TraCer (TransCerebellar diameter) project

Accurate knowledge of gestational age (GA) is a cornerstone of modern maternity care, reducing unnecessary interventions while reducing stillbirths and other obstetric complications. In most LMICs, many women never receive antenatal care or, if they do, present at 20wks gestation or later10. Pregnancy dating using either maternal recall of her last menstrual period or symphysis-fundal height is inaccurate10-14. Although U/S is the most accurate approach, lack of expensive equipment and trained staff means accurate GA dating is often unavailable in LMICs despite its obvious need.

We have developed a mobile health (mHealth) and image analysis US platform for automated measurement of the fetal transcerebellar diameter (TCD); this measurement correlates with GA and, in the absence of fetal anomalies, is relatively protected from the influence of FGR and remains reliable throughout pregnancy15. SGUL and Oxford have jointly embarked on the TraCer initiative: to develop and validate automated image recognition and measurement software to capture the TCD during an U/S examination by minimally-trained health workers.


To enumerate the prevalence of pregnancy hypertension, accurate blood pressure (BP) measurement is essential. In LMICs, pre-eclampsia is frequently undetected as there is low attendance for antenatal care, inadequate training in BP measurement, and insufficient, poorly functioning equipment. Led by Professor Shennan at KCL, and with Gates and MRC funding a clinically validated a semi-automated BP device (Microlife CRADLE Vital Signs Alert (VSA®)) has been developed specifically for use in LMICs (see image on upper right), including pre-eclampsia). The device comprises a micro-USB port and a sealed rechargeable Li battery pack for charging through generic mobile phone chargers. The manual inflation prolongs battery life. An integrated traffic-light early warning system alerts users to BP abnormalities. Predefined BP thresholds, used as hypertension triggers for the CLIP Trials (see image on lower right [Accredited Social Health Activist (ASHA) using the CRADLE device during a home visit in India]) have been introduced as the amber and red triggers within the traffic light system. As well as being a highly accurate device suitable for LMIC settings, this device costs less than $20 USD, and was named by Innovation Countdown 2030 as one of 30 high impact innovations to save lives.