In the third trimester, which positioning is recommended during dental treatment?

• A. Supine
• B. Left lateral tilt with soft support
• C. Right lateral tilt
• D. Standing upright

Answer: (B)

When a patient is in the late stages of pregnancy, lying flat can press the uterus against the large vein that returns blood to the heart (the inferior vena cava). This compression can lower maternal blood flow and fetal oxygen delivery, causing dizziness for the patient and potential distress for the fetus. The best way to avoid this is to tilt slightly to the left side and support the right hip with a soft cushion or pillow. This left lateral tilt moves the uterus off the vena cava, improves venous return, and preserves stable blood flow to both mother and baby while still allowing the dentist to work comfortably.

Standing upright isn’t practical for dental treatment in the third trimester due to accessibility and comfort, and a right-side tilt doesn’t relieve the vena cava compression as effectively as the left tilt. A supine position is to be avoided because it can worsen vena cava compression and reduce uteroplacental perfusion.