Why do we need this research?
A successful pregnancy relies on the placenta functioning properly. If the placenta does not develop as it should or is damaged later in pregnancy, there is a higher chance that a woman or birthing person will experience complications that can lead to stillbirth, such as slow fetal growth or pre-eclampsia.
Right now, we do not have a test that can reliably predict whether the placenta is failing, and by the time pregnancy complications appear, there are no treatments that can reverse them. Having a reliable predictive test would mean that doctors could intervene at an earlier stage before these problems occur, which could help to prevent stillbirth.
What’s happening in this project?
Our scientists have been finding out what a hormone called placental growth factor (PlGF) can tell us about the health of the placenta. Already, women and birthing people who are suspected of having pre-eclampsia can have a test to measure the amount of PlGF in their blood, with low levels indicating that they have the condition. Low levels of PlGF can also occur when the baby is growing slowly in the womb or in pregnancies that end in stillbirth. However, little is known about why PlGF levels are low in these pregnancies and what this tells us about the health of the placenta. It is likely that there are many different reasons for a low PlGF result, meaning that one single treatment would not prevent further complications for all women and birthing people with low PlGF.
Our team found that low levels of PlGF in the blood can occur because the hormone has bound to another molecule – called sFlt-1. However, this may not be the only cause of low PlGF levels – the team also found that some placentas simply don’t produce enough PlGF. Interestingly, the researchers found that the placenta is still able to deliver nutrients to the baby effectively, even when PlGF levels are low.
To find out more about how the placenta is working in pregnancies where low PlGF levels have been detected, our researchers also carried out genetic analysis of the cells in the placenta to see which genes were active and which substances were being produced. They identified two different placenta subtypes associated with low PlGF levels and think that the causes of the placenta problems are different in the two groups. This means that any treatments that are developed in the future may not be effective for all women and birthing people with low PlGF levels, and so personalised treatment may be required.
What difference will this project make?
We now understand more about the causes of low PlGF levels and what this finding tells us about the health of a woman or birthing person’s placenta. This work lays the foundations for the development of tests that could tell how well the placenta is working in pregnancy, and could also lead to the development of new, personalised treatments that prevent pregnancy complications from occurring.
