Development of a comprehensive database for research on foetal acidosis

Objective: To develop a research database for mother-and-child clinical and laboratory data and digital foetal heart rate (FHR) recordings.

Methods: The Base Bien Naître (BBN) database was derived from a single-centre health data warehouse. It contains exhaustive data on all parturients with a singleton pregnancy, a vaginal or caesarean delivery in labour with a cephalic presentation after at least 37 weeks of amenorrhea, and a live birth between February 1st, 2011, and December 31st, 2018. On arrival in the delivery room, the FHR was recorded digitally for at least 30 min. A cord blood sample was always taken in order to obtain arterial pH (pHa). More than 6,000 recordings were analyzed visually for the risk of foetal acidosis and classified into five groups (according to the French College of Gynaecologists and Obstetricians (CNGOF) classification) or three groups (according to the International Federation of Gynaecology and Obstetrics (FIGO) classification).

Results: Of the 16,089 files in the health data warehouse, 11,026 were complete and met the BBN's inclusion criteria. The FHR digital recordings were of good quality, with low signal loss (median [interquartile range]: 7.0% [4.3;10.9]) and a median recording time of 304 min [190;438]). In 3.7% of the children, the pHa was below 7.10. We selected a subset of 6115 records with good-quality FHR recordings over 120 min and reliable cord blood gas data: 692 (11.3%) had at least a significant risk of acidosis (according to the CNGOF classification), and 1638 (26.8%) were at least suspicious (according to the FIGO classification).

Conclusion: The BBN database has been designed as a searchable tool with data reuse. It currently contains over 11,000 records with comprehensive data.