Extraordinary swelling of the legs in late pregnancy is not a sign of impending labor. Whether labor is imminent or not needs to be judged by the expected date of delivery, whether there are regular contractions, premature rupture of membranes and other symptoms.
Swelling of the legs in late pregnancy may be caused by edema of the lower limbs because the enlarged uterus compresses the inferior vena cava, affecting its return to the right heart. It may also be caused by a combination of kidney or heart disease, and the degree of edema should not be used to judge whether labor is imminent.
Under normal circumstances, the doctor will estimate the expected date of labor based on the time of the mother’s last menstrual period. If the due date is approaching, or if there are regular contractions, or if there is a clear fluid, i.e. amniotic fluid, caused by premature rupture of the membranes, these are signs of impending labor, and it is advisable to go to the hospital immediately to wait for the delivery of the baby.