Fetal movements are perceived by the women as a sensation of discrete kick, flutter, swish or roll. Movements are first perceived by the mother between 18 and 20 weeks of gestation. Women in their first pregnancy may perceive movement much later than 20 weeks of pregnancy, but women who have been pregnant before may perceive fetal movements as early as 16 weeks pregnancy in the subsequent pregnancies.
Fetal movements provide an indication of the integrity of the central nervous and musculoskeletal systems. The normal fetus is active and capable of physical movement, and goes through periods of both rest and sleep. The number of spontaneous movements tends to increase until the 32nd week of pregnancy. From this stage of gestation, the frequency of fetal movements plateaus until the onset of labor; however, the type of fetal movement may change as pregnancy advances in the third trimester. Fetal movements are usually absent during fetal ‘sleep’ cycles, which occur regularly throughout the day and night and usually last for 20–40 minutes. These sleep cycles rarely exceed 90 minutes in the normal, healthy fetus. There is some evidence that women perceive most fetal movements when lying down, fewer when sitting and fewest while standing. Sedating drugs, alcohol, cigarette smoking is associated with a decrease in fetal activity.
Women are advised to be aware of their baby’s individual pattern of movements. If at any time they feel that the movements (commonly called as the kick count) are reduced or absent then they are advised to lie on their left side and focus on fetal movements for 2 hours. If they do not feel 10 or more discrete movements in 2 hours, they should contact their doctor.