What is Placental Abruption?
Placental abruption is a condition where the placenta, which provides nutrients and oxygen to the baby, separates too early from the uterus wall before the second stage of labor is complete. This condition can cause bleeding during the later stages of pregnancy. Though it does not happen frequently, placental abruption is a serious pregnancy complication that can risk the health of both the mother and the baby. This condition is also referred to as abruptio placentae.
What Causes Placental Abruption?
Placental abruption, which is when the placenta detaches from the wall of the uterus during pregnancy, happens for reasons that are still unclear. But, it’s associated with several risk factors that are usually grouped into three categories: health history, current pregnancy, and sudden trauma.
Factors from the mother’s health history that can raise the risk of placental abruption include smoking, using cocaine during pregnancy, being older than 35 years, high blood pressure, and having had placental abruption in a previous pregnancy. Events or conditions linked to the current pregnancy that increase the risk include multiple pregnancies (having more than one baby at the same time), having excess amniotic fluid (a condition known as polyhydramnios), high blood pressure during pregnancy (preeclampsia), sudden release of amniotic fluid (uterine decompression), and having a short umbilical cord.
Additionally, physical injury to the abdomen from car accidents, falls, or physical aggression can also potentially lead to placental abruption.
Placental abruption usually happens when the blood vessels that connect the uterus and the part of the placenta facing the mother get damaged. These blood vessels are needed to deliver oxygen and nutrients to the baby. The damage can happen because of high blood pressure, drug use, or anything that causes the uterus to stretch a lot.
The uterus is a muscle that can stretch whereas the placenta cannot stretch as much. So, if the uterus suddenly stretches out, the placenta stays in place and the blood vessels connecting it to the uterus can tear away.
Risk Factors and Frequency for Placental Abruption
Placental abruption is a fairly uncommon condition, but it needs immediate medical attention. It generally happens before the 37th week of pregnancy and constitutes a significant cause of health problems in mothers and death in newborns. It can lead to several serious health risks for the mother, such as:
- Bleeding which may require blood transfusions or a hysterectomy (removal of the uterus)
- Bleeding disorders, specifically a condition called disseminated intravascular coagulopathy
- Kidney failure
- Conditions like Sheehan syndrome or postpartum pituitary gland death.
Deaths in mothers due to placental abruption are rare thanks to blood replacement therapies, but the chances are still higher than the overall rate of death in mothers. Babies could have problems like being born too early (preterm birth) and being small (low birth weight), inability to breathe properly at birth (perinatal asphyxia), stillbirth, and death. Interestingly, even with improved pregnancy care and monitoring, the number of placental abruptions has been growing in many countries. This hints at the fact that it’s caused by many different things and is still not well understood.
Signs and Symptoms of Placental Abruption
Placental abruption is a cause of vaginal bleeding in the latter part of pregnancy. To differentiate this from other causes of vaginal bleeding, a careful medical history and physical examination are necessary. Because we can only confirm placental abruption after delivery by examining the placenta, understanding the patient’s initial signs and symptoms is crucial to treatment and care. Placental abruption is critical and could potentially be life-threatening, so precise assessment is necessary to design the right treatment plan and prevent undesirable outcomes.
The assessment should start by reviewing the history of the pregnancy, focusing on the location of the placenta based on previous ultrasound scans and whether there’s a history of placental abruption in past pregnancies. The woman’s activities, particularly if she smokes or uses drugs like cocaine, should also be discussed. Any suspected trauma, particularly around the abdominal area, should also be talked about in a supportive and sensitive manner, as the woman could be hesitant to disclose injuries due to domestic abuse.
A physical inspection is vital for recognizing the symptoms of placental abruption. This includes feeling the uterus to check for tenderness and changes in firmness and monitoring the frequency and duration of potential contractions. The vagina should be inspected for bleeding, but an internal check should be postponed until an ultrasound can confirm the placenta’s location and rule out other conditions like placenta previa. If there’s bleeding, the amount and quality of the blood and the presence of clots should be noted. Importantly, lack of vaginal bleeding does not rule out placental abruption.
Checking vital signs for rapid heartbeat or low blood pressure, which might suggest hidden bleeding, is crucial. A blood sample could be taken for a complete blood count, fibrinogen levels, clotting profile, and blood type, and RH testing.
Lastly, evaluation of the baby’s condition is also part of the examination. This starts with listening to the fetal heartbeat and asking about the baby’s activity, especially any changes in movement. Continuous electronic fetal monitoring is also done to spot any slow heartbeat, decreased movement, and delayed decelerations.
Testing for Placental Abruption
While there are no specific tests or procedures that can definitely diagnosis placental abruption, some tests may be done to rule out other conditions and to establish a starting point for other data.
An ultrasound is helpful in finding where the placenta is positioned and to rule out a condition called placenta previa. But, ultrasounds aren’t very good at showing placental abruption because the bleeding may look similar to the nearby placental tissue. This makes it hard to see and differentiate any internal bleeding that may be happening with placental abruption.
