A pregnant woman with short blonde hair stands in her living room with one hand on her bump, while making a phone call.

Maternity pre-arrival instructions by 999 call handlers


The national investigation

This national investigation explores factors influencing the instructions 999 call handlers give to women and pregnant people who have called 999 because of an emergency during their pregnancy and are waiting for an ambulance to arrive. These instructions are known as ‘pre-arrival instructions’.

Pre-arrival instructions are generated by a clinical decision support system (CDSS). There are two CDSS in use by ambulance services in England. One is an international system, and one is a UK-based system. Both systems have protocols for identifying the required response to urgent and emergency situations, including maternity issues.

Our national investigation was launched after similar concerns were identified in 15 HSIB maternity investigations. They all involved pre-arrival instructions generated by a CDSS. In each case the CDSS had generated pre-arrival instructions that had the potential to cause harm to the woman or pregnant person and/or their baby.

Reference event

The reference event in this investigation involves Amy, who was 39 weeks and 4 days pregnant with her first child. She contacted 999 after experiencing abdominal cramps and bleeding.

While waiting for an ambulance to arrive, Amy received pre-arrival instructions which were generated through a clinical decision support system (CDSS) from a non-clinical call handler. Amy was then taken by ambulance to hospital where her baby, Benjamin, was delivered by emergency caesarean section.

Amy had excessive blood loss due to a placental abruption and was admitted to the high dependency unit for 12 hours following the birth. Benjamin required resuscitation to help him breathe on his own, he was intubated, and he received 72 hours of therapeutic cooling. He spent 13 days in hospital.

Investigation summary

The investigation report is intended for healthcare organisations, policymakers and the public to help improve patient safety in relation to the instructions 999 call handlers give to women and pregnant people who are waiting for an ambulance because of an emergency during their pregnancy.

The investigation report:

  • Identifies the systemic factors influencing 999 call handler pre-arrival instructions.
  • Explores both the UK and international clinical decision support systems (CDSS) in relation to alignment and consistency of pre-arrival instructions with UK and international guidance.
  • Considers national regulation and governance mechanisms for CDSS content.