The standard of top-hip length in three months of pregnancy

The fetal top-to-butt diameter is the length from the head to the buttocks of the fetus when it is in the mother's womb. There is a folk saying that the gender of the baby can be determined by accurately measuring the fetal top-to-butt diameter. Therefore, many pregnant women go to the hospital for examination and are eager to get scientific data. Let’s discuss below how much the standard top-to-hip length is when you are three months pregnant.

The standard of top-to-hip length in three months of pregnancy:

In the early stages of pregnancy or within 12 weeks of pregnancy, the brachiocephalic diameter is equal to the number of weeks of pregnancy minus 6.5. At 12 weeks of pregnancy, the brachiocephalic diameter is approximately 5.5 cm, which is a general regularity. The brachiocephalic diameter at 11-13 weeks of pregnancy has the function of checking the pregnancy week. Since all test tube embryos grow and develop synchronously in the early pregnancy, the pregnancy week estimated by B-ultrasound is more accurate than the pregnancy week estimated based on the expected date of delivery. According to the estimated due date of pregnancy, the patient is 12 weeks pregnant, but the arm-head diameter is only 4.5 cm. After checking the gestational age, it is found that the patient is now 11 weeks pregnant, not 12 weeks, and the due date is relatively one week later.

Is there a difference between the standard crown-hip diameter of a fetus for men and women?

Generally speaking, there is no scientific evidence to determine the gender of a baby based on the crown-to-rump diameter of the fetus. From the baby's body, you can only see the baby's size, and it is actually not accurate to determine the baby's gender by this. However, if you go to the hospital for a B-ultrasound after four months of pregnancy, you can determine the gender of the baby. Professional doctors can already tell it, but this has been completely banned in our country and is considered an illegal act. Parents can just go with the flow regarding the baby's gender.

What is the specific effect of the fetal crown-buttock diameter?

When examining the fetus in early pregnancy with color Doppler ultrasound, the crown-rump diameter is often used to estimate the fetus' gestational age, which is a more accurate method of estimation. At the beginning of 6 weeks, the embryo is very small and the measurement is inaccurate. As the pregnancy weeks increase, the embryo grows and its shape curve becomes C-shaped, with the front end relatively large and easy to distinguish. Therefore, the following formula is used to calculate gestational age. The crown-to-rump diameter of the fetus refers to the distance from the top of the skull to the edge of the buttocks, and is usually accurately measured around 7-12 weeks of pregnancy.