NI-fECG and STE: 16-28 weeks gestational age.

Background: Common complications during pregnancy are hypertensive disorders of pregnancy (HDP), fetal growth restriction (FGR), and premature birth. These complications are important causes of maternal and neonatal mortality and long term morbidity. Pregnancies complicated by HDP are believed to be initiated by placental dysfunction. Placental dysfunction can result in FGR. As a result, the normal growth and development of the fetus and neonate is endangered. In the process of fetal adaptation to placental insufficiency, the fetal heart has a major role. Even subtle cardiac changes would be responsible for a worse perinatal outcome. Threatened preterm birth is likely associated with a change in uterine cell excitability, favoring conduction of electrical activity across the uterine muscles. Ante partum assessment of the cardiac function and uterine activity is therefore essential for the evaluation of pregnancies complicated with a PRD. Even though several diagnostic tools have been used to predict these PRD, unfortunately none of these tests have been successful. Promising new tools in the prediction of the aforementioned pregnancy related diseases (PRD) are the Nemo Fetal Monitoring System® (NFMS) and two-dimensional speckle tracking echocardiography (2D-STE). However, in order to determine PRD, it is first needed to determine physiological changes during pregnancy using the NFMS and 2D-STE. Reference values can then be established in uncomplicated pregnancies. A part of this cohort will develop PRD. The NFMS and 2D-STE parameters of these complicated pregnancies can then be compared with the reference values to investigate whether the PRD can be predicted.

Objective: The primary objective of this study is to generate reference values for NFMS parameters as well as for 2D-STE parameters during the second trimester, 16 until 28 weeks gestational age. The secondary objective is to investigate the diagnostic potential of NFMS parameters and 2D-STE parameters to detect PRD in the second trimester, before they become aberrant, to examine if we can predict pregnancies that are at high risk for PRD at a very early stage of pregnancy using NFMS and / or 2D-STE parameters.

NFMS (NIFECG and EHG) parameters are associated with HPD, IUGR and preterm birth and can help detect these diseases during early gestation.

Fetal heart deformation will be analysed 4-weekly at 16, 20, 24 and 28 weeks gestational age using 2D-STE. NFMS recordings will be made weekly from 22 until 28 weeks gestational age.

Longitudinal prospective cohort design. Subjects will be recruited at their first antenatal consultation before 16 weeks gestational age. Fetal heart deformation will be analysed 4-weekly at 16, 20, 24 and 28 weeks gestational age using 2D-STE. NFMS recordings will be made weekly from 22 until 28 weeks gestational age to obtain all parameters of the cardiotocogram (CTG), fetal electrocardiogram, electrohysterogram (EHG) and maternal electrocardiogram. Data will be analysed using specified software. Follow-up ends 6 weeks after delivery.
Population: Pregnant women with a singleton pregnancy at 16 weeks gestational age will be included to the prospective cohort. Retrospectively, the PRD group (women who develop a PRD from the start of the measurements until birth) will be compared with the healthy control group. PRD is defined as: HDP, FGR and preterm birth.