The placenta is a remarkable organ that develops during pregnancy. It attaches to the wall of the uterus and connects to the baby via the umbilical cord. The placenta provides oxygen and nutrients to the growing baby and removes waste products from the baby’s blood. After the baby is born, the placenta is delivered as well. This is called the afterbirth. Typically, the placenta detaches from the uterine wall shortly after birth and is expelled from the uterus. However, in rare cases, all or parts of the placenta may fail to detach after delivery. This is known as retained placenta. If the placenta is not removed after birth, it can lead to potentially serious complications.
In this article, we will discuss what happens when the placenta is not expelled after childbirth. We will cover:
- Causes of retained placenta
- Risks and complications
- Diagnosis
- Treatment options
- Prevention
- Outlook if placenta is not removed
Understanding the implications of retaining the placenta is important for proper postpartum care.
Causes of Retained Placenta
There are several reasons why the placenta may fail to detach from the uterine wall after delivery:
- Uterine atony: This is the most common cause. After birth, the uterus should contract to help detach and expel the placenta. If the uterus fails to contract adequately, the placenta cannot detach normally.
- Placenta accreta: This is an abnormal adherence of the placenta to the uterine wall. The placenta grows too deeply into the uterus, which can prevent normal shedding after birth.
- Trauma: Damage to the uterus or placenta during labor and delivery can disrupt the separation of the placenta.
- Uterine rupture: A rare tearing of the uterine wall may damage the placenta and prevent detachment.
- Full bladder: A distended bladder can prevent the uterus from properly contracting after birth.
- Blood clotting disorders: Certain clotting or bleeding disorders may interfere with placental separation.
Identifying the underlying cause of retained placenta can guide proper treatment.
Risks and Complications
If the placenta is not expelled after delivery, it can lead to the following risks and complications:
- Hemorrhage: Retained placenta leaves exposed blood vessels that were connected to the placenta, which can lead to severe, uncontrolled bleeding. This postpartum hemorrhage is a leading cause of maternal death worldwide.
- Infection: Retained tissue increases the risk of developing an infection in the uterus called endometritis.
- Blood clots: The open blood vessels formerly connected to the placenta increase the chances of developing dangerous blood clots in the legs and lungs called thromboembolism.
- Anemia: Severe blood loss from an undelivered placenta can cause anemia, a low red blood cell count.
- Need for further surgery: Surgery may be required to remove a placenta that does not detach and deliver spontaneously.
- Subinvolution of the uterus: The uterus cannot return to its normal non-pregnant state when placental tissue remains attached.
Prompt diagnosis and treatment are crucial to prevent potentially life-threatening complications and long-term problems.
Diagnosis
If the placenta has not delivered within 30 minutes after childbirth, there is likely a problem with placental detachment. Diagnosis of retained placenta may involve:
- Physical exam to feel if the uterus is enlarged, indicating retained placental tissue.
- Ultrasound to identify placental tissue still attached to the uterus.
- Manual exploration of the uterus to try to locate and detach placental pieces.
- Lab tests to check blood count and levels of pregnancy hormones.
The amount of bleeding and the mother’s vital signs will also be monitored closely.
Treatment
If the placenta fails to deliver spontaneously, there are several options for removal:
- Uterine massage: Rubbing the abdomen may stimulate uterine contractions to expel the placenta.
- Medications: Oxytocin and prostaglandins promote uterine contractions to detach the placenta.
- Manual removal in the delivery room: A doctor inserts a hand in the uterus and gently pulls out pieces of the placenta.
- Curettage: A surgical scraping of the uterine lining to remove any residual placental tissue.
- Hysterectomy: Surgical removal of the uterus may be done in cases of severe hemorrhage or placenta accreta.
The specific treatment will depend on the clinical situation. IV fluids and blood transfusions are often needed to stabilize the mother.
Prevention
While retained placenta sometimes cannot be prevented, the following may reduce risk:
- Allowing the placenta to deliver spontaneously without pulling on the umbilical cord.
- Avoiding trauma to the uterine wall during delivery.
- Prompt treatment of any postpartum hemorrhage.
- Active management of the third stage of labor with oxytocin soon after birth.
- Identifying and managing placenta accreta during pregnancy.
Careful placental examination after birth can also reveal if there are missing pieces needing treatment.
Outlook If Placenta Is Not Removed
If retained placenta is left untreated, the consequences can be grave. The ongoing blood loss leads to hemorrhagic shock, requiring aggressive resuscitation and transfusion. Sepsis may develop from uterine infection. Extended hospitalization is often required in the intensive care unit. Up to 6% of women with retained placenta may die without proper treatment.
For survivors, long-term complications include:
- Chronic anemia
- Sheehan’s syndrome – pituitary gland damage
- Secondary infertility
- Need for hysterectomy
Rarely, untreated retained placenta can result in an abnormal passage forming between the uterus and another organ like the bladder or colon called a uterovesical fistula. This requires surgery to repair.
So early diagnosis and management are vital to prevent the potential life-threatening and permanent consequences of retaining placental tissue after childbirth.
Conclusion
The placenta is a remarkable organ formed during pregnancy that sustains the developing baby. Normally it detaches and is expelled shortly after birth. Retained placenta occurs when all or part of the placenta fails to detach from the uterine wall. This can lead to hemorrhage, infection, clotting issues, anemia and even death without proper treatment. Causes include uterine atony, trauma, and abnormal placental implantation. Diagnosis involves ultrasound, examination and monitoring bleeding and vital signs. Treatments range from medications to surgery. Complications of retained placenta can be severe, including hysterectomy, pituitary damage, infertility and mortality in up to 6% of cases. Prompt diagnosis and management are crucial to remove the placenta after delivery and stop ongoing blood loss. With proper care, most mothers recover well. But untreated retained placenta can have tragic consequences due to its risks of substantial bleeding, infection and complications.