Abnormal vaginal bleeding includes any vaginal bleeding that occurs before puberty, during pregnancy, after menopause, or between menstrual periods. During the reproductive years, vaginal bleeding occurs as normal as menstruation. However, menstrual periods are considered pathological if they are too heavy, last more than seven days, or occur every 21 days or later than the 35th day. Abnormal vaginal bleeding can occur during early pregnancy (implantation bleeding) or in the later stages of pregnancy, which can manifest as a complication. Prolonged or excessive bleeding, regardless of the cause, can lead to iron deficiency, anemia, and sometimes dangerously low blood pressure (shock). The likely causes of vaginal bleeding depend on the woman’s age. Newborn girls may have some vaginal bleeding. Before birth, they absorb estrogen through the placenta from the mother. After birth, these high estrogen levels decrease rapidly, sometimes causing some bleeding in the first 1 to 2 weeks of life. During childhood, vaginal bleeding is unusual and rare. When it occurs, the most common causes are a foreign object (such as various objects or toys in the vagina) or injury. During the reproductive years, the most common causes can be: Uterine bleeding due to ovulatory dysfunction. It occurs when the hormonal control of menstruation changes. It is more likely to occur in adolescents (when menstrual periods are just starting) or in women in their late 40s (when menstruation is coming to an end); Complications of pregnancy in a woman who does not know she is pregnant; Fibroid formations in the uterus; Bleeding when the egg is released (at ovulation) during the menstrual cycle; Using birth control pills (oral contraceptives), which can cause spotting or bleeding between periods (called breakthrough bleeding) As for bleeding after menopause, the most common cause is age-related thinning of the lining of the vagina (atrophic vaginitis) or the uterus. In women with vaginal bleeding, some characteristics are cause for concern: Loss of consciousness, weakness, dizziness, cold and sweaty skin, difficulty breathing, weak and rapid pulse (which is a manifestation of a shock state and requires emergency medical attention). Bleeding that occurs before the start of the menstrual cycle (before puberty) or after they stop (after menopause). Bleeding during pregnancy Heavy bleeding Difficulty walking or sitting in children, bruising or lacerations around the genitals or anus or mouth and/or vaginal discharge or itching (which may be signs of sexual abuse). Bleeding is considered excessive and profuse if large clots are released during menstruation. References: Vaginal Bleeding – Women’s Health Issues – MSD Manual Consumer Version (msdmanuals.com)