What is the difference between fetal movements and fetal hiccups? Fetal movements and hiccups are common phenomena experienced by pregnant women. Although they seem similar, there are actually big differences between the two. Their differences will be introduced in detail in four aspects below. 1. Definition of fetal movement and fetal hiccups Fetal movement refers to the movement of the fetus in the womb. Usually pregnant women will start to feel it around 20 weeks of pregnancy.