Which combination of sleep-related factors is a risk factor for SIDS?

• A. Alcohol use
• B. Breastfeeding
• C. Side/prone sleeping and bed sharing
• D. Bed sharing

Answer: (C)

Combining how a baby sleeps with the sleep surface they share greatly increases the risk of SIDS. When a baby is placed on his or her side or stomach, their airway is more vulnerable and their reflexes to wake or reposition can be diminished. Sharing a sleep surface with an adult adds another hazard—there’s a higher chance of suffocation, overlay, or entrapment on a soft mattress, with loose bedding, pillows, or blankets. Put together, side or prone sleeping with bed-sharing creates a high-risk scenario far beyond either factor alone, which is why this combination is a well-recognized risk for SIDS. Breastfeeding, by contrast, is associated with a lower risk, and bed-sharing by itself is risky but does not capture the amplified danger that comes from combining sleep position with sharing a surface.