Meeting abstracts from the International Stillbirth Alliance Conference 2017

Intrauterine fetal demise due to utero-placental insufficiency usually occurs between obstetric evaluations when the gestation is not being actively monitored. Rapid advances in the development of “wearable” physiologic monitors linked to smart phone apps allow us to envision novel methods for evaluating the health of a pregnancy, potentially allowing intervention before fetal death or damage from asphyxia occur. In this report, we describe efforts to develop a fetal ECG monitor that can be worn throughout the day to confirm fetal wellbeing. A wearable fabric band worn around the maternal abdomen was developed with various novel electrode materials and using various electrode placement patterns. After optimization, “in-laboratory” and overnight “athome” fetal ECG recordings were collected. The raw signal was processed to subtract interference from maternal ECG, movement, and breathing. Low-cost breathable materials and miniaturized hardware were selected to allow a comfortable fit. To date over 125 hours of fetal ECG recordings have been obtained on 38 gravidae at gestational ages from 20 weeks’ to term (mean 27 weeks’). Remarkably, over 86.7% of the overnight and 47.6% of the “in-laboratory” records tracked the fetal ECG for more than 50% of the session. Mean fetal heart rate observed was 135 (range 112-186); mean maternal heart rate was 82 (range 55111). As with prior efforts to obtain fetal ECGs, the best fetal ECG readings were obtained between 20-24 and 36-40 weeks’ gestation. Progress is reported on development of wearable fetal monitoring hardware. The “belly band” under development can connect wirelessly to a smart-phone app that monitors, analyzes, and transmits the maternal and fetal heart rates. It is hoped that improved monitoring can help to reduce preventable fetal damage and stillbirths.