According to a National Institute of Child Health and Human Development (NICHD) study, infertility is a multifactorial illness that impacts 15% of couples of reproductive age. Both male and female factors contribute to infertility. Infertility is the inability to commence or sustain a pregnancy with a year of sexual activity without contraception. However, there are numerous explanations for infertility, and different classifications can be established depending on how these explanations are approached.
Like other multifactorial disorders, its development is influenced by environmental factors as well as hereditary or epigenetic abnormalities. This makes it highly challenging to pinpoint its root cause. Occasionally, it can also be brought on by an inherited chromosome issue. Sometimes, it results from a defect in a single gene that parents pass on to their offspring. In this blog post, we'll examine whether the medical problem of infertility is hereditary and how genetic testing solutions may contribute to it.
Infertility often arises in couples due to underlying genetic issues, which may have been inherited. As infertility is complex, it's important to note that most cases don't have a known genetic cause. Up to 30% of infertility cases may have a hereditary reason, affecting both men and women equally.
Chromosome abnormalities, whether they involve the number or structure of chromosomes, represent a primary genetic factor contributing to infertility in couples struggling to conceive. Furthermore, genetic alterations can manifest at the DNA level, involving specific gene mutations and chromosomal irregularities. It's essential to consider specific genetic tests in each case to pinpoint the underlying cause accurately.
Exploring the Genetic Factors Behind Male and Female Infertility
Genetic disorders typically fall into two primary categories: chromosomal abnormalities and single-gene defects. A single gene defect is an abnormality or mutation in the DNA responsible for a specific gene. Such single gene abnormalities can lead to conditions that may affect fertility. On the other hand, chromosomal abnormalities involve alterations in the structure or number of chromosomes that house the DNA. Both males and females can experience various outcomes from inherited chromosomal abnormalities and gene mutations. These outcomes include:
- Deletion in which a chromosome's structure goes missing.
- Inversion in which the chromosome goes upside down.
- Mutation, in which the DNA sequence of a gene is altered.
- Aneuploidy in which there are either too many or too few chromosomal numbers.
- Translocation, in which chromosomal fragments are linked to the wrong chromosome.
Reasons for female infertility
The likelihood of facing difficulties in conceiving is higher for women who have a family history of endometriosis or early menopause. In women, chromosome abnormalities can be associated with pregnancy loss or infant clinical issues, such as Down syndrome. Furthermore, certain gene mutations or chromosomal abnormalities can affect a woman's ability to ovulate, thereby contributing to female infertility. Here are some examples of these conditions:
- Underdeveloped ovaries are a symptom of Turner syndrome caused by either a missing or altered X chromosome in females.
- Permutation of the fragile X chromosome affects the FMR1 gene, which is present on the X chromosome and results in lower ovarian productivity and reproductive issues.
- Women with thicker cervical mucus, inadequate nutrition, or problems with ovulation may be affected by cystic fibrosis gene mutations.
- Kallmann syndrome may lead to infertility issues due to the inability to create hypothalamus or pituitary hormones.
- Women who have primary ciliary dyskinesia, a chronic respiratory infection, will be unable to conceive because of defective cilia in their fallopian tubes.
Reasons for male infertility
Male infertility often results from gene alterations or chromosomal abnormalities that affect sperm production or the flow of sperm. Chromosomal abnormalities can be connected to low sperm counts in men. Conditions like azoospermia, characterised by the absence of sperm, may be associated with gene mutations related to cystic fibrosis or deletions in Y-chromosome genes. It is advisable for all males with low sperm counts to undergo genetic testing. Here are some examples of these conditions:
- Mutations in the cystic fibrosis gene can lead to the lack of sperm transport ducts, resulting in infertility.
- Men with an additional X chromosome may develop Klinefelter syndrome, which affects the synthesis of sperm and testosterone.
- The absence of a segment on the Y chromosome can lead to a man having difficulty achieving a regular sperm count.
Infertility is seldom solely the result of genetic factors, as multiple causes typically contribute to the condition. Fortunately, advancements in infertility treatment have significantly improved over time and continue to advance. Even genetic factors can frequently be effectively addressed with the right treatment protocols.
Genetic Conditions Impacting Fertility & Genetic Testing Solutions- An Overview
A physician can do a number of tests if you're having trouble conceiving to determine the source of your reproductive issues. These may consist of:
- A detailed analysis of the sexual and medical histories of both the partners
- A physical assessment
- A semen analysis that examines sperm quantity, quality, and motility
- Blood tests to assess the signs of ovulation or hormone levels
- Imaging examinations to look for reproductive system structural disorders
Your doctor might advise genetic testing if they think your fertility problems may be hereditary. Preconception carrier screening (PCS) is performed using a blood sample and checks one for a variety of genetic conditions that could cause infertility or be passed on to your offspring. In order to ensure that you have 23 sets of chromosomes, doctors will also use the blood sample to examine your karyotype.
Treatment for genetic conditions
You might be exploring treatment options if you've been diagnosed with a genetic disorder impacting fertility. Structural changes in the reproductive system that hinder fertility can often be addressed through surgery. In cases of low hormone levels, restoring or supplementing hormones may lead to successful conception for some couples.
Natural conception may still be challenging for some people. As a result, other strategies might be suggested. These include assisted reproductive technology and intrauterine insemination (IUI), which includes procedures like intracytoplasmic sperm injection (ICSI) and in vitro fertilisation (IVF).
Doctors recommend patients undergo blood testing before starting IVF or any other reproductive treatment. Preimplantation genetic testing (PGT) is a diagnostic technique that assesses foetuses for single-gene or chromosomal abnormalities before being implanted into the uterus as part of an IVF cycle. Preimplantation genetic diagnosis (PGD/PGS/PGT-A) can prevent the transmission of genetic abnormalities when used along with IVF. Here are some of the applications for PGD/PGS/PGT-A testing:
- Check for any hereditary health conditions you may be unaware of.
- Examine the existing hereditary disorders that could potentially hinder your fertility.
- Minimise the likelihood of passing genetic illnesses to your future children.
- Select the desired gender of the embryo to be transferred during IVF.
If you've been attempting to conceive without success for an extended period, you must consider seeking the help of a specialist. Contact Anderson Diagnostics to get the best genetic testing solutions in Chennai and eliminate any potential medical factors contributing to your infertility with the right treatment options.