Final answer:
A woman will usually feel the first fetal movements during the second trimester, approximately between weeks 16 and 20.
Step-by-step explanation:
A woman will typically feel the first fetal movements during the second trimester of pregnancy. Specifically, this occurs approximately between weeks 16 and 20, when the fetus grows and the limb movements become stronger. During the second trimester, many changes occur, including weight gain and a subsidence of nausea and vomiting, if present during the first trimester. The fetus becomes more active, and as it reaches about 30 cm (12 inches) in length, the pregnant person may begin to notice quickening, which are the initial movements felt. The placenta, having taken over many crucial functions, supports the pregnancy throughout this significant growth phase.