A biophysical profile might be used for patients with a slight placental abruption who are being handled delicately. A score of 6 or less can suggest that the baby’s health is at risk.
Blood tests, including a complete blood count (CBC), clotting tests (checking levels of a protein called fibrinogen and testing prothrombin time/partial thromboplastin time or PT/a-PTT), and a test that checks kidney function (BUN), are used to establish baseline measurements, to notice any changes in the patient’s condition. A blood type and Rh test can be done if a blood transfusion could be needed.
A Kleihauer-Betke test, which checks for baby’s blood cells in the mom’s circulation, may be ordered. This test doesn’t diagnose the presence of placental abruption. Instead, it measures the amount of baby’s blood in the mom’s circulation. This information is particularly important in women who are Rh-negative because mixing of baby’s blood in the mom’s circulation might lead to a condition called isoimmunization. Therefore, if there is significant mixing of baby’s and mom’s blood, the Kleihauer-Betke test results can help to work out the needed dose of a medicine called Rh (D) immune globulin to prevent isoimmunization.
Treatment Options for Placental Abruption
Placental abruption is a pregnancy complication that typically occurs suddenly and requires immediate caution and treatment. It’s crucial for a patient with suspected placental abruption to receive immediate medical attention and be taken to a hospital equipped with both an obstetrical unit and a neonatal intensive care unit.
Upon arriving at the hospital, women generally receive an IV drip for hydration, supplemental oxygen for better breathing, and continuous monitoring for both the mother and the baby’s wellbeing. The specifics of the following treatment will depend on the details collected during the health assessment, the stage of the pregnancy, and the level of discomfort or complications faced by the mother and/or the baby.
If diagnosed as a mild case (class 1) of placental abruption, with no signs of maternal or baby distress, and the pregnancy is less than 37 weeks, women may be monitored rather than receiving aggressive treatment. These patients are usually admitted to the obstetrical unit for close observation. Healthcare practitioners ensure IV access and conduct blood work for further examination. The mother and baby will continue to be closely monitored until there is a change in condition or the pregnancy progresses to full term.
In contrast, for more serious cases (class 2 or class 3), if the baby is alive and can survive outside the womb, delivery is vital. The severe contractions might lead to a fast vaginal birth, which is less risky for the mother due to the potential for blood clotting disorders. However, if there are signs of distress in the baby, an emergency c-section may be needed to ensure baby’s safety. During this surgical process, careful fluid management and maintaining blood volume are important to prevent complications. After the surgery, the patient must be observed for excessive bleeding and changes in the blood clotting function. Also, a team specializing in newborn care must be present in the delivery room to take immediate care of the baby.
What else can Placental Abruption be?
Bleeding in the later stages of pregnancy is usually caused by either two conditions: placental abruption or placenta previa. It’s vital to tell these two conditions apart so the pregnant woman can receive the right care. Both of these conditions present themselves differently when a doctor carries out a pregnancy check-up.
- The onset of symptoms is sudden and intense for placental abruption, but slower and more subtle for placenta previa.
- With placental abruption, the bleeding might be visible or hidden, whereas with placenta previa, the bleeding is visible and external.
- For placental abruption, there is a higher degree of anemia or shock than the visible blood loss suggests, but for placenta previa, it matches the blood loss.
- Pain is intense and sudden in cases of placental abruption, whereas placenta previa does not cause pain.
- The uterus feels firm and hard in placental abruption, but remains soft and relaxed in placenta previa.
What to expect with Placental Abruption
The outlook for mother and baby largely depends on how quickly they get to the hospital. If the mother continues to bleed, both her life and the baby’s life are at risk. It’s less dangerous when only part of the placenta separates compared to when it fully separates. However, without an emergency cesarean section (a surgical operation to deliver the baby), the baby might not survive in both situations.
This condition causes between 5% to 8% of maternal deaths today, making it significant. It’s important to get medical help right away to improve their chances.
Possible Complications When Diagnosed with Placental Abruption
Common issues related to severe hemorrhage include the loss of the baby (fetal demise), death of the mother (maternal death), and the birth of a preterm baby. There may also be complications related to blood clotting (coagulopathy), transfusion-related problems, a surgical procedure to remove the uterus (hysterectomy), and the need for future births to be delivered by cesarean section. There’s also the chance of recurrence, which has been seen in 4% to 12% of cases. Lastly, women with placental abruption are reported to have an increased risk of heart-related problems.
- Severe bleeding
- Loss of the baby
- Death of the mother
- Birth of a preterm infant
- Blood clotting complications
- Problems related to transfusion
- Surgical removal of the uterus
- Necessity for future births to be by cesarean section
- Possibility of the problem happening again (4% to 12% of cases)
- Increased risk of heart-related problems in women with placental abruption
