Affecting 10 million pregnancies worldwide, this piece explores the ways preeclampsia testing is utilised to save lives, the hidden dangers of the condition and the demographics that are at most risk
The clinical symptoms, which define preeclampsia, are hypertension and proteinuria, and, in absence of the latter, maternal organ failure. Notable symptoms can include upper abdominal pain, vomiting, severe headache, and visual disturbances. All these symptoms can, at times, be difficult to identify.
Whilst the coronavirus pandemic stunted advancements in medical preeclampsia testing, recent innovations in preeclampsia research and maternal foetal health have made it easier to identify symptoms earlier in the pregnancy period.
Risks and the importance of preeclampsia testing
Preeclampsia can happen in any pregnancy. However, some factors put some people at higher risk than others. These risk factors, such as increased age, weight and some chronic diseases, are used in many countries to identify high-risk pregnancies. This approach is limited: detection of high-risk pregnancies is poor. When preeclampsia is developing, it is a life-threatening condition for the birthing parent. If left untreated, it can lead to seizures, eclampsia and even death. It is not easily diagnosed because of its non-specific symptoms resembling normal pregnancy. If the woman develops preeclampsia before 37 weeks gestation, this can result in a premature birth that has consequences for the baby’s future health and development. For this reason, cost-effective, efficient preeclampsia testing is of the utmost importance to improve maternal and neonatal outcomes.
Innovations in preeclampsia testing
PerkinElmer has innovated and collaborated with global experts in obstetrics and gynaecology, and scientific and medical communities since 2004 to identify new biomarkers for the prediction of adverse outcomes of pregnancy, including those to predict pre-term preeclampsia. Its placental growth factor assay was used in the groundbreaking ASPRE study to identify women at high risk of pre-term preeclampsia for Aspirin prophylaxis. This study demonstrated approximately 70% reduction in newborn intensive care stay for babies born at less than 32 weeks, showing the significant impact of early detection.
There are still areas that warrant additional investigation. Placental growth factor potentially has value as a marker for foetal growth restriction and stillbirth. More scientific evidence is needed to improve identification and management of these important adverse outcomes.
A more sensitive testing technique
PerkinElmer’s DELFIA Xpress PlGF 1-2-3™ was the first PlGF (Placental Growth Factor) kit developed for first trimester screening of preterm preeclampsia. PlGF is a protein present in the parent’s blood in very low concentrations during pregnancy, and when there is a risk for preeclampsia, the PIGF concentration is even lower. The highly sensitive PlGF assay was developed to maximise the detection rate possible with the first trimester prediction protocol. The higher the detection rate of the first trimester screening protocol, the more parents and babies can benefit from Aspirin prophylaxis, as demonstrated by the ASPRE RCT, with an 89% reduction in birthing parents developing preeclampsia before 32 weeks and 62% before 37 weeks. This provides a tremendous opportunity to deliver health care savings and, at the same time, protect the health of birthing parents and babies.
Disproportionate issues for Black birthing parents
Black birthing parents are twice as likely to be affected by preeclampsia during pregnancy. Whilst the mechanism is not entirely understood, there are indications that a genetic component may be involved. It is, therefore, even more important that Black birthing parents are offered first trimester screening. By starting the prophylactic treatment before 16 weeks gestation, the majority of the severe preterm preeclampsia cases can be prevented.
Future Research and Development
Looking forward, there is still a need to identify additional biomarkers to improve the detection rate from the current 75-80%, and to enable all at-risk parents to receive Aspirin prophylaxis. The International Federation of Gynecology and Obstetrics, International Society of Ultrasound in Obstetrics and Gynecology, and the International Society for the Study of Hypertension in Pregnancy have all recommended the introduction of first trimester screening for pre-term preeclampsia, but implementation of screening programmes has been impacted by the pandemic. Consequently, an increased focus on implementation is now needed globally. In some settings, the reliance of the current protocol on the measurement of mean arterial pressure and the ultrasound biomarker uterine artery doppler may be challenging, so identification of new serum biomarkers to complement PIGF may increase access to screening around the world.
Whilst pre-term preeclampsia has a significant impact on mortality and morbidity, it accounts for approximately 25% of all preeclampsia. Therefore, it is essential to identify pregnancies at risk for term preeclampsia. Many groups have failed to find a protocol for first trimester predictions of preeclampsia, and the focus has now shifted to screening at 36-weeks’ gestation, using PIGF and sFLT-1 to identify high risk pregnancies for active management. It’s a fascinating area of research and we expect to see some major developments in the next few years.
Information provided by Telle Ukonaho, Global Business Development Manager of Reproductive Health at PerkinElmer