Depending on the individual and the condition of the fetus, the femur length will still grow at 39 weeks of pregnancy in general. The standard femur length of a fetus at 39 weeks of pregnancy is between 6.81 cm and 7.87 cm, but if the fetus’s physiological condition as well as the femur is within the normal range, the femur length will continue to grow in the second trimester of pregnancy, but it will grow very slowly. At 39 weeks of pregnancy, the fetus is still growing, with a length of about 50 centimeters and a weight of about 2,900 grams to 3,400 grams. It is fully equipped to live in the outside world. At this time, pregnant women should pay more attention to rest, maintain a happy mood, adequate sleep, strengthen nutrition, appropriate exercise will help smooth labor.