Will the fetus enter the pelvis if it is in an abnormal position? Pregnant mothers must watch

Malposition of the fetus is a common phenomenon. Not all expectant mothers have encountered this situation and are very worried, fearing that the baby will not be able to enter the pelvis. Experts say that even if the fetus is in an abnormal position, it can still enter the pelvis, but you must have regular physical examinations during this period and seek medical attention immediately if you feel any discomfort.

1. What is malposition of the fetus

Fetal position, in layman's terms, refers to the position of the fetus in the uterus. The posture of the fetus in the womb before birth is very important, as it determines whether the pregnant woman will have a normal delivery or a difficult delivery. The fetus in the uterus is immersed in amniotic fluid. Because the fetal head is heavier than the fetal body, the fetus is mostly in a head-down, hip-up position.

Abnormal fetal position is one of the common factors causing dystocia. During delivery, occiput anterior position (normal fetal position) accounts for about 90%, while abnormal fetal position accounts for about 10%. Among them, abnormal position of the fetal head is the most common, including persistent occiput transverse position and persistent occiput posterior position due to obstruction of the fetal head rotation in the pelvic cavity; there are face presentation and frontal presentation with varying degrees of extension due to poor flexion of the fetal head; there are also high upright position and uneven anterior tilt position, etc., which together account for about 6% to 7%. Abnormal breech presentation accounts for about 3% to 4% of fetal delivery, while shoulder presentation is extremely rare. There is also a compound presentation. During the delivery process, the fetal head is connected in the occipital posterior position or the occipital transverse position. During the descent process, the occipital part of the fetal head can rotate forward 135° or 90° due to strong uterine contractions, turning into the occipital anterior position and causing natural delivery. If the occipital bone of the fetal head cannot be turned forward and remains at the back or side of the maternal pelvis until the late stage of delivery, causing difficulty in delivery, it is called persistent occipital posterior position. Since abnormal fetal position will bring varying degrees of difficulty and danger to delivery, early correction of fetal position is of great significance in preventing dystocia.

2. Can the fetus enter the pelvis if it is in an abnormal position?

Abnormal fetal position will cause the fetus to enter the pelvis. Engagement refers to the process in late pregnancy when the fetus, surrounded by amniotic fluid and fetal membranes, lies with its head down, buttocks up, and the whole body curled up, so that its head enters the pelvic cavity through the mother's pelvic entrance, thereby consolidating its body position. When the fetus enters the pelvis, many pregnant women often feel a tightness and pain in the abdomen. The presenting part can also enter the pelvis when the fetus is in an abnormal position. The first baby usually enters the pelvis four weeks before conception, and sometimes enters the pelvis two weeks before conception. After the fetus enters the pelvis, your belly will look different than before. Your chest will no longer touch your belly, and the shape of your belly will look a bit like a grapefruit. You will feel more relaxed than when your belly is at its largest! My stomach feels a bit hard. After the baby enters the pelvis, you will have more obvious uterine contractions, which feel like dysmenorrhea. The further down the baby goes, the more severe your menstrual cramps will be. Some people may also experience frequent urination. It is recommended that pregnant mothers look in the mirror to observe the shape of their belly every day. They can observe it in front of the mirror for a few minutes after taking a shower or getting up in the morning. Gradually, they will find that the shape of their belly will be a little different.

If the pregnant mother's fetal position is not correct, it is recommended to correct the posture: lie on a flat surface, bend your knees and lift your hips. You can use a pillow or something like that to place under your back or buttocks. Lift the mattress or iron plate at an angle of 12-18 degrees to the ground to form an inclined plane, then bend your knees, kneel down and lift your hips, with your head facing the side that is inclined to the ground. If the breech presentation cannot be corrected, a caesarean section is recommended.