Menstruation, commonly known as a period, is a natural monthly process for individuals with a uterus, usually starting around the ages of 12 to 13. It involves the shedding of the uterine lining, resulting in a discharge of blood and tissue through the vagina. The characteristics of period blood, including its color, texture, and flow duration, can be insightful indicators of reproductive health.
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Understanding black period blood: Learn about the common and less common reasons for dark menstrual blood.
Menstrual blood color is not always a consistent red. It can vary across a spectrum of shades, from vibrant red and orange to brown, and sometimes even black. It’s important to clarify that black period blood isn’t truly black but rather appears this way due to its deep, dark hue. While these color variations are often within the range of normal, the appearance of black period blood can sometimes signal an underlying health issue that may require medical evaluation.
Decoding Black Period Blood and Vaginal Discharge
Black period blood typically occurs when blood takes longer to exit the uterus. This extended time allows for oxidation, a natural chemical process that darkens blood when it’s exposed to oxygen. Oxidized blood turns a dark brown or blackish color, similar to the appearance of coffee grounds.
Experiencing black period blood or vaginal discharge is not always a cause for alarm. It is often observed at different points within the menstrual cycle, particularly at the beginning and end of menstruation.
Vaginal discharge, in general, can provide valuable clues about your overall health. When it comes to black period blood, there are several potential explanations. Here are eight common reasons why you might see black period blood:
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1. Start or End of Your Period
Menstrual flow isn’t constant throughout your period. It tends to be lighter and slower at the onset and conclusion of menstruation. When blood flow is slow, it takes longer to leave the body. This extended time allows the blood to oxidize, resulting in the dark, black appearance of period blood. Think of it like old blood – it has had more time to react with oxygen. If you notice black blood at the very beginning or end of your period, it’s often just a sign of older blood being expelled.
2. A Foreign Object in the Vagina
Sometimes, black period blood can indicate the presence of a foreign object within the vagina. A common example is a forgotten tampon, especially if left in place for an extended period.
Other items that can become lodged in the vagina include condoms, sex toys, contraceptive devices like sponges, diaphragms, rings, and cervical caps. These objects can irritate the vaginal lining and potentially lead to an infection if left inside for too long. Besides black period blood, an infection might manifest with additional symptoms, such as:
- Unpleasant vaginal odor
- Vaginal discomfort or itching
- Genital rash or swelling
- Fever
- Painful urination
- Pelvic or abdominal pain
If you observe black period blood accompanied by any of these symptoms and suspect a foreign object might be lodged in your vagina, it’s crucial to seek medical attention promptly. In rare circumstances, a retained foreign object can lead to a severe, life-threatening infection known as toxic shock syndrome (TSS).
Normal period blood color: Typically, healthy period blood is red and not black.
3. Retained Period Blood (Hematocolpos)
Retained menses, also known as hematocolpos, occurs when menstrual blood is unable to exit the vaginal canal and accumulates within the vagina. Over time, this trapped blood oxidizes and darkens, turning black.
This condition is frequently caused by congenital abnormalities of the vaginal septum or hymen, which can obstruct the flow of menstrual blood. Less commonly, conditions like cervical agenesis (absence of a cervix) or cervical atresia (a surgical complication) can also lead to retained menses. Hematocolpos is often diagnosed during adolescence because it’s frequently linked to congenital abnormalities.
A significant blockage can result in amenorrhea, the absence of menstruation. Other symptoms associated with hematocolpos can include cramping pain in the lower abdomen and adhesions.
4. Cervical Cancer (Rare)
In very rare instances, black period blood, particularly when combined with abnormal bleeding after intercourse or between periods, might be an early warning sign of cervical cancer.
Early stages of cervical cancer often present without noticeable signs or symptoms. However, as cervical cancer progresses, more pronounced symptoms can develop. These may include heavy, watery, bloody vaginal discharge with a foul odor and vaginal bleeding that can eventually darken to brown or black period blood. Other indicators of advanced cervical cancer include:
- Persistent fