Many women are unaware that they have Fragile X premutation until they are trying to conceive, and experience difficulties. Fragile X is associated with three known disorders, including Fragile X Syndrome. For women who are carriers of Fragile X, one of the most common symptoms is infertility.
What Is Fragile X?
Women with a Fragile X premutation can be carriers for three genetic disorders, including Fragile X Syndrome. This genetic disorder is related to a mutation in the gene FMR1. The percentage of Fragile X women carriers in the US was 1.3%.
Fragile X Syndrome can cause mental retardation in males, which can affect 1/4000 (or roughly .00025%) of the population.
How Does It Affect Fertility?
Women carriers for Fragile X have been known to develop Fragile X Primary Ovarian Insufficiency, known as FXPOI, which can cause a decreased ovarian reserve, and eventually cause Premature Ovarian Failure. In FXPOI, the ovaries do not function at capacity. Fragile X carriers may find that, when trying to conceive, that they experience infertility, high FSH, low antral follicle count, and other symptoms congruent with a low ovarian reserve.
Additionally, symptoms of FXPOI may mimic menopause including missing or irregular periods such as long cycles over 35 days, or short cycles less than 21 days, vaginal dryness, and hot flashes. However, it is not the same as menopause, as women with FXPOI may get pregnant, and experience a return in their cycles, while women who enter menopause cannot.
On average, women of childbearing age who are experiencing a low ovarian reserve or ovarian insufficiency, only 4-6% have been found to be Fragile X carriers. And of women who are found to be carriers for a FMR1 premutation, only 20-25% experience FXPOI.
How Is Fragile X Tested?
Women can be tested to see if they are carriers for Fragile X premutation. The standard test for detecting Fragile X is the “FMR1 DNA Test” and is capable of diagnosing over 99% of women who are Fragile X carriers. Blood tests range from $300-$600, and the results are most often available within 2-4 weeks.
Pregnancy With FMR1 Premutation
Women with FMR1 Fragile X premutation can get pregnant. All carriers, however, are encouraged to meet with your doctor and/or genetic counselors to discuss issues, and risk of having children with Fragile X Syndrome.
Women who conceive naturally can opt for prenatal testing, done through amniocentesis or CVS, Chorionic Villus Sampling, to determine genetic status of the fetus.
In addition, there are reproductive options, including PCD, Pre-Implantation Genetic Diagnosis, which involves a woman having her eggs removed through in vitro (IVF) and analyzed in the lab to eliminate any affected eggs, so only unaffected eggs are implanted. There are also additional options including using donor eggs.
Talk To Your Doctor
If you are concerned, make an appointment and discuss your thoughts with your doctor. Your doctor can direct you to the proper testing and make the correct diagnosis that will help you and your fertility.