Bloody vaginal discharge can have many different causes, ranging from ovulation to disease. While the majority of the causes are not life threatening, a medical professional should evaluate unexpected or extremely heavy discharge. Common causes of bloody discharge include menstruation, pregnancy, sexually transmitted diseases, the use of birth control, and trauma.
Normal vaginal discharge is a healthy part of a woman’s reproductive system, as it helps keep the vagina clean and regulates its pH balance. Normal discharge is typically clear, milky white, or yellowish in color. While the consistency is usually thin and runny, it can look and feel thicker or stickier during ovulation. Bloody vaginal discharge can be normal as well, but typically signals an underlying medical condition or trauma.
Menstruation, the shedding of the lining of the uterus, is the most common cause of normal bloody vaginal discharge. The bleeding typically lasts three to four days, with the heaviest days in the middle. The strength of the blood flow and length of menstruation differs between women; excessively heavy bleeding or a longer than usual cycle may indicate another underlying condition.
Some women experience normal bloody vaginal discharge during pregnancy, especially in the beginning when the egg implants into the uterus. Implantation bleeding typically occurs between six to 12 days after fertilization and appears as a pinkish or brown shade. Additional light spotting throughout the pregnancy is typically normal, but a doctor should still check it out. Heavy bloody vaginal discharge can indicate miscarriage or ectopic pregnancy.
Gonorrhea, a sexually transmitted disease, can cause abnormal bloody vaginal discharge. Gonorrhea can affect any sexually active person, but is most common in teenagers and young adults. If left untreated, the disease can lead to pelvic inflammatory disease that can cause permanent damage to the reproductive organs. Gonorrhea can also spread to the blood and joints and become life threatening. The disease responds well to antibiotics when caught in the early stages.
Fluctuating hormones, especially from medications, can cause bloody vaginal discharge. For example, stopping birth control pills or hormone replacement therapy can cause withdrawal bleeding as the body tries to relearn how to manage cycles on its own again. Bleeding can also occur while taking birth control. It is particularly common in patients using contraceptive injections, where bleeding can occur between periods for several months.
Numerous conditions of the reproductive system can cause bloody vaginal discharge. Trauma to the vaginal area, such as through sexual assault, can also cause this type of discharge. Vigorous consensual sexual intercourse can occasionally cause small tears in the lining of the vaginal walls as well, which may cause some temporary light spotting.
Other reproductive conditions, including ovarian cysts, endometriosis, and several different types of cancer, all have the potential to cause abnormal bleeding between cycles. Inflammatory diseases such as vaginitis and cervicitis may also present with this symptom. These conditions can become life threatening when left untreated.