What Is a Balanced Translocation and How Does It Affect Pregnancy?

When you’ve experienced multiple pregnancy losses, it’s natural to start asking deeper questions. Why is this happening to me? Could there be something more going on? That’s exactly where Alice found herself after five miscarriages over six years. It was only after her fifth loss that she finally got an answer: she is a balanced translocation carrier.

 

• What Is a Balanced Translocation?

 

A balanced translocation is a type of chromosomal rearrangement. Humans typically have 23 pairs of chromosomes, which carry our DNA and genetic instructions. In a balanced translocation, two chromosomes swap pieces with each other. The key word is “balanced”—because even though the parts have swapped, there is no missing or extra genetic material.

For the person carrying the translocation, this usually causes no health problems. Most people never even know they have it. They live their whole lives without symptoms.

But where it becomes relevant and heartbreaking is when it comes to reproduction.

 

• How Does a Balanced Translocation Affect Pregnancy?

 

When a balanced translocation carrier produces eggs or sperm, the chromosomes may not line up or divide correctly. This can result in unbalanced embryos which means embryos that have missing or extra genetic material.

Unbalanced embryos often:

• Fail to implant,

• Result in early miscarriage,

• Or may lead to serious conditions if the pregnancy continues.

 

This means someone like Alice, whose body is completely healthy, may still experience multiple losses simply because of how her genetic material is arranged.

 

• How Do You Know If You’re a Balanced Translocation Carrier?

 

There’s a simple blood test called a karyotype test that checks the number and structure of your chromosomes. Both partners can be tested.

It’s usually not offered until after three miscarriages but Alice (and many others) wish they had done it sooner.

If you’ve experienced:

• Two or more miscarriages,

• Stillbirths, or

• IVF failure with good-quality embryos,

 

You might want to ask your doctor or fertility specialist about getting a karyotype test. It’s available on the NHS in the UK (though sometimes delayed or inconsistent), and privately at fertility clinics.

Alice and her partner chose to pay for the test privately after years of heartache. The results showed that chromosome 16 and chromosome 20 had swapped arms which is something that doesn’t affect her day-to-day health but was likely behind her repeated miscarriages.

 

• What Are the Options After a Balanced Translocation Diagnosis?

 

Finding out you’re a carrier doesn’t mean you can’t become a parent but it might shift your path.

Some of the options people explore include:

• IVF with genetic testing of embryos (PGT-A or PGT-SR): to select embryos that aren’t unbalanced.

• Using an egg or sperm donor: if the carrier’s eggs or sperm are repeatedly resulting in unbalanced embryos.

• Natural conception with close monitoring: knowing that some carriers do go on to have healthy pregnancies.

• Adoption or living child-free: for those who decide not to pursue more medical intervention.

 

None of these choices are easy, but having information gives you power and a clearer understanding of your options.

 

• Final Thoughts from Alice

 

If you’ve been through multiple losses, don’t be afraid to advocate for yourself.

Ask about a karyotype test. Share your story. You deserve answers. You deserve care.

 

Follow Alice on Instagram: https://www.instagram.com/headfullofjoy