry any recessive traits. Others skip the test if they don’t have a family history of genetic conditions.
PGT-A can’t stop every miscarriage, but it can lower the risk. It does this by ensuring that only embryos with the right number of chromosomes are used.
The cost of genetic testing for starting a family depends on your insurance and the tests you choose. Most basic carrier screens are now covered by insurance or offered at a low flat rate from specialised labs.
It acts as a roadmap to uncover ‘hidden’ obstacles. Identifying genetic issues early helps you avoid the stress of failed treatments. It also lets you choose better options, like IVF with embryo screening.
Fertility genetic tests primarily look for:
* Carrier status: Inherited ‘recessive’ genes you might pass on to your child
* Chromosomal structure: Changes like “translocations,” where pieces of DNA are swapped
* Aneuploidy: Ensuring an embryo has the correct number of chromosomes (46)
* Specific mutations: Changes like Fragile X that impact ovarian health and egg count
* Carrier screening: Best for proactive planning before pregnancy
* Karyotyping: Essential for those with a history of recurrent pregnancy loss
* PGT (Preimplantation genetic testing): Done on embryos during IVF, helps to choose the healthiest ones for transfer
These are ‘single-gene’ disorders caused entirely by a mutation in one specific gene. Common examples are cystic fibrosis, sickle cell anemia, Tay-Sachs disease, and Huntington’s disease.
Also called an ‘expanded carrier screen,’ this test checks for hundreds of genetic conditions (often 250+) at once. It offers a complete view of rare inherited disorders. This applies to everyone, no matter their family history or ethnicity.
References
- American College of Obstetricians and Gynecologists. Carrier screening for genetic conditions. ACOG Committee Opinion No. 691. 2017;129(3):e41-e55. https://pubmed.ncbi.nlm.nih.gov/28225426/
- Practice Committee of the American Society for Reproductive Medicine. The role of genetic testing in the evaluation of infertility. Fertil Steril. 2017;107(6):1296-1305. https://pmc.ncbi.nlm.nih.gov/articles/PMC6694655/
- Franasiak JM, et al. The nature of aneuploidy with increasing age of the female partner. Fertil Steril. 2014;101(3):656-663. https://pubmed.ncbi.nlm.nih.gov/24355045/
- Munné S, et al. Preimplantation genetic testing for aneuploidy (PGT-A). Nature Reviews Disease Primers. 2021;7(1):1-15.https://pmc.ncbi.nlm.nih.gov/articles/PMC8995221/
