Is the femur length of 71 mm at 37 weeks of pregnancy long?

Generally, a femur length of 71 mm at 37 weeks of gestation is not considered long for the fetus and falls within the normal range.

Around 37 weeks of pregnancy, women can undergo a four-dimensional color ultrasound examination to assess whether the fetal organs are developing normally. Femur length is one of the important indicators used to evaluate fetal growth and development. The normal range for fetal femur length at 37 weeks is 6.20–7.60 cm, with an average of 7.2 cm. Therefore, a femur length of 71 mm at this stage is not particularly long but remains well within the normal range. The fetus still has significant room for further development in the later stages of pregnancy.

Fetal femur length refers to the length of the fetal thigh bone. During pregnancy, the fetal femur should generally remain within a normal range—either too short or too long may indicate potential issues. Fetal femur growth is primarily influenced by protein and calcium intake. Pregnant women are advised to maintain a balanced diet, consume more vegetables and fruits, increase intake of high-quality proteins such as eggs and milk, and get adequate sun exposure to promote calcium absorption. Regular prenatal check-ups are essential during pregnancy to monitor fetal development closely and allow timely interventions if any abnormalities are detected.