Some fertility issues are genetic. Genetic diseases usually run in families, but some can occur for the first time in an individual and from then can be passed down to their future children. Here are some examples of common and rare genetic causes of infertility.
While not the only risk factor, endometriosis is 7 times more common in women with a family history of endometriosis with their mother or sister affected. This implies that our genes carry some blame but it’s complicated. No specific one gene is to blame and environmental factors also play an important part.
PCOS is a multifactorial condition but often does run in families. PCOS can also be associated with a family history of relatives developing gestational diabetes in pregnancy and Type 2 diabetes later in life.
Structural disorders of the chromosomes like translocations and inversions can develop in us or can be inherited from a parent. Carrying a translocation is a cause of both infertility and recurrent miscarriages and can also sometimes increase your risk of having a baby affected by a severe genetic syndrome. This condition can be diagnosed by a genetic blood test called a karyotype and is equally important when carried by the male so both partners need to be tested to rule it out. A translocation in sperm can cause all the same problems as a translocation in eggs – half a baby’s DNA comes from each parent. This kind of problem can have delayed detection if investigating the male partner of an infertile couple is delayed. It is so important to look deeply into both men and women suffering infertility – even when the semen analysis looks normal on paper as it usually does in this circumstance.
Male fertility problems needing IVF
Studies have proved that unfortunately, male factor infertility can be passed down genetically. Sons conceived with the help of fertility treatments like IVF and sperm micro-injection (ICSI) are more likely to require the same kind of help to conceive themselves.
Inherited genetic diseases
Problems and mutations in individual genes can cause hereditary infertility. An example is the FRAX1 gene which expands slowly when passed down through families and eventually goes from normal length, to pre-mutation length and eventually causes the disease fragile X syndrome. In women, carrying a Fragile-X pre-mutation causes low ovarian reserve, premature ovarian insufficiency and early menopause.
There are literally thousands of individual genes and proteins involved in fertility in both men and women. We are learning more and more about them. It is likely that a lot of what we now label unexplained infertility is in fact due to a specific genetic issue that we just haven’t discovered yet. Happily, because IVF helps us to skip over a lot of steps in the incredible baby making process that occur in nature, we can solve the problem of unexplained infertility for many couples by getting around it despite not yet understanding it completely.