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Recurrent miscarriage

Too many people experience the heartbreak of miscarriage. It isn’t really possible to know exactly how many miscarriages occur because sometimes a miscarriage can happen before pregnancy is confirmed, but studies indicate that miscarriage occurs in around 1 in 4 recognised pregnancies, with 85% of those happening in the first trimester (weeks 1 to 12).

What is Recurrent Miscarriage?

Recurrent miscarriage is usually defined as having three or more miscarriages in a row, i.e. the loss of three or more pregnancies before 24 weeks with no successful pregnancies in between. Going through a miscarriage or unsuccessful IVF treatment is extremely difficult and we will do everything we can to help you

What are the causes of recurrent miscarriage?

Sadly, there can be a number of reasons why an embryo doesn’t attach in the uterus or miscarries in early pregnancy.

There are a number of tests and treatment available at Care that can help identify the causes and allow us to create a tailored treatment plan designed to help you have a healthy baby.

Medical science has yet to help us fully understand all the possible reasons but in general terms miscarriage or implantation failure can happen for a number of reasons including:

  • The embryo is not viable
  • Endometrial health
  • Immune issues
  • Presence of the C4M2 variant in the Annexin A5 Gene
  • The uterus

We know from scientific evidence that genetic abnormalities in embryos increase with the age of the egg provider. We may suggest using PGT-A to test the genetic makeup of your embryos to check that they have the correct number of chromosomes.

It is also possible for a perfectly healthy person to have structural mutations in their chromosomes that don’t cause any problems for them, but cause serious genetic imbalances in embryos created with their eggs or sperm. Genetic abnormalities can lead to failed implantation and miscarriage.

Genetic abnormalities such as the C4M2 variant linked to blood clotting disorders which can lead to failed implantation and miscarriage. Our recurrent miscarriage test, CareUnity, can identify this abnormality and help us to plan future treatments accordingly.

The endometrium is a tissue lining the interior of the uterus, it’s where embryos implant and complex physiological processes take place. The endometrium must be both receptive to embryo implantation at the time of transfer and rich in healthy bacteria. We can test for infections which can cause endometrial issues and are associated with poor reproductive outcomes. Also, since implantation timing is critical, endometrial testing can help us determine the most appropriate time for embryo transfer.

An abnormally-shaped womb can also increase your risk of recurrent miscarriage. This is usually diagnosed with an ultrasound that can be used to check the structure of your womb for any abnormalities.

Natural killer cells (NK cells) form part of the body’s immune system. They help the body fight infection and every organ has these cells, including the womb.

NK cells in the uterus are known as uNK cells. They play an important role in helping the body become pregnant.

In order to become pregnant, the womb lining needs to inflame slightly so the embryo can attach (or implant) to the uterine wall. uNK cells contribute to this process of inflammation, and when there are too many or not enough uNK cells, this can cause too much or not enough inflammation, which are both associated with infertility and miscarriage.

It is possible to have tests to measure your level of NK cells. If you do decide to go ahead with tests or treatment, please be aware that whilst some studies show benefits of this testing, they are rated Red by the HFEA, as they do not believe there is enough evidence to show that they are effective at improving the chances of having a baby for most fertility patients.

What do the recurrent miscarriage and implantation failure investigations involve?

We do two levels of tests to investigate possible causes of implantation failure or recurrent miscarriage, these include tests for chromosomal abnormalities (PGT-A), CareUnity and DNA damage or oxidative stress in the sperm (Male Diagnostic tests).

If you would like more information on any of these tests and to find out if they are suitable for you, you will be able to discuss with your doctor at your consultation. We also have detailed Patient Information documents on all of our tests and treatments.

Recurrent miscarriage and implantation failure screening

We do two levels of tests to investigate possible causes of implantation failure or recurrent miscarriage. Level 1 tests rule out the more straightforward medical problems that can cause recurrent miscarriage or implantation issues. Level 2 tests are more in-depth investigations for issues like Killer cells.

Level 1 tests include:

  • an Endometrial Receptivity Array test (ERA) to pinpoint the time when the lining of your uterus is most likely to be receptive to an implanting embryo
  • The Careunity test which looks for the presence of the C4M2 gene variant which can impact on blood clotting in the placenta if inherited from the egg provider.
  • Sperm Oxidative Stress (SOS)screening to determine whether the sperm is under significant oxidative stress that can lead to DNA fragmentation

What treatments are available if the tests show something that might be affecting fertility?

We offer a range of treatment options and we specifically tailor to the findings of your own investigations.

If you would like more information on any of these tests and to find out if they are suitable for you, you will be able to discuss with your doctor at your consultation. We also have detailed Patient Information documents on all of our tests and treatments.

Call our new patient enquiry team on 0800 564 2270, they will be happy to help you get started.