When is fetal movement usually felt?

Most women feel the beginnings of fetal movement before 20 weeks' gestation. In a first pregnancy, this can occur around 18 weeks' gestation, and in following pregnancies it can occur as early as 15-16 weeks' gestation. Early fetal movement is felt most commonly when the woman is sitting or lying quietly and concentrating on her body. It is usually described as a tickle or feathery feeling below the umbilical area. As the fetus grows in size, these feelings become stronger, regular, and easier to feel. The medical term for the point at which a woman feels the baby move is quickening. Babies should move at least 4 times an hour as they get larger, and some clinicians advise patients to count fetal movement to follow the baby's well-being.

Source: http://reference.medscape.com/