The placenta is a temporary organ that serves as the life support system for the fetus throughout pregnancy, facilitating the exchange of oxygen, nutrients, and waste products. The process of delivering this organ is known as the third stage of labor, which begins immediately after the baby is born and ends with the expulsion of the placenta and its attached membranes. This final phase requires specific management to ensure the completion of the birth process. Successful expulsion allows the uterus to contract, preventing excessive post-birth bleeding.
Timing and Separation Signs
The placenta typically separates from the uterine wall and delivers spontaneously within five to 30 minutes following the birth of the baby. Uterine contractions continue after birth, causing the placental site to shrink and creating a shearing force that prompts detachment. If the placenta is not delivered within 30 minutes, the risk of significant postpartum hemorrhage increases, often requiring medical intervention.
Several physical signs indicate that the placenta has successfully separated and is ready to be expelled. The most reliable cue is the lengthening of the umbilical cord as the detached placenta moves down into the lower uterine segment or vagina. The uterus also changes shape, becoming firmer and more globular upon palpation of the abdomen. Finally, a sudden gush of blood can occur as the placenta detaches.
Delivery Methods: Active vs. Expectant Management
There are two primary strategies for managing the third stage of labor. Active management is the more common approach in hospital settings and is designed to significantly reduce the risk of postpartum hemorrhage. This strategy involves three main interventions: the prophylactic administration of a uterotonic drug (such as oxytocin) immediately after birth, controlled cord traction, and immediate fundal massage.
The uterotonic drug causes the uterus to contract strongly and quickly, hastening separation and expulsion. Studies show that active management is associated with a reduced risk of blood loss exceeding 500 milliliters compared to the hands-off approach. However, active management may carry an increased risk of minor side effects like nausea and vomiting.
In contrast, expectant management (sometimes called physiological management) is a non-interventional approach that relies on the body’s natural processes. This method involves waiting for spontaneous signs of separation and allowing gravity and the patient’s gentle pushing efforts to expel the placenta. Expectant management is often preferred in low-intervention settings. Practices like skin-to-skin contact and immediate breastfeeding are encouraged to stimulate the natural release of oxytocin, which promotes uterine contractions.
The Physical Steps of Delivery
Once the placenta has separated, its physical delivery involves a coordinated effort between the patient and the healthcare provider. The patient is encouraged to bear down gently with the next contraction, similar to pushing during the second stage of labor. The placenta, which is soft, usually slides out with minimal effort once it has descended into the vagina.
Under active management, the provider uses controlled cord traction to guide the placenta out. This involves applying gentle, steady tension to the umbilical cord while simultaneously applying counter-pressure to the abdomen just above the pubic bone. This counter-pressure, known as “guarding,” stabilizes the uterus and prevents the risk of uterine inversion, a rare but serious complication.
The provider may also perform fundal massage, which is the gentle rubbing of the abdomen over the uterus. This action encourages the uterine muscle to contract down firmly. This helps to shear the placenta away and constrict the blood vessels at the attachment site. This manual stimulation aids both separation and expulsion, ensuring the uterus remains firm.
Immediate Post-Delivery Care and Inspection
After the placenta is fully expelled, immediate post-delivery care focuses on ensuring maternal safety. The provider continues fundal massage to encourage the uterus to contract firmly and achieve involution (shrinking back toward its pre-pregnancy size). A well-contracted uterus acts as a natural ligature, clamping down on the open blood vessels where the placenta was attached and preventing excessive bleeding.
A careful inspection of the placenta and its attached membranes confirms that the organ is complete and no fragments remain inside the uterus. Retained placental tissue interferes with the uterus’s ability to contract properly, leading to delayed or excessive postpartum hemorrhage and infection. The provider examines both the maternal side (looking for all cotyledons) and the fetal membranes for tears or missing pieces.
Continuous monitoring of the patient’s vital signs (including blood pressure and pulse) and the amount of blood loss is maintained for at least the first hour after delivery. This close observation is part of the fourth stage of labor, which immediately follows the delivery of the placenta. This final stage ensures the patient is stable before transitioning to postpartum recovery.