The Early Pregnancy Observational Study (EPOS): following women throughout pregnancy to understand miscarriage

In order to understand miscarriage better, Tommy’s researchers have followed over 1,500 pregnant women throughout pregnancy. They have collected a huge amount of information from these women and are now using this to find ways of predicting the chances of miscarriage.
  • Authors list

    Professor Tom Bourne, Professor Phillip Bennett, Dr David MacIntyre, Dr Maya Al-Memar, Professor Christoph Lees, Dr Margaret Pikovsky

    Start date: 2016    
    End date: 2024

Why do we need this research?

We still don’t know enough about why miscarriage happens, which means that many women and birthing people are not given a reason for their loss or an indication of how likely it is to happen again in the future.

We need better tests to accurately predict the chances of miscarriage.

What’s happening in this project?

For several years, our researchers have been asking women to take part in The Early Pregnancy Observational Study (EPOS). As well as recording information about each woman’s clinical history and the outcome of their pregnancy, the researchers collect blood, urine and vaginal samples from the women throughout their pregnancies. So far, this study has followed more than 1,500 women from five weeks of pregnancy through to miscarriage or birth, enabling our team to collect a vast amount of data.

By working with so many women, our researchers have been able to find out more about miscarriage. For example, the team discovered that women who miscarry are more likely to have an imbalance of bacteria in their vagina, and now they want to use the EPOS platform to find out whether treatment with probiotics can correct this and prevent miscarriage. They also found that a hormone called kisspeptin is present in lower levels in women who eventually miscarry. Our researchers have used these, and their other findings, to build models that can be used to predict the chances of miscarriage, and now want to find out whether the use of these models has a psychological impact on women.

Our researchers also want to use EPOS to continue their search for a simple test that can tell if a miscarriage happened because of a genetic abnormality. They will do this by studying cell-free fetal DNA – DNA from the baby that is shed from the placenta into the mother’s blood – at the time of miscarriage. As an additional focus, the team are using data from EPOS to find out more about whether COVID-19 infection during pregnancy can lead to miscarriage or other complications later in pregnancy.

Finally, the team are now carrying out EPOS-2, which will validate the findings of the original EPOS project in an even larger group of women. EPOS-2 will focus on the earliest stages of pregnancy – before it is even possible to assess the viability of a pregnancy on an ultrasound scan and when interventions to prevent miscarriage are most likely to be effective.

What difference will this project make?

Our researchers believe that the EPOS platform will help them to understand why miscarriage happens, and hope that their predictive model can be validated and eventually introduced into clinical practice. This could lead to problems being detected earlier, enabling healthcare providers to give the best possible care, and allowing women, birthing people and their families to prepare emotionally for the possibility of having a miscarriage.

Thanks for your interest in our research

Tommy's funds research across the UK investigating the reasons for miscarriage, stillbirth and premature birth. We can keep you updated on ways you can support our work. If you would like to join our fight against baby loss and premature birth, click here.