When does a fetus become conscious?

It is widely accepted that a fetus begins to feel pain around 20 weeks into pregnancy. By this time, the baby's tissues, muscles and nerves are developed.

However, studies using ultrasounds have shown that a fetus reacts to stimulation in the womb. For example, neurobiologist M. Fitzgerald reported in "Neurobiology of Fetal and Neonatal Pain" (1994) that at 7.5 weeks' gestation, a fetus responds to stimuli. Around 10.5 weeks, a fetus whose mouth region is touched will bend his or her head in response, and the palms of the hands become sensitive to stroking. The rest of the body and legs become sensitive at approximately 13.5 weeks.