What is the biparietal diameter and femur length at 36 weeks?

What pregnant mothers are most concerned about is the development and growth of the baby in the belly. The 36th week of pregnancy is already the late stage of pregnancy. At this time, the baby has developed well and is ready to come into the world at any time. The biparietal diameter and femur length at 36 weeks depend on the individual differences of the baby. Generally, the difference is not big, but the differences are relatively large in the cases of multiple fetuses, mentally retarded babies, and malformed babies. The following is a detailed introduction to the developmental standards of a 36-week-old baby:

A 36-week-old fetus weighs about 2,800 grams and is about 46-50 centimeters long.

The biparietal diameter of the fetal head, also known as BPD, is a reference data. Doctors often use it to observe the child's development and determine whether there is cephalopelvic disproportion and a smooth delivery. During the delivery process, the maximum diameter of the fetus's head passing through the birth canal is the biparietal diameter, and the minimum diameter of the birth canal for the fetus to pass through is the transverse diameter of the pelvic outlet. Therefore, if the biparietal diameter is larger than the transverse diameter of the pelvic outlet, whether the child can be delivered naturally becomes a problem. The final choice depends on the pregnant woman's pelvis and the size of the baby at full term.

When the baby is full-term, the BPD should reach 9.3 cm or more. 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, the average weekly growth of about 0.2 cm is normal. The standard biparietal diameter of the fetus at 36 weeks is 8.81 ± 0.57.

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.

The biparietal diameter of the fetus is usually measured by ultrasound. As the fetus grows older, the skull continues to grow. When measuring the biparietal diameter, it should be measured from the inner edge of the skull on one side to the outer edge of the skull on the opposite side. This value is more accurate. If the examination is conducted in different hospitals, by different doctors, and on different machines, the value will be biased.

Fetal growth and development at 36 weeks of pregnancy: the average biparietal diameter is 8.81±0.57', the average abdominal circumference is 29.44±2.83', and the average femur length is 6.95±0.47. This week, the fetus's nails have grown longer, both kidneys have fully developed, and his (her) liver is able to process some waste. At this time, the mother's uterine wall and abdominal wall have become very thin, so more light will penetrate into the uterus, which will help the fetus gradually establish my daily activity cycle. The proportion of amniotic fluid in the uterus decreases, and the volume occupied by the fetus increases. The fetus is now 1,000 times the size of the original embryo. The mother's weight gain has also reached its peak, with an increase of approximately 11 to 13 kilograms. You will now need to have weekly prenatal checkups.

If you find that the fetus moves less, you should ask the doctor to teach you how to correctly monitor the fetal heart rate and movement. If the doctor finds that the fetus is a little small, he will recommend you to do a fetal heart monitoring to understand the condition of the fetus in the uterus, and will also recommend you to increase nutrition; if the fetus is already very large, the doctor may ask you to control your diet appropriately to avoid the fetus being too large and causing difficulties in your delivery. At this time, my mother's belly was quite heavy. Her belly was so big that her belly button was bulging out, making it quite difficult for her to move, sit or lie down. At this time, you must pay attention to safety when going up and down stairs and taking a bath to prevent slipping. At the same time, when doing housework, you must also pay attention to moving slowly and gently, not too vigorously, try not to bend over or squat, and never do any dangerous climbing movements. At this time, you should also learn about the signs of labor, understand what are uterine contractions, spotting, water breaking, and how to deal with them, etc., because you may go into labor at any time now.

The 36-week biparietal diameter and femur length standard is just a definition. Expectant mothers should not worry about the numerical values ​​appearing in the B-ultrasound. Modern medical technology is relatively developed, but there will also be some deviations. As long as the child has no obvious abnormalities, it is considered to be normal development. Expectant mothers must maintain an optimistic attitude at this time, ensure adequate nutritional intake, and prepare some baby products for the baby in advance, so as to be ready for the baby's arrival at any time.