Fetal magnetocardiography (fMCG): moving forward in the establishment of clinical reference data by advanced biomagnetic instrumentation and analysis.

Cardiotocography and echocardiography are currently standard for fetal heart monitoring. However, both do not provide adequate temporal resolution to measure fetal cardiac time intervals and detect arrhythmias, which can occur during normal sinus rhythm. Fetal magnetocardiography (fMCG) is a non-invasive technique measuring magnetic signals generated by fetal heart activity. Most fMCG devices are installed in research institutions limiting the implementation of this method in a clinical setting. Several institutions made a step forward by installing devices, in particular for fetal investigations, in hospital sites to evaluate the clinical benefit. Based on instrumentation differences which can affect signal quality, there is still no established reference database for fetal cardiac time intervals. A new magnetograph dedicated to fetal recordings was implemented with improved patient comfort. The setting was optimized to establish a standard. A total of 103 healthy fetuses starting as early as possible after the first trimester were recorded and fMCG values of cardiac time intervals were compared to former studies. Data allowed high and reliable detection for all fMCG components starting at 17 weeks. The data were comparable to fMCG multicenter studies, fetal electrocardiography and neonatal ECG results and could serve as a database of norm values for further investigation of fetal arrhythmias.