Evaluation of pregnancy rate in crescent-shaped labor by perineal ultrasound

The article was professionally consulted by Doctor Nguyen Anh Tu - Diagnostic Imaging - Department of Diagnostic Imaging - Vinmec Hai Phong International General Hospital.

In obstetrics, pregnancy assessment is considered as one of the extremely important steps to prepare well for the delivery process of pregnant women. The status of ectopic pregnancy is determined when the diameter of the fetal position passes through the diagonal diameter of the upper waist of the pregnant woman, in which the diagonal diameter is the diameter from the sacroiliac joint on one side to the iliac crest spine on the other side. can be the right diagonal diameter or the left diagonal diameter. In clinical practice, before the fetal position can be passed through the diameter, some movements must be performed so that the fetal position can reduce the diameter of the fetal position to the maximum extent, which is beneficial to the health of the fetus. Pregnancy is then called correction or imaging. The fetal position can fall symmetrically or asymmetrically depending on each patient's case.

To evaluate the clinical pregnancy, it is necessary to examine the presence of the fetal position at the upper landmark of the mother's pelvis, that is, the relationship between the fetal head and the mother's hip spine. However, because these physical symptoms are examined subjectively and can vary from physician to clinician for the same patient, there is a large amount of variation in the diagnostic evaluation of the patient's symptoms. pregnancy, which makes this clinical examination unbiased and cannot be sure to confirm the pregnancy, not to mention the cases where it is difficult to assess the pregnancy through clinical examination such as: serous tumor or stack of bones, molded. In particular, in cases of fetal growth retardation, the assessment of pregnancy is even more important, so that the fetus can be brought out as soon as possible without affecting the life of both mother and fetus. Therefore, perineal ultrasound is considered a means of accurate diagnosis or assessment of pregnancy and helps to limit errors in clinical assessment.

The perineal ultrasound allows to investigate a number of important factors to help assess the pregnancy as follows:
Distance between the fetal head and the perineum: To assess the descent of the fetus in the uterine cavity, as soon as Amniotic fluid ruptures prematurely to the stage of delivery, and this factor is extremely important if the obstetrician has an indication for cesarean section. The distance between the fetal head and the perineum is measured as the smallest distance from the skin of the perineum to the outer border of the fetal skull, the shorter this distance, the faster the delivery time and the possibility of obstetric pain. is reduced. The distance between the fetal head and the joint: Calculated from the lowest border of the maternal pubic bone to the closest part of the skull to that position along the perpendicular axis of the maternal pubic bone. This distance is related to a number of other factors in ultrasound such as the angle of progression as well as the clinical examination of the mother's vagina to assess the pregnancy rate.

Fetal direction: The direction of fetal head along the axis of the mother's pubic bone, assessed by observing fetal head movement on ultrasound and the curve of the woman's pelvis. If the direction of birth is assessed as horizontal, downward, then giving birth with the help of an instrument will be very difficult and the success rate of delivery is very low. Angle of progression: The angle formed by the midline of the humerus and the tangent line of the pubic crest to the fetal skull. In order to be able to measure the progressive angle, during the ultrasound process, it is necessary to perform a lot of operations such as covering the transducer with clean rubber gloves with specialized ultrasound gel, inserting the probe into the large lips of the pregnant woman. and observe the ultrasound image showing the longitudinal axis of the pubic bone, then move the transducer upward to continue observing. At this time, the baseline is taken as the midline along the longitudinal axis of the maternal pubic bone and the tangent line to the fetal skull border below the pubic bone to measure the progression angle. The angle of progression is considered an important factor in ultrasound to evaluate the pregnancy rate

One of the common cases in clinical practice is cephalic delivery. After performing a perineal ultrasound to assess the fetal position and determine the fetal position, the cephalic delivery includes a number of steps. The basics are as follows:
The most important part is to support the head and shoulders of the fetus, the other parts are relatively easier. The midwife must intervene at the prescribed time. If the fetus falls, goes down or rotates, there is no need to intervene, except for difficult births, this time requires outside intervention. The natural birth process takes place in the following order: normalize the morph, fall, descend and rotate inward, complete internal rotation. These natural birth stages are not allowed any outside intervention.

Next, the midwife needs to intervene after the natural birth process has taken place to help the fetus bow well, including the first turn, second phase external rotation. Some conditions to be able to recognize and initiate the intervention in the birth process are the complete occipital rotation, the position ready for the delivery stage by the expression of perineal or vulva bulging towards the ceiling. at home, the baby's lips are separated on both sides. An episiotomy can be performed if necessary, but this is not a routine procedure.

Perineal transvaginal ultrasound examines a number of important factors for the purpose of assessing pregnancy, is a very useful technique in preparing for the most smooth delivery, minimizing the risks of pregnancy. unwanted complications in childbirth.
Vinmec International General Hospital offers a Package Maternity Care Program for pregnant women right from the first months of pregnancy with a full range of antenatal care visits, periodical 3D and 4D ultrasounds and routine tests to ensure that the mother is healthy and the fetus is developing comprehensively. Pregnant women will no longer be alone when entering labor because having a loved one to help them during childbirth always brings peace of mind and happiness.