What percentage of people cant have babies?

This is just the percentage for the United States. Infertility affects about 7.1 percent or 2.8 million couples that are of the married people in the United States, infertility's most common causes include egg quality/production, blocked tubes, and the male-factor, infertility also affects about 7.3 million people of childbearing age in the United States and about 10-15 percent of the reproductive-age population, according to the Centers for Disease Control.

For women within the USA about 7% of married women are infertile by age 30, about 11% by age 35, about 33% by age 40 and about 87% at age 45.