Placental under perfusion disorders have been implicated as risk factors for retained placenta. Some research suggests that women may be predisposed to retained placenta.
Retained placenta in a prior delivery appears to be an important risk factor for recurrence. Retained placenta requiring invasive procedures is associated with obstetrical morbidities. Of arguably greatest significance is the risk of postpartum hemorrhage, with retained placenta the second leading cause of significant and even fatal hemorrhage in the obstetric population.
Further research additionally suggests that the longer the third stage of labor, the greater the risk of postpartum hemorrhage. The authors found that both manual removal of the placenta and PPH decreased with increasing gestational age, and that the two were related. However, causal association could not be determined. If the placenta or pieces of the placenta remain in situ following attempt at manual removal, a patient may require surgical management. These can include delayed postpartum hemorrhage or endomyometritis.
Evidence of infection risk, particularly endometritis, following manual or surgical removal of retained placenta has been inconsistently demonstrated. Retained placenta is clinically diagnosed when the placenta fails to spontaneously separate during the third stage of labor, with or without active management, or in the setting of severe bleeding in the absence of placental delivery.
Selection of a clinical time definition can be based either on a population curve of observed spontaneous placental delivery times or on a time at which morbidity significantly increases. Thirty minutes have been used as a loose guideline, which comes from a study by Combs et al. This timing has been supported by other studies as well. Because PPH incidence did not increase until after 30 minutes, Combs et al recommended this timing for initiation of manual removal of the placenta.
However, this guidance is not uniformly supported. In a subsequent study by Deneux-Tharaux, surveys from 14 European countries exhibited wide variations in wait time prior to manual placental removal, largely by country but also by the hospital. Practices also varied considerably depending on whether or not the patient in question had prior epidural anesthesia. For instance, the National Institute for Health and Clinical Excellence suggests a wait time of 30 minutes in the United Kingdom prior to manual removal of the placenta, 24 while the World Health Organization guidelines propose a wait time of 60 minutes.
The most significant risk of waiting a prolonged amount of time before removing the placenta is postpartum hemorrhage. In , Magann and colleagues undertook a prospective observational study in which all women delivering vaginally were assessed for PPH.
At times the bulk of the placenta will deliver spontaneously or manually, but small portions or an accessory lobe may be retained. This may be suspected when the placenta appears fragmented after delivery or when there is ongoing heavy uterine bleeding. In this situation, the uterine cavity may be evaluated with manual exploration or with ultrasound.
The utility of ultrasound in this situation has yet to be established, with a focal endometrial mass, particularly with Doppler flow, being the findings of interest. After delivery of the infant and prior to diagnosis of retained placenta, active management is recommended to facilitate spontaneous placental separation, including oxytocin, controlled cord traction, and uterine massage.
Once diagnosed, the placenta is usually manually extracted from the uterus. Because this procedure is painful, adequate analgesia should be achieved via epidural, conscious sedation, or general anesthesia prior to an attempt at extraction. Once the patient is comfortable, she should be appropriately positioned in lithotomy.
The operator should make every attempt to wear gown and gloves and maintain sterility, both for personal and for patient protection. The provider should then use one hand to follow the umbilical cord through the vagina and cervix until the placenta is palpated. If the placenta is separated but not expelled, such as in the case of uterine atony, the tissue can be firmly grasped and brought through the cervix. Uterotonic medications, such as oxytocin, methylergonovine, carboprost, or other prostaglandins, should be given to facilitate contraction once the placenta is removed.
Nitroglycerine NTG has been used to facilitate manual extraction by relaxing uterine smooth muscle. The medication can produce hypotension and tachycardia, which can confound assessments of maternal stability. Once the placenta is delivered, uterotonics should be promptly given to restore uterine tone and avoid significant atony.
If the placenta remains attached to the uterine decidua, an attempt should be made to separate it manually. Using one hand to provide counter pressure on the fundus through the maternal abdomen, the provider should then use the internal hand to manually create a cleavage plane between the placenta with the attached decidua and the myometrium.
Once separated, the placenta can be removed as described above. If a separation plane cannot be created behind all or part of the placenta, the provider should suspect a morbidly adherent placenta MAP and prepare for potential hemorrhage.
If placental removal is refractory or only partially successful ie the placenta or parts of the placenta remain in the uterus , or if bleeding persists despite placental delivery, often the next step is surgical management with curettage. This may be best achieved in an operating room, with optimal access to surgical equipment, analgesia, and patient resuscitation aids, if needed. Suction curettage is generally used, though a sharp curette may be needed to facilitate a separation plane.
Access to uterine tamponade supplies with either a large intrauterine balloon or surgical packs should be immediately accessed in the event of hemorrhage.
Crossmatched blood products should be made imminently available if placental separation is difficult or blood loss exceeds 1 L, and the care team should attend to uterotonic administration and attention to coagulopathy as the extraction is performed.
Due to the risk of endometritis, routine antibiotics are generally administered just before or shortly after manual removal of the placenta. Patients who are febrile at the time of extraction should be fully treated for chorioamnionitis with broad-spectrum antibiotics. A systematic review by Chibueze and colleagues attempted to summarize the literature on the efficacy of antibiotics for preventing adverse maternal outcomes related to manual placenta removal following vaginal birth.
