The Arrest of Descent - Types and Risk Factors

Introduction

Although childbirth is typically a safe and natural process, it can be complex and certain complications may arise. Dysfunctional labor is a term used to describe abnormal or difficult childbirth or delivery. This can occur when the labor slows down, which is known as protraction, or when the labor comes to a complete stop, which is referred to as an arrest of descent.

The stages of labor begin before the delivery. In the first stage, the contractions start till the mother is fully dilated. After that, the cervix becomes ready for the child's birth. Finally, the second stage begins with complete dilation of the cervix and ends with the baby's birth. Many pregnant women go through these stages without facing any issues. But some women may experience abnormal labor during any of these stages.

What Is the Arrest of Descent?

The arrest of descent is when the head of the fetus is in the same place in the birth canal during the first and second examinations, which the doctor has performed an hour previously apart. It means the fetus's body has not moved the birth canal downwards within the last hour. The arrest of descent is diagnosed in the second stage when the cervix is completely dilated. The abnormal delivery can be corrected to vaginal delivery by administering oxytocin to promote the labor. This type of medication helps to stimulate uterine contraction by enhancing labor. The oxytocin can be given through a vein using a medication pump to start and maintain the regular contractions of the uterus. These contractions help the mother dilate the cervix and also help push the baby out of the uterus. The dose of oxytocin varies from one woman to another.

What Are Different Types of Abnormal Labor?

The following types of abnormal labor can happen in any of the stages of labor:

• Uterine Hypocontractility - It is most common in women going into labor for the first time. The labor may begin well, but it can stop later if the uterus cannot contract sufficiently. This type of labor is called uterine hypercontractility or uterine inertia. It can be because of the medications that lessen the frequency or intensity of the contractions.

• Macrosomia - This condition occurs when the fetus is much larger than average and weighs more than eight pounds and 13 ounces. Around 9 % of babies born have macrosomia. This condition can cause injury and problems during childbirth. In addition, there is an increased risk of health problems for the child after birth. Also, the mother and the baby are at high risk if the baby weighs more than 9 pounds and 15 ounces.

• Shoulder Dystocia - Shoulder dystocia is a condition where the baby's head is delivered through the vagina of the mother, but the shoulders are stuck inside the mother's body. This cannot be discovered until the labor has begun, it can only be found at the time of labor, so there is no way to prevent or predict it. This condition is risky for both the mother and the baby. There can be injuries, which include excessive tearing or bleeding of the vagina, cervix, and rectum. In addition, the baby can experience a lack of oxygen supply to the brain and brain damage. In many cases, the babies are delivered safely as doctors can ease the baby out by turning the baby's shoulder and applying pressure to the mother's lower belly.

• Uterine Rupture - The uterine rupture is tearing in the wall of the uterus, especially at the site of the previous injection. This condition is rare and is seen in women who have had uterine surgery or women who have a history of cesarean delivery. However, uterine rupture is seen when an emergency cesarean delivery is necessary to prevent severe problems in the mother and the child. The serious problems include heavy bleeding in the mother and brain damage in the child. So in some cases, a hysterectomy is necessary to stop the mother's bleeding.

• Cephalopelvic Disproportion (CPD) - CPD is very rare. If the labor is slow even after receiving oxytocin, the baby's head might be too large to fit through the pelvis, and this condition is called cephalopelvic disproportion. Women who experience CPD can give birth by cesarean delivery.

• Precipitous Labor - The three labor stages last about six to 18 hours. Precipitous labor is also called rapid labor. With this labor, the stages progress more quickly, lasting about three to five hours. This may occur for several reasons. When the woman has a history of precipitous labor, the baby is smaller than average, and uterus contractions are powerful.

• Umbilical Cord Prolapse - This condition occurs when the umbilical cord slips out of the cervix in the vagina, ahead of the baby. This can lead to compression of the umbilical cord or increased pressure on the umbilical cord.

• Retained Placenta - The placenta is formed in the uterus and attaches to the uterine wall during pregnancy. It helps in providing nutrients and helps to remove the waste created by the baby's blood. The retained placenta develops when the placenta is left behind in the cervix or remains attached to the uterine wall. If the condition is untreated, it causes complications.

• Postpartum Hemorrhage - Postpartum hemorrhage occurs when there is an excessive bleeding after childbirth, especially after the delivery of the placenta. The women will lose 500 milliliters of blood after birth, while the postpartum hemorrhage will cause them to lose double the blood. This condition occurs after the cesarean delivery if an organ is cut or the blood vessels are not appropriately stitched. This condition can be extremely dangerous for the mother, as too much blood loss can cause a steep drop in blood pressure, leading to severe shock if not treated. The women experiencing postpartum hemorrhage are given blood transfusions to replace blood loss.

What Are the Risk Factors For the Arrest of Descent?

Major risk factors for the arrest of descent are:

• Fetal macrosomia.

• Epidural analgesia.

• Hydramnios.

• Hypersensitive disorders.

• Gestational diabetes mellitus.

Conclusion

Labor is a unique and natural process. It is different for every woman. It can be a matter of hours for some women, but it could test their emotional and physical stamina. The arrest of descent is when the baby stops descending through the birth canal despite adequate contractions and pushing efforts. It can be due to fetal malposition, a large baby, a narrow pelvis, or weak contractions. Interventions like changing positions, forceps, vacuum extraction, medication, or cesarean section may be necessary. Close monitoring and early identification of potential issues are crucial.