Ophthalmic Artery and Retinal Vascular Metrics as Predictive Biomarkers for Placental Insufficiency

During pregnancy, there are dramatic changes within a women's cardiovascular system (heart and blood vessels), including a large increase in her total blood volume and redistribution of blood flow to various organs. This helps to increase the amount of blood supplying the placenta, the structure which provides oxygen and nutrients to the baby via the umbilical cord.

Sometimes this process can go awry, resulting in problems for mothers such as dangerously high blood pressure and organ damage (pre-eclampsia). Babies who do not receive sufficient oxygen and nutrition through the placenta are at risk of not growing at a healthy rate (fetal growth restriction), or even of dying inside the womb (stillbirth). Pre-eclampsia and fetal growth restriction are common reasons for babies needing to be born early, which can increase their chances of both short and long-term health problems.

Taking aspirin during pregnancy can help to improve the blood supply to the placenta in women at increased risk of these conditions. However, once pre-eclampsia or fetal growth restriction develop, the only "treatment" is for the baby to be born. Currently, we do not have reliable methods for identifying women who are most likely to develop poor placental blood supply, and it is difficult to detect problems until they are causing dangerous issues for mother or baby.

In recent years, there have been great advances in the ability of scientists to develop "digital twins". These are computational models which combine large amounts of data about an individual to create a virtual replica of biological systems and processes within that person.

During this project, I plan to collect detailed measurements from pregnant women and use these to develop personalised "digital twins" of the cardiovascular system. This will allow me to study how the blood supply to the placenta, and the distribution of blood flow throughout the body, change during pregnancy for individual participants. Women will be recruited to this study from the general population and from a specialist antenatal clinic for women affected by problems with how the placenta is functioning.

I am particularly interested in investigating how blood flow to the vessels in the retina (a structure in the back of the eye) changes at different stages of pregnancy. It is possible to take detailed pictures of the blood vessels in the retina using specialised cameras; I aim to find out whether such pictures can provide information about how a women's entire cardiovascular system (and ability to nourish her baby through the placenta) is coping with pregnancy.

This project will lead to improved understanding of what goes wrong when the placenta does not develop an adequate blood supply. My research will also allow me to develop methods to detect subtle signs of an issue, for example by picking up signals from retinal vessels and in the rest of the circulation, before the development of dangerous complications for mother or baby.

Being able to more accurately identify individuals at risk of poor placental blood supply will allow midwives and doctors to monitor pregnancies appropriately, target interventions like aspirin more effectively, and deliver babies at the safest time. This will help to reduce the harms to mothers of becoming unwell with pre-eclampsia, and the dangers for babies of being born too early or too small.