Preeclampsia in Fetal Medicine

Preeclampsia is one of the most serious diseases in pregnancy affecting 2 – 8 % of all pregnancies. Fetal morbidity and mortality are increased due to severe maternal multisystem complications such as maternal liver or renal failure combined with cardiovascular, cerebral, hematological or pulmonary impairment. Regarding the frequent and severe maternal and fetal complications, many efforts are necessitated to predict preeclampsia [1] [2] [3].

For many years the main aim of various studies was to prevent this disease. In the last 5 years, research in feto-maternal medicine is additionally focused on prediction of preeclampsia. Recent research is targeting to establishing screening strategies for preeclampsia based on biochemical markers, maternal medical history, mean maternal arterial blood pressure and uterine artery Doppler ultrasonography. The aim is to implement a risk assessment program for a disease with a manifestation occurring months later [4] [5] [6].

Gallo, et al. [7] reported in 2013 that the measurement of pulsaltility indices of A. uterinae with ultrasound at second trimester could predict preeclampsia up to 72 %. It was shown that a similar measurement at first trimester between 11 + 0 to 13 + 6 weeks of pregnancy can predict an early onset preeclampsia before 34 weeks of pregnancy with a detection rate of 89 % and false positive rate 10 %, when combined with the measurement of mean arterial pressure [8]. The study group of Nicolaides [8] developed a prediction model for early-onset preeclampsia combining the maternal history with biochemical and biophysical markers such as the pulsaltility indices of A. uterinae. This model can predict an early onset preeclampsia with a detection rate of 95 % and false positive rate of 11 % [9] [10].

A good and accurate prediction of this condition in a combined screening-manner at the same timeline with first trimester screening for chromosomal abnormalities can help the clinician to decide with the patient to start a prophylactic therapy with acetylsalicylic acid (Aspirin) at a dosis of 150 mg before the 16 weeks of pregnancy [11] [12]. According to the latest prospective randomised multicentral trial (ASPRE Study) [11], it has been reported that this prophylactic therapy started before the 16 weeks of pregnancy can prevent early-onset preeclampsia up to 82 % before 34 weeks of pregnancy and 62 % before 37 weeks of pregnancy.

There is still a big gap to fill on research for late-onset preeclampsia, where the combined screening models as in first trimester but also second and third trimesters with uterine artery Doppler and biomarkers like soluble fms-like tyrosine kinase-1 and placental growth factor may rule out the condition for a week, yet cannot predict the upcoming disease with a high specificity. The study groups throughout the world work on finding new biomarkers or ultrasound measurements which could be related to the pathophysiology of the disease. There are also national and international discussion groups to implement the screening models in local medical systems or to find out which measurement could be the optimal way to follow-up the high-risk group of patients.

The latest research helps us to predict not only preeclampsia, but also other placenta-related conditions like intrauterine growth retardation or morbidly adherent placenta. These conditions as well as preeclampsia should also be a central part of our field as physicians working on fetal medicine and there is still a long way to get better in predicting, preventing and hopefully treating these conditions in the future. We should be aware that we are still far away to explain the medical syndrome preeclampsia and yet must support every possible good research project run on a way from diagnosis to therapy. Is it also the right time to offer universal screening for preeclampsia for all patients?

Cahit Birdir

Sevgi Tercanli

• References

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• 3 National Collaborating Centre for Women’s and Children’s Health (UK). Hypertension in pregnancy: the management of hypertensive disorders during pregnancy. London: RCOG Press; 2010
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