Thousands of pregnancies to be tracked in UK's biggest study on pre-eclampsia

Up to 3,500 first time moms are due to take part in a study led by Cambridge researchers to understand why some will develop pre-eclampsia and placental complications during pregnancy and whether it effects their long-term health.

The POPPY study (Preconception to pOst-partum study of cardiometabolic health in Primigravid PregnancY) is being led by a team from Cambridge University Hospitals NHS Foundation Trust (CUH) and the University of Cambridge. The study is also being carried out in Glasgow and up to four other research centers in London.

In the first large scale study of its kind in the U.K., women are being monitored before, during and after their first pregnancy to see what factors might be influencing the health of their placenta and their long-term cardiovascular risk. It's hoped that by understanding this risk, the health of women who develop placental complications can also be improved over their lifetime.

Placental complications affect about 1 in 10 pregnancies and includes:

• pre-eclampsia (high blood pressure with kidney/liver/brain involvement)
• gestational hypertension (high blood pressure in pregnancy)
• fetal growth restriction (baby being small).

These conditions can lead to serious complications for both mother and baby if not monitored or treated.

High blood pressure (hypertension), diabetes, autoimmune conditions, age and being obese before pregnancy are just some of the factors likely to increase the risk of pre-eclampsia and placental dysfunction, but it's unclear exactly why and whether there are other causes.

In addition, women who experience placental complications are twice as likely to develop heart disease and diabetes later in life, compared with women who have a healthy pregnancy.

It's not clear however whether placental complications cause heart disease and diabetes directly, or whether these conditions happen in women who already have some underlying and/or unknown health issues before pregnancy.

Women thought to be at high risk of developing pre-eclampsia are advised to take a 75 to 150mg daily dose of aspirin from the twelfth week of pregnancy until birth to reduce the risk of developing this condition. If a woman develops pre-eclampsia, the only way to cure it is to deliver the baby, normally at around 37 to 38 weeks of pregnancy, although this can be earlier in more severe cases.

Dr. Bernadette Jenner is a medical registrar in obstetric medicine and clinical pharmacology at Cambridge University Hospitals NHS Foundation Trust (CUH) and is leading the POPPY study in Cambridge. She said, "This study is going to be monitoring thousands of women from before they become pregnant for the first time and will track them through to birth and beyond to try and discover why some develop placental conditions and others don't. We also hope to find out whether or not these conditions trigger longer-term health issues such as heart disease and diabetes.

"We have a significant lack of understanding when it comes to placental conditions, especially when you consider how common they are, and the serious impact they can have on women and babies, which at times is life-threatening. To prevent pre-eclampsia and other placental conditions we need to know what really causes them and why. We have some big gaps in our knowledge and this study hopes to find answers."

Professor Ian Wilkinson is leading the POPPY study and is a clinical pharmacologist and Professor of Therapeutics at the University of Cambridge. He said, "The POPPY study is a world first and will help us to better understand why common complications of pregnancy adversely affect women's long term cardiovascular health. This is the key to reducing this risk and may also allow us to prevent pregnancy complications before they occur.

"Unfortunately, many women who suffer from pre-eclampsia, or one of the other placental complications, are not aware of the potential long term risks, and very few of them are actively followed up after birth—despite recommendations by NICE.

"Therefore, whilst we await the findings of the POPPY study it is important that women who have experienced one of these complications are seen by a medical professional in the months after delivery to ensure that their blood pressure and other cardiovascular risk factors are checked and treated if necessary."

The POPPY study is now open at Addenbrooke's Hospital in Cambridge. Two more sites will be open soon at Glasgow Royal Infirmary NHS and Imperial College Healthcare NHS Trust, with further sites in London to start in the coming months.

Participants must be planning their first pregnancy and live in Glasgow, Cambridge or London where the study is taking place. Participation will involve monitoring alongside regular pregnancy checks and tests.

Find out how you can take part on the POPPY Study website.

Provided by University of Cambridge