Research published in the American Heart Association journal, Hypertension, suggests that using a new screening algorithm for preeclampsia may help in identifying more cases in the first trimester of pregnancy. This new method combines maternal history, ultrasound data, and various blood marker tests to better predict cases of preeclampsia, which could potentially be preventable during the early stages of pregnancy. Preeclampsia is known to be the most dangerous form of high blood pressure during pregnancy.Preeclampsia is a serious condition characterized by high blood pressure (usually above 140/90 mm Hg) during pregnancy, and it is a major cause of maternal mortality globally. When left untreated, preeclampsia can be life-threatening. It affects approximately 1 in 25 pregnancies in the U.S., and it is more common in first-time pregnancies. Symptoms of preeclampsia include headaches, changes in vision, and swelling of the hands, feet, face, or eyes of the mother, as well as changes in the baby’s well-being. Recent research has shown that preeclampsia can increase the risk of developing cardiovascular complications for women later in life.
“Preeclampsia is one of the most serious pregnancy-related illnesses and can result in premature birth and/or the death of the mother,” said the lead researcher.Author Emmanuel Bujold, M.D., M.Sc., a professor in the department of obstetrics and gynecology at the Université Laval in Québec City, Canada, stated that the biological processes leading to preeclampsia typically begin in the first trimester of pregnancy (weeks 1 through 12). However, the initial symptoms of preeclampsia usually do not appear until week 20.
According to Bujold, the current guidelines from the American College of Obstetricians and Gynecologists (ACOG) suggest that pregnant women should take aspirin if they have a major risk factor, such as chronic high blood pressure, Type 2 diabetes, or chronic kidney disease.ACOG recommends aspirin for pregnant women with certain risk factors such as a history of chronic hypertension, diabetes, kidney disease, autoimmune diseases like antiphospholipid syndrome, systemic lupus erythematosus, or type 1 diabetes, or preeclampsia in a prior pregnancy. ACOG also recommends aspirin for pregnant women with two moderate risk factors such as being a Black woman, having a sister or mother with a history of preeclampsia, having a first pregnancy, obesity, or an IVF pregnancy.
According to Bujold, following these guidelines, almost all Black women should take aspirin during pregnancy, as should about one-third of all women of other races and ethnicities.
Previous studies from the Fetal Medicine Foundation have shown that preterm preeclampsia, which is defined as developing preeclampsia before 37 weeks of gestation, can be predicted in the first trimester.In a recent study, researchers examined the effectiveness of the Fetal Medicine Foundation’s screening model for detecting preeclampsia in pregnant women during their first trimester. Over 7,000 first-time pregnant women in Canada, who were between 11 and 14 weeks pregnant, were involved in the study. The screening model included maternal history, ultrasound data, and various blood marker tests.
The study’s findings revealed that for participants between 11 and 13 weeks of pregnancy, the Fetal Medicine Foundation’s screening model resulted in a 63.1% detection rate for preterm preeclampsia (before 37 weeks of gestation).77.3% of cases were detected for early preeclampsia (before 34 weeks of gestation) with a false positive rate of 15.8%. According to the risk factor-based guidelines from the American College of Obstetricians and Gynecologists, the detection rate for preterm preeclampsia would be 61.5% and 59.1% for early preeclampsia, with a false-positive rate of 34.3%. This is more than twice the false-positive rate of the Fetal Medicine Foundation’s screening model.
Once preeclampsia has developed, the only way to resolve it is to deliver the baby. A previous meta-analysis by the study authors found that taking one low-dose aspirin daily may reduce the risk.A new screening model has been developed to help reduce the risk of developing preeclampsia by up to 53%. Treatment decisions are now based on each individual’s personal risk, making it easier for women to make informed choices. For example, those at higher risk may choose to take daily low-dose aspirin, leading to higher compliance due to personalized screening results. The study was conducted between 2014 and 2020 at five health centers across Canada, where universal health coverage is available to all citizens.<s and permanent residents.
- 7,554 first-time pregnant women were included in the study at 11-14 weeks of pregnancy. Of those, 7,325 remained eligible for the final analysis after delivering after 20 weeks, while 229 were excluded due to fetal anomalies.
- Upon enrollment, participants were screened for preeclampsia and data on age, weight, ethnicity, smoking status, and chronic health conditions were collected, including chronic hypertension, Type 1 or Type 2 diabetes, and antiphospholipid syndrome, an autoimmune disease associated with pregnancy complications.The participants in the study had an average age of 29 years. 92% of them identified as white, while 4% identified as Black, 2.6% as South Asian, 0.9% as East Asian, 0.3% as First Nations, and 0.2% as mixed race or undetermined. The study excluded women who were taking antihypertensive medication for chronic hypertension, as well as those taking low-dose aspirin or low-molecular-weight-heparin (a blood thinner) on a daily basis. Participants were followed until delivery, with the primary outcome being preterm preeclampsia and the secondary outcome being early preeclampsia. Out of the 7,325 women included in the analysis, 65 (0.9%) developed preterm preeclampsia, and 22 (0.3%) developed early preeclampsia.
The study had some limitations, as it did not include several women with risk factors for preeclampsia, such as high blood pressure and Type 2 diabetes before pregnancy, if they were already taking aspirin for preeclampsia prevention. This made it difficult to determine whether this population would rely solely on the Fetal Medicine Foundation’s screening model to decide whether or not to take daily, low-dose aspirin, Bujold noted. Additionally, only one lab was used to analyze blood samples, and blood samples.The blood samples collected at various centers in Canada were frozen and sent for analysis, resulting in a delay of several weeks between the blood draw and the biomarker measurement. This delay may have impacted the results.
“Including the entire population and analyzing the blood samples immediately could have potentially improved the screening process,” Bujold suggested. “Implementing a screening program in major cities throughout North America could further enhance the accuracy of the screening process.” “The positive news is that we now have a more accurate screening method using existing tests to predict preeclampsia at an early stage.”pregnancy. The next step is to ensure that all pregnant women have access to this screening so that more women can be diagnosed early in pregnancy and start taking preventive aspirin, potentially avoiding complications from severe preeclampsia.”
According to Sadiya S. Khan, M.D., M.Sc., FAHA, who led the writing group for the Association’s 2023 scientific statement on Optimizing Prepregnancy Cardiovascular Health to Improve Outcomes in Pregnant and Postpartum Individuals and Offspring, the goal and priority of predicting the risk for term and preterm preeclampsia remains important for improving maternal health and addressing disparities. Khan
Dr. Khan holds the Magerstadt Professor of Cardiovascular Epidemiology and is an associate professor of medicine and preventive medicine at the Northwestern University Feinberg School of Medicine in Chicago. Additionally, she is a preventive cardiologist at Northwestern Medicine.
According to Khan, “Given that the risks for preeclampsia are heavily influenced by pre-pregnancy health, a screening model that can be used in early pregnancy is extremely beneficial. It can also kickstart conversations between the clinician and patient about strategies to improve heart health. However, there are still challenges in implementing models like this one that incorporate biomarkers.”
The availability of routine assessments for preterm preeclampsia may be limited, especially among vulnerable populations at high risk for the condition.
