Fetal head circumference reflects the development of the fetus and varies in size at different gestational weeks. It can be categorized into the middle and late stages of pregnancy.
1. Mid-pregnancy: the normal range of fetal head circumference in the 16th week of pregnancy is 10.3-13.6cm, the normal range of head circumference in the 18th week of pregnancy is 12.8-16.1cm, the normal range of head circumference in the 20th week of pregnancy is 15.2-18.6cm, the normal range of head circumference in the 22nd week of pregnancy is 17.6-21.1cm, the normal range of head circumference in the 24th week of pregnancy is 19.9-23.4cm, and the normal range of head circumference in the 26th week of pregnancy is 22-25.7cm. The normal range of head circumference in the 26th week of pregnancy is 22-25.7cm.
2. late pregnancy: 28 weeks gestation fetal head circumference normal range is 24-27.7cm. 30 weeks gestation fetal head circumference normal range is 25.8-29.6cm, 32 weeks gestation fetal head circumference normal range is 27.4-31.3cm, 34 weeks gestation fetal head circumference normal range is 28.8-32.7cm, 36 weeks gestation fetal head circumference normal range is 29.8-33.8cm, 38 weeks gestation fetal head circumference normal range is 29.8-33.8cm, 36 weeks gestation fetal head circumference normal range is 29.8-33.8cm, 36 weeks gestation fetal head circumference normal range is 29.8-33.8cm. The normal range of fetal head circumference at 38 weeks of pregnancy is 30.6-34.7cm.
Regular checkups are needed during pregnancy, and any abnormalities should be seen promptly.