5-month-old fetus biparietal diameter standard

During prenatal checkups, doctors will generally perform a biparietal diameter test on the mother. The biparietal diameter test can effectively check the degree of development of the fetus's head and pelvis, and this test can also allow pregnant women to decide whether to have a natural birth. The growth of the fetus in each period is different, so the biparietal diameter value in each period is also different. However, when a pregnant woman is 5 months pregnant, what is the normal standard for the biparietal diameter of the fetus?

Biparietal diameter and femoral length of the fetus at five months of pregnancy

1. A 13-week-old fetus is about 6 cm long from the top of the head to the buttocks, the biparietal diameter (the largest transverse diameter of the skull) is about 2.52 cm, and the femur is about 1.17 cm long (i.e. the length of the thigh). The fetal biparietal diameter refers to the length of the widest part between the left and right sides of the fetal head, also known as the "great transverse diameter of the head." Also known as BPD, doctors often use it to observe the child's development and determine whether there is cephalopelvic disproportion and a smooth delivery. Experts remind: It is not scientific to use the biparietal diameter to determine whether the fetus is male or female. However, the biparietal diameter can be used to calculate the fetal weight, and the formula is: fetal weight = biparietal diameter * 900-5200 (g).

2. It should reach 9.3 cm or above at full term. According to general rules, after 5 months of pregnancy, the BPD is basically consistent with the month of pregnancy, that is, at 28 weeks of pregnancy (7 months) the BPD is about 7.0 cm, at 32 weeks of pregnancy (8 months) it is about 8.0 cm, and so on. After 8 months of pregnancy, an average weekly growth of about 0.2 cm is normal. When the due date cannot be determined by CRL in the early stage, BPD is often used to predict it; after the middle stage, this data is often also needed to be measured when estimating the fetal weight. Femoral length (FL) is an indicator commonly used by doctors to observe fetal development when performing pregnancy examinations on pregnant women using B-ultrasound (or color ultrasound).

3. The femur and humerus are both typical long tubular bones in the human body, and can be divided into two ends. The femur is the largest long bone in the human body and refers to the thigh bone; the humerus is located in the upper arm and is also called the upper arm bone. So as the names suggest, femur length refers to the length of the thigh bone, and humerus length refers to the length of the upper arm bone.

The above is the editor's answer to the biparietal diameter and femur length of the fetus at five months of pregnancy. It turns out that under normal circumstances, the fetus is about 2.5 cm, but there may be a certain deviation because everyone is different. The larger biparietal diameter of the fetus is a manifestation of the larger fetus, which is directly related to the good nutrition and low activity of the expectant mother, so the editor recommends that you can exercise appropriately under the premise of safety.