Helping women with chronic heart and blood vessel problems to have safe, healthy pregnancies

Dr Jenny Myers, Dr Emma Shawkat, Dr Emma Ingram, Catherine Chmiel, Dr Ian Crocker, Dr Ed Johnstone

Researchers in Tommy’s Manchester centre are using a sensitive blood pressure machine to try and find women who are at risk of needing early delivery.

This study is now complete

Women with a history of high blood pressure have changes in the way their blood vessels work compared to women with normal pregnancies. During pregnancy, the blood flow around the body is higher because of the extra needs of the baby. Usually, women adapt to this – their blood vessels relax so that blood can pass through them more easily. In women with chronic hypertension, this doesn’t happen. This can make it more likely for women to suffer from pre-eclampsia, or for their babies to be growth restricted.

A study in the Manchester Antenatal Vascular Service (MAViS) is using a sensitive blood pressure machine to measure the stiffness of blood vessels in pregnant women. We already know that this is a much more accurate way of looking at high blood pressure in people who aren’t pregnant.

So far, over 280 women are taking part in the study. The results so far already show that measuring blood vessel stiffness in early pregnancy helps doctors to tell which women are at risk of needing early delivery. Using both measurements of blood vessel stiffness and ultrasound scans, researchers found 80% of the women who would need early delivery.

Going forward, women who are found to be at risk of needing early delivery will take part in CHERRY – the CHronic hypERtension and L-citRulline studY. This is a randomised control trial that will test the effectiveness of a drug called L-citrulline, that helps lower blood pressure.

Helping women with chronic hypertension during pregnancy is vital: the earlier doctors know who is at risk, the better they can plan for the safe and healthy delivery of the baby. There are also big economic pluses: even a 10% drop in early deliveries would save UK neonatal units around £4.2 million every year.



Research papers

  • Shawkat, E; Mistry, H; Chmiel, C; Webster, L; Chappell, L; Johnstone, ED; Myers, JE; The effect of labetalol and nifedipine MR on blood pressure in women with chronic hypertension in pregnancy. 2018 Pregnancy hypertension 11 92-98
  • Shawkat, Emma; Chmiel, Catherine; Webster, Louise; Chappell, Lucy; Johnstone, Edward; Myers, Jenny. 2018 Assessment of the added value of early pregnancy 24-h ambulatory blood pressure monitoring for the prediction of pre-eclampsia in women with chronic hypertension. 2017 Pregnancy Hypertension: An International Journal of Women's Cardiovascular Health 9 p10.
  • Myers, Jenny E; Ormesher, Laura; Shawkat, Emma; Chmiel, Catherine; Glossop, Heather; Dempsey, Alice; Ingram, Emma; Johnstone, Ed D. Arterial stiffness and placental growth factor are independent predictors of adverse pregnancy outcome in women with chronic hypertension. 2018 American Journal of Obstetrics and Gynecology. 218 S188.
  • Webster, Louise M; Myers, Jenny E; Nelson Piercy, Catherine; Mills, Charlotte; Watt Coote, Ingrid; Khalil, Asma; Seed, Paul T; Kennedy Cruickshank, J; Chappell, Lucy C. Longitudinal changes in vascular function parameters in pregnant women with chronic hypertension and association with adverse outcome: a cohort study. 2018 Ultrasound in Obstetrics & Gynecology.
  • Webster, Louise Mary; Gill, Carolyn; Seed, Paul T; Bramham, Kate; Wiesender, Cornelia; Nelson-Piercy, Catherine; Myers, Jenny E; Chappell, Lucy C. Chronic hypertension in pregnancy: the impact of ethnicity and superimposed preeclampsia on placental, endothelial and renal biomarkers. 2018 American Journal of Physiology-Regulatory, Integrative and Comparative Physiology.
  • Ormesher, L; Johnstone, ED; Shawkat, E; Dempsey, A; Chmiel, C; Ingram, E; Higgins, LE; Myers, JE. A clinical evaluation of placental growth factor in routine practice in high-risk women presenting with suspected pre-eclampsia and/or fetal growth restriction. 2018 Pregnancy hypertension.
  • Ormesher, Laura; Myers, Jenny E; Chmiel, Catherine; Wareing, Mark; Greenwood, Susan L; Tropea, Teresa; Lundberg, Jon O; Weitzberg, Eddie; Nihlen, Carina; Sibley, Colin P; Effects of dietary nitrate supplementation, from beetroot juice, on blood pressure in hypertensive pregnant women: A randomised, double-blind, placebo-controlled feasibility trial 2018 Nitric Oxide 80 37-4.
  • Shawkat, Emma; Johnstone, Edward; Chmiel, Catherine; Myers, Jenny. Relationship between night time blood pressure measured using ambulatory monitoring and markers of placental function. 2018 Pregnancy Hypertension 13 S128-S129.
  • Webster, Louise; Reed, Kate; Seed, Paul; Burns, Angela; Gupta, Pankaj; Patel, Prashanth; Wiesender, Cornelia; Nelson-Piercy, Catherine; Myers, Jenny; Chappell, Lucy; 230. Quantifying adherence to antihypertensive medication for chronic hypertension during pregnancy. 2018 Pregnancy Hypertension 13 S105-S106.
  • Ormesher, Laura; Thomas, Suzanne; Johnstone, Edward; Myers, Jenny. Is small placental biometry independent of increased uterine artery Doppler resistance for the prediction of fetal growth restriction? 2018 Pregnancy Hypertension. 13 S125.

Get our research updates

Tommy's funds research across the UK investigating the reasons for pregnancy complications and loss. We can keep you updated on our research news.  If you're interested in being kept updated about our research and news from Tommy's, click here.


This study takes place in a Tommy's centre and is funded by the National Institute for Health Research

Hide details


    Please note that these comments are monitored but not answered by Tommy’s. Please call your GP or maternity unit if you have concerns about your health or your baby’s health.

    Your comment

    Add new comment