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10 Reasons You Might Not Know You're Pregnant (Until You're in Labor)

An Inactive Baby

Baby kicks are quite common for most pregnant women, but not for all.

Whether the baby rests in such a way that makes its movements hard to detect or it's simply less active than others babies, movement in the womb -- or lack thereof -- can shape a woman's perception of her pregnancy.

Women who didn't know they were pregnant sometimes put the pieces together in retrospect, noting instances when they confused their babies' movements with indigestion or an upset stomach.

In addition, the position of the baby matters as well. Sometimes, the baby may rest in a breeching position with its feet fixed toward the bottom of the womb. Since natural birth favors the baby exiting the mother's womb headfirst, doctors often try to reposition a breeched baby during labor.

Some women claim they became pregnant even after using contraceptives. Find out more next.