Sudden Cardiac Arrest (SCA) is a terrifying emergency in any context, but when it involves a pregnant woman, the stakes are doubled. The immediate instinct for many bystanders—and even some trained first responders – is a moment of hesitation. Is the electrical shock safe for the baby? Will the AED pads work differently?
At Practical First Aid, we specialise in providing life-saving training across London. We believe that clarity saves lives. The short answer is: Yes, you absolutely can and must use an AED on a pregnant woman.
In this comprehensive guide, we will explore the clinical guidelines, pad placement, safety protocols, and the critical importance of immediate intervention during maternal cardiac arrest.
Can You Use an AED While Pregnant?
The definitive answer from the Resuscitation Council UK, the American Heart Association (AHA), and the International Liaison Committee on Resuscitation (ILCOR) is a resounding yes.
If a pregnant woman is unconscious, not breathing, and has no pulse, she is in cardiac arrest. Without immediate intervention, neither the mother nor the foetus will survive. An Automated External Defibrillator (AED) is designed to restart the heart by delivering a controlled electric shock to stop a lethal arrhythmia.
Why Hesitation is Dangerous
The primary concern for many is the fear of “shocking the baby.” However, research and clinical practice have shown that the electric current from an AED focuses on the mother’s heart. While a small amount of current may reach the uterus, it is not considered harmful to the foetus compared to the alternative: total oxygen deprivation.
The Golden Rule of Maternal Resuscitation: You cannot save the baby if you do not save the mother. The mother’s survival is the foetus’s best and only chance at life.
Where Do You Put AED Pads on a Pregnant Woman?
One of the most common queries regarding maternal first aid is the physical application of the device. Many people wonder if the physical changes of pregnancy (enlarged breasts or a protruding abdomen) require a change in pad placement.
Standard Pad Placement
In most cases, you should use the standard adult AED pads and follow the standard placement instructions provided by the device:
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Upper Right: Place one pad on the upper right side of the chest, just below the collarbone.
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Lower Left: Place the second pad on the lower left side of the chest, underneath the breast tissue (mid-axillary line).
Modifications for Pregnancy
While the placement remains largely the same, there are two key considerations:
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Breast Tissue: If the woman’s breasts have enlarged significantly due to pregnancy, ensure the pad is placed firmly on the chest wall, not on the breast tissue itself. You may need to lift the breast to place the pad correctly.
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Avoid the Abdomen: Never place AED pads on the abdomen or near the uterus. The goal is to send the electrical current through the heart muscle.
How to Resuscitate a Pregnant Woman: Step-by-Step
Resuscitating a pregnant woman involves the standard CPR (Cardiopulmonary Resuscitation) protocol with one specific manual adjustment if you have enough rescuers.
1. Check for Response and Call 999
Tap her shoulders and shout. If there is no response, call emergency services immediately. Inform the operator that the patient is pregnant, as this may trigger a specific obstetric emergency response from the London Ambulance Service.
2. Start High-Quality CPR
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Compressions: Place your hands in the centre of the chest. Push hard and fast (100–120 beats per minute) to a depth of 5–6cm.
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Recoil: Allow the chest to fully recoil between compressions.
3. Apply the AED Immediately
As soon as an AED is available, turn it on and follow the voice prompts. Do not stop CPR while the pads are being applied; only stop when the AED tells you to “stand clear” for analysis or shock delivery.
4. Manual Left Uterine Displacement (LUD)
This is a critical “pro-tip” taught in advanced first aid courses. When a woman is past 20 weeks of pregnancy (when the bump is clearly visible), the heavy uterus can compress the Inferior Vena Cava (IVC), the large vein that returns blood to the heart, when she is lying flat on her back.
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The Technique: If a second or third rescuer is present, they should use one or two hands to gently but firmly push the uterus to the patient’s left side.
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The Benefit: This “displaces” the weight off the major blood vessels, allowing more blood to return to the heart, which makes your chest compressions significantly more effective.
What AEDs are Safe During Pregnancy?
A common misconception is that a special “maternal AED” is required. This is not the case.
All standard UK-approved AEDs are safe for use on pregnant women. Whether you are using a Zoll, Philips, Lifepak, or Heartsine device, the technology is universal.
Key Features to Look For:
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Adult Pads: Ensure you are using adult pads. Paediatric (child) pads should never be used on a pregnant woman, as the energy level is too low to effectively restart an adult heart.
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Clear Voice Prompts: In a high-stress situation, a device with clear, calm instructions is invaluable.
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Automatic vs. Semi-Automatic: Both are safe. An automatic AED will deliver the shock itself, while a semi-automatic will ask you to press a button.
Common Causes of Cardiac Arrest in Pregnancy
Understanding why maternal cardiac arrest happens can help in providing better information to emergency services upon their arrival. While rare, causes include:
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Haemorrhage: Severe bleeding.
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Amniotic Fluid Embolism: When amniotic fluid enters the mother’s bloodstream.
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Preeclampsia/Eclampsia: Related to high blood pressure.
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Pre-existing Cardiac Conditions: Conditions that may be exacerbated by the physical stress of pregnancy.
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Sepsis: Severe infection.
The Importance of Training: Why London Businesses Need First Aid Courses
While reading an article is a great first step, nothing replaces the hands-on experience of a certified first aid course. At Practical First Aid, we provide comprehensive training across London that covers:
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Confidence Building: Overcoming the “fear factor” of using an AED on a pregnant woman.
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Practical Skills: Learning the Left Uterine Displacement (LUD) technique.
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Regulatory Compliance: Ensuring your workplace meets HSE requirements.
Whether you are a teacher, an office manager, or a fitness professional in London, being prepared for a maternal emergency is a vital skill.
FAQs: AED Use and Pregnancy
Will the shock restart the baby’s heart?
The AED is designed to analyse the rhythm of the mother’s heart. While the shock is intended for the mother, the restoration of maternal circulation is the only way to ensure oxygenated blood reaches the baby.
Can you use an AED while pregnant?
Yes. If a pregnant woman is in cardiac arrest, an AED is safe and essential. The electrical current focuses on the mother’s heart, and her survival is the foetus’s only chance at life.
Where do you put AED pads on a pregnant woman?
Use standard adult placement: one pad on the upper right chest below the collarbone and the other on the lower left chest wall, ensuring it is placed under the breast tissue if necessary. Never place pads on the abdomen.
How to resuscitate a pregnant woman?
Resuscitation involves high-quality chest compressions (100–120 bpm), immediate AED use, and manual Left Uterine Displacement (LUD) to move the uterus to the patient’s left side to improve blood return to the heart.
What AEDs are safe during pregnancy?
All standard UK-approved AEDs (such as Zoll, Philips, or Heartsine) are safe for use on pregnant women. Always use adult pads rather than paediatric pads to ensure sufficient energy delivery.
The Bottom Line
The most important takeaway is this: An AED cannot make the situation worse for a woman in cardiac arrest. She is already in a life-threatening state. By using the AED, you are giving her and her unborn child the only possible chance of survival.
Do not be afraid of the technology. AEDs are “smart” devices; they will only deliver a shock if the patient’s heart rhythm requires it. If you see a pregnant woman collapse, remember: Call 999, start CPR, and use the AED.
Get Trained with Practical First Aid
Are you based in London or the surrounding areas? Don’t leave safety to chance. Practical First Aid offers bespoke training sessions that give you the skills and confidence to handle any emergency, including maternal cardiac arrest.
