Continuous Non-invasive Electrophysiological Monitoring in High Risk Pregnancies

The goal of this single centre cohort intervention study with historical controls, is to investigate the effect of implementing continuous antepartum electrophysiological CTG (eCTG) monitoring at the Obstetric High Care (OHC), on perinatal and maternal outcomes and obstetric care.

The main aim is to investigate the effect of both monitoring methods on:

* primary outcome: perinatal outcomes (a composite of perinatal mortality or major neonatal morbidity) until hospital discharge
* secondary outcomes: Maternal mortality, neonatal morbidity, satisfaction for both patient and caregiver, duration of pregnancy, switch of monitoring method, duration of admission to the OHC, timing (planned or emergency) and number of obstetric interventions (such as caesarean section), and admission and duration of admission to the NICU (neonatal intensive care unit).

Eligible women will be prospectively included in the cohort receiving standard treatment: CTG monitoring intermittent up to three times a day. From these eligible women, a random sample (464) of the prospective cohort (511) will be offered to receive a new monitoring method: 24/7 eCTG monitoring. In order to strengthen the comparison between the two groups (eCTG and standard treatment), additional data from 1400 women who received standard treatment in 2014-2019 will be collected retrospectively.

Pregnant women in need for maternal and/or fetal monitoring are hospitalized at the obstetric high care (OHC) of Máxima Medical Center (MMC). They are monitored for up to three times a day with conventional cardiotocography (CTG). In the meantime they reside at the OHC, but the status of the fetus and uterine activity (UA) is not monitored. Nemo Healthcare developed a wireless abdominal electrode patch for measuring fetal heart rate (FHR) and UA: The Nemo Fetal Monitoring System (NFMS). Previous research on non-invasive electrophysiological CTG (eCTG) has yielded promising results in monitoring FHR and UA both during pregnancy and labor. With the use of eCTG technology, safe continuous 24/7 monitoring is possible, which is not possible with conventional cardiotocography. The investigators hypothesize that by introducing continuous antepartum eCTG monitoring perinatal and maternal outcomes will improve.

The investigators aim to include 1911 pregnant women ≥18 years old with a singleton pregnancy between 23+0 and 32+0 weeks of gestation requiring hospitalization on the OHC for maternal or fetal surveillance (including 1400 historical controls).

Additional objectives: The collected NFMS and demographic data will be used to develop and verify a mathematical model for the prediction of time until (preterm) birth, which may be used in clinical practice to reduce unnecessary OHC admissions and facilitate a better timing of interventions. Furthermore, data collected in this study (NFMS, accelerometric, annotated ultrasound) will be used for the development and verification of a mathematical model for the automated detection of fetal movements in NFMS data. This latter model might provide new opportunities in non-invasive monitoring of fetal health.

Eligibility Criteria:
Inclusion Criteria:

* ≥18 years old
* Singleton pregnancy ≥23+0 weeks of gestation
* Requiring hospitalization to the OHC for maternal or fetal surveillance (i.e. imminent preterm delivery(PPI), PE, HELLP, pregnancy induced hypertension (PIH), FGR, fetal distress, vaginal blood loss, fetal congenital anomalies)
* Parents wishing for fetal monitoring

Exclusion Criteria:

* Multiple pregnancy
* Insufficient knowledge of Dutch or English language
* Contraindications to abdominal patch placement (dermatologic diseases of the abdomen precluding preparation of the abdomen with abrasive paper)
* Women connected to an external or implanted electrical stimulator (e.g. a pacemaker - exclusion due to possible signal interference)
* Fetal and/or maternal cardiac disease (i.e. arrhythmia, congenital defect)
* Treatment plan (with intervention planned within 24 hours after admission) already made before inclusion is completed
* Women admitted with a clinical diagnosis of sepsis with hypotension (i.e. septic shock).