Does the head position mean it is in the pelvis?

As the fetus grows slowly over time during pregnancy, some changes will slowly occur in the abdomen. The presence of a head position on B-ultrasound is a common condition in late pregnancy. The head position of the fetus is not a sign of entering the pelvis, but just a change in the position of the fetus, a posture for delivery. After the fetus enters the pelvis, it is easy for the amniotic fluid to rupture, or there may be frequent urination, and abdominal pain.

Does the head position mean the fetus is about to enter the pelvis?

What do head presentation and pelvic engagement mean? The baby grows in the belly and floats in the amniotic fluid. Depending on the different body positions, it can be divided into head presentation and breech presentation. Head presentation means the head is facing down. If it is a normal birth, the head can come out first. Basically, the baby's biparietal diameter is the widest part of the body. As long as the head can come out, the lower part can generally come out as well. Another position is the breech position, which means the buttocks are facing downwards. This position does not allow for a normal birth because if the baby's head cannot come out first, it can easily cause hypoxia.

However, the baby's head position does not mean that it has entered the pelvis. Generally speaking, the baby may be in the head position when checked at around six months, but to enter the pelvis, it takes at least until the eighth or ninth month of pregnancy. Entering the pelvis means that the baby's head enters the pelvis, which is divided into shallow entry and complete entry. If it is completely entered, the baby's position is fixed and will not change. At this time, the stomach will feel like it is falling, and the urination will be more frequent.

So the baby's head position and the baby's engagement in the pelvis are two completely different concepts. The baby's head position means that the baby's head is facing downwards, and this position allows for normal delivery. The baby's engagement in the pelvis means that the baby's head has entered the pelvis, and this can be determined by letting the doctor touch it during the prenatal check-up. However, the engagement in the pelvis is divided into two types: shallow engagement in the pelvis and complete engagement in the pelvis. If it is shallow engagement in the pelvis, the amniotic fluid may float out again after too much fluid.

Is the fetal head position in the pelvis?

The fetal head is not in the pelvis. Fetal head position refers to the situation in which the fetus's head has turned to a downward position in the late pregnancy. The fetal head position is to prepare for normal delivery, and a fetus in head position is conducive to normal delivery. Corresponding to the fetal head position are fetal breech position and transverse position, which all mean that the fetal position is incorrect and the fetal head is not kept downward, which is not conducive to normal delivery. The fetus is in the pelvis when the top of the fetus's neck reaches below the entrance of the mother's pelvic cavity and the fetal head and pelvis are symmetrical, indicating that vaginal delivery is possible and the first step of the delivery process has been completed, laying a good foundation for a smooth delivery.

Malposition of the fetus is more common in pregnant women and multiparous women with loose abdominal wall. The causes of malposition of the fetus include uterine hypoplasia, uterine malformation, narrow pelvis, pelvic tumors, fetal malformation, polyhydramnios and other factors.

1. Excessive amniotic fluid in pregnant women causes the fetus to move too much in the uterine cavity. The fetus can move freely in a wider space. Excessive movement will affect the fetal position and make it loose.

2. Narrow pelvis, placenta previa, giant fetus, etc., make the fetal delivery difficult. The fetal head cannot be positioned well, which may cause squeezing and malposition of the fetus.

3. The mother's abdominal wall is loose. The loose abdominal wall will cause the abdominal muscles to lose support for the uterus, become inelastic, and become loose, thus causing malposition of the fetus;

4. Fetal malformations, uterine malformations, etc. cause changes in the space of the uterine cavity, which in turn changes the range of movement of the fetus in the uterine cavity, thus causing malposition of the fetus.