The term “placenta scab” refers to the natural process where the top layer of the uterine lining, known as the decidua, sheds away after childbirth. This shedding is a normal part of the postpartum healing of the site where the placenta was attached. The body must efficiently heal this internal area without forming scar tissue, which would compromise future pregnancies.
The Placental Site: An Internal Wound
The uterus is left with a considerable internal wound after the placenta detaches from the wall, an area that can be about the size of a dinner plate immediately following delivery. The muscular wall of the uterus begins to contract rapidly, reducing the size of this open area and clamping down on blood vessels to prevent hemorrhage.
This healing occurs through exfoliation, where the superficial layer of the decidua is shed gradually. Exfoliation prevents the deep layers of the uterine muscle from scarring, ensuring the uterus remains flexible and functional for future pregnancies. The gradual shedding of this tissue, along with blood and mucus, is what makes up the discharge experienced during postpartum recovery.
The Timeline for Healing and Detachment
The complete healing of the placental site generally takes about four to six weeks, aligning with the overall duration of postpartum discharge. The specific event referred to as the “placenta scab falling off” typically occurs much earlier, usually between seven and fourteen days after birth. This event marks the separation of the large, main section of the superficial decidua layer from the uterine wall.
The shedding of this layer frequently causes a temporary increase in vaginal bleeding, sometimes described as a sudden gush or a return to bright red flow. This secondary bleeding can be startling, especially if the discharge had already begun to lighten in color and volume.
Physical activity can influence the amount of this bleeding. Overexertion during the first few weeks postpartum may lead to an increased or heavier flow from the placental site. The renewed bleeding should be temporary, and the discharge should quickly revert to a lighter color and volume as the site continues to heal.
Monitoring Lochia: Bleeding as a Healing Indicator
The external manifestation of the internal healing process is lochia, the vaginal discharge that follows childbirth, which progresses through three distinct stages.
The initial stage, known as lochia rubra, lasts for approximately the first three to four days after delivery. This discharge is typically bright or dark red, containing blood, mucus, and tissue fragments, often with a heavy flow similar to a heavy menstrual period.
Lochia then transitions into the serosa stage, which is marked by a lighter, pinkish-brown discharge that is thinner and more watery. This stage usually begins around day four and can last for about ten days, indicating that the initial bleeding has subsided. The change in color reflects a higher proportion of white blood cells.
The final stage is lochia alba, where the discharge becomes yellowish-white due to a high concentration of white blood cells, epithelial cells, and cervical mucus. This stage can continue for up to six weeks postpartum, signifying the final phases of uterine lining regeneration and the complete healing of the placental site. The temporary return to bright red bleeding around the one-to-two-week mark is often the clearest sign that the main part of the decidua layer has exfoliated.
It is helpful to monitor the volume of discharge by noting how frequently a pad is saturated. Normal flow should gradually decrease, and clots should be small, typically no larger than a small grape or dime. If the flow increases significantly or if large clots are passed, it may be a sign of abnormal healing.
Warning Signs of Postpartum Complications
While a temporary increase in bleeding around one to two weeks is expected, certain signs indicate that medical attention is necessary. A sudden, heavy gush of blood that saturates more than one maxi pad in an hour for two consecutive hours is a cause for immediate concern, as this may signal a secondary postpartum hemorrhage. Passing blood clots that are larger than a golf ball is another specific warning sign that should prompt a call to a healthcare provider.
Other symptoms suggest an infection, such as endometritis, and are important to monitor. These include a foul or strong odor from the vaginal discharge, fever greater than 100.4 degrees Fahrenheit (38 degrees Celsius) or chills, and increasing lower abdominal pain. Any feeling of dizziness, lightheadedness, or feeling generally unwell alongside abnormal bleeding requires prompt medical evaluation.