Certain amount of vaginal discharge is normal. However, in order to be considered normal, it has to be transparent or slightly white, without aggressive odor and in a low amount. When vaginal discharge becomes brown or red, it usually means that it is mixed with blood. There are various physiological as well as pathological factors can cause the occurrence of bloody or brown discharge between periods and here are the most common of them.
Pregnancy
In the early stage of pregnancy, between 6 and 12 days after fertilization, some women can experience the occurrence of brown or bloody vaginal discharge. This is perfectly normal and it is a consequence of implantation process. Namely, the embryo has to implant into the wall of uterus which produces a small amount of blood.
Sexually Transmitted Diseases (STD)
Inflammation of vaginal mucosa caused by STDs, such as gonorrhea and chlamydial infections, can also cause brown or bloody vaginal discharge. In these cases, changed vaginal discharge is associated with other symptoms including painful urination, aggressive odor of vaginal discharge, redness of vagina and vulva, itching, and irritation. In rare situations, brown/bloody vaginal discharge can be the only symptom of infection. If you have these or similar problems, you need to visit your doctor in order to obtain antibiotics.
Cervical Polyps
Cervical polyps are abnormal growths on the surface of cervix. They have a very fragile structure, so they can be the source of bleeding during or between periods. The blood is mixed with normal vaginal discharge, thus producing bloody or brown discharge. Women with cervical polyps often complain about pain in lower abdomen, discomfort, and unusual patterns of bleeding.
Other benign growths that can also cause these symptoms include cysts, endometriosis, and fibroids.
Cervical Cancer
Cervical cancer can cause unusual patterns of bleeding both during and between periods. It is a very serious condition with high mortality rate if not detected in early phases, so every unusual bleeding should be profoundly investigated.
Birth Control Pills
Some women experience occasional occurrence of bloody vaginal discharge related to birth control pills. These pills can cause the disturbances in hormonal status, especially during withdrawal, thus causing unusual bleeding. This is not harmful and you don't need to worry about any consequences of this bleeding, but you should always withdraw according to scheme proposed by your doctor.
There are also other causes such as mechanical trauma to the vagina and cervix that can cause brown/bloody discharge.
As you can see above, the only causes of bloody vaginal discharge between periods that are considered normal are related to early pregnancy.
- Katz VL. Benign gynecologic lesions: Vulva, vagina, cervix, uterus, oviduct, ovary. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM, eds. Comprehensive Gynecology. 5th ed. Philadelphia, Pa: Mosby Elsevier 2007:chap 18.
- Harville, E.W., Wilcox, A.J., Baird, D.D., Weinberg, C.R. (2003). Vaginal bleeding in very early pregnancy. Hum Reprod. 18(9):1944-7.
- Photo courtesy of SteadyHealth