None of the three studies found evidence to suggest beneficial effects for routine antibiotic use in women undergoing intervention for retained placenta. The authors concluded that further research is required to adequately answer this question. Occasionally, a portion of placental tissue may remain in the uterus, either knowingly or unbeknownst to the providers. This can present as abnormal bleeding days to weeks after delivery and should be suspected in the setting of a delayed postpartum hemorrhage.
In a series of case reports, Lee and colleagues reported a higher risk of complications with blind curettage compared to hysteroscopic morcellation. The photo on the left A shows a retained portion of placenta approximately 8 weeks after delivery. The photo on the right B shows the same uterus following hysteroscopic morcellation of the retained placenta.
Other studies have examined alternative, nonsurgical, management for retained placenta, none of which have been successful. The authors found that oral misoprostol reduced neither the need for manual removal nor the overall amount of blood loss. Both groups were observed for additional 45 mins after administration of misoprostol or placebo. For a time, umbilical vein oxytocin was thought to be a promising alternative or adjunct to manual extraction of the placenta.
A Cochrane Review summarized available data on the subject to assess the use of umbilical vein oxytocin either alone or in conjunction with intravenous oxytocin to reduce the need for manual removal of retained placenta. In the unusual event that manual extraction does not result in delivery of the entire or partial placenta, MAP must be considered as an etiology.
The PAS, which includes accreta, increta, or percreta, can be causes of significant surgical and hemorrhagic morbidity on the labor and delivery floor 4 , 37 Figure 2. While PAS is relatively rare, particularly in the absence of a placenta previa, it can occur at vaginal delivery when there is no previa. Given the excess morbidity, providers should consider this pathology when a placenta is retained in the setting of significant PAS risk factors.
These include prior uterine surgeries, including hysteroscopic resections, IVF conception, a history of intrauterine adhesions, or a prior history of MAP or pathologic findings of accreta.
Magnetic resonance image showing a portion of retained placenta 6 weeks postpartum. The arrow indicates an area where the light-gray placenta is deeply invasive into the darker-gray myometrium. Placenta accreta spectrum was confirmed pathologically following hysterectomy. As a result, premature labor may lead to a retained placenta. Doctors do everything in their power to prevent a retained placenta by taking actions that hasten complete delivery of the placenta after the birth of the baby.
These steps are as follows:. These are all standard steps that your doctor may perform before you deliver the placenta. After childbirth, your doctor will also recommend massaging your uterus to encourage contractions that stop the bleeding and allow the uterus return to return to a small size.
In the unfortunate event that your cord snaps or your cervix closes too quickly after the oxytocin injection, consider a physiological third stage if you conceive again. If you allow the placenta to deliver naturally, the cervix will more than likely close at the appropriate time, instead of closing too quickly. Discuss your options with your doctor. However, keep in mind that the prolonged use of Syntocinon artificial oxytocin during labor has contributed to retained placentas.
This concern may develop if your labor is induced or sped up. Begley C. Physiology and care during the third stage of labor.
Myles Textbook for Midwives 16th ed. Edinburgh: Churchill Livingstone, Risk factors for a prolonged third stage of labor and postpartum hemorrhage. South Med J 2 Coviello, E. Risk factors for retained placenta.
Retained Placenta. What Is a Retained Placenta? Labor takes place in three stages: The first stage of labor begins with contractions that indicate that the uterus is preparing to deliver a baby. Once a woman has given birth, the second stage of labor is complete.
Medical personnel assists the managed approach and usually, occurs when a shot is administered to the thigh while the baby is being born to cause the woman to expel her placenta. What Are the Types of Retained Placenta? Retained placenta can be broken into three distinct classifications: Placenta Adherens Placenta Adherens occurs when the contractions of the womb are not robust enough to completely expel the placenta.
Placenta Accreta When the placenta attaches to the muscular walls of the uterus instead of the lining of the uterine walls, delivery becomes harder and often results in severe bleeding. What Causes a Retained Placenta? Here are common circumstances that result in a retained placenta: A Placenta Percreta occurs when the placenta grows all the way through the wall of the womb.
In rare situations, this happens because the placenta has become deeply embedded within the womb. Placenta Accreta takes place when the placenta has become deeply embedded in the womb, possibly due to a previous cesarean section scar. A Trapped Placenta results when the placenta detaches from the uterus but is not delivered.
Instead, it becomes trapped behind a closed cervix or a cervix that has partially closed. After having five fist-sized blood clots removed, McCain was sent home—only for the hemorrhaging to begin two months later.
After she sought medical help to find out what was going on, it turned out she had a piece of placenta the size of two golf balls left in her uterus. She subsequently had the remaining placenta removed. The medical term for what McCain was dealing with is called a " retained placenta. Usually the placenta—the organ that forms in the uterus at pregnancy and provides oxygen and nutrients for the developing baby—delivers itself about 30 minutes after the baby is born.
Typically the ob-gyn will examine it to make sure the entire placenta is out. But it's not uncommon for some to be missed by the doctor and left behind.
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