Misoprostol is a synthetic medication originally developed for preventing and treating stomach ulcers. In reproductive health, it is widely utilized for its ability to stimulate the uterus. This medicine is commonly used to manage miscarriages or induce medical termination of a pregnancy by causing the uterus to empty its contents. Because of this intended effect, bleeding is not a side effect but rather an expected and necessary outcome of the treatment.
How Misoprostol Induces Bleeding
Misoprostol works by increasing the strength and frequency of uterine contractions. It binds to the muscle cells of the uterus, causing forceful, rhythmic contractions. These contractions lead to the expulsion of the uterine lining and any tissue present, similar to a very intense menstrual period. The medication also causes the cervix to soften and dilate, facilitating the passage of tissue. This combined action of contracting the muscle and opening the cervix produces the bleeding experienced after taking the medicine.
Characteristics of Expected Bleeding and Duration
The bleeding following Misoprostol use is expected to be significantly heavier than a typical menstrual period. This heavy flow usually begins within a few hours of taking the medication. During the most active phase, it is normal to soak through several maxi pads and pass large blood clots.
The clots can be quite large, often reaching the size of a golf ball, and sometimes even up to the size of a lemon. Passing these large clots is a sign that the uterus is actively shedding its contents and that the medicine is working as intended. This most intense period of heavy bleeding and cramping typically lasts for approximately four to six hours, during which time the pregnancy tissue is usually expelled.
The heaviest bleeding generally slows substantially once the bulk of the tissue has been passed. After this initial peak, the bleeding transitions into a pattern similar to a heavy period, which may last for one to three days. Following this, lighter bleeding or spotting can continue intermittently for several weeks, sometimes lasting up to eight weeks in total.
It is common for the bleeding to stop and start again during this recovery period, which does not necessarily indicate a complication. Individuals commonly experience strong, sometimes severe, uterine cramping that is more intense than typical period pain. Other common side effects include nausea, vomiting, diarrhea, chills, and a low-grade fever, which should subside within 24 hours.
Signs That Require Immediate Medical Attention
While heavy bleeding is expected, specific signs indicate the blood loss is excessive and requires immediate medical attention. Unsafe bleeding is defined as soaking two or more full-sized maxi pads in one hour, for two consecutive hours. This metric suggests a rate of blood loss that warrants contacting a healthcare provider immediately.
Excessive blood loss is also indicated by the passage of unusually large or frequent clots. While clots up to the size of a lemon are normal, passing larger clots or a high volume of large clots for several hours is concerning. Accompanying signs of significant blood loss, such as feeling lightheaded, dizzy, faint, or experiencing a rapid heart rate, also require urgent care.
Signs of a possible infection, though uncommon, should prompt immediate medical contact. These include a high fever (above 100.4°F or 38°C) that lasts for more than 24 hours. A foul-smelling vaginal discharge is another symptom that may signal an infection and requires evaluation.
Unrelenting, severe abdominal or back pain not alleviated by over-the-counter pain medication is a warning sign. If no bleeding or only very light spotting occurs within 24 hours of taking Misoprostol, contact a provider. This may indicate incomplete treatment or suggest an underlying condition, such as an ectopic pregnancy.