Vertex presentation accounts for approximately what percentage of births?

• A. 95 percent
• B. 50 percent
• C. 20 percent
• D. 75 percent

Answer: (A)

Vertex presentation means the fetus is head-down in the birth canal, with the occiput (the back of the head) leading. It is by far the most common presenting position at birth. In pregnancies that reach labor, about 95% of births are in this head-down, head-first presentation. That makes 95% the best estimate for how often vertex presentation occurs. The other percentages—significantly lower or much higher—don’t match the typical distribution, since breech or other malpresentations account for only a small fraction of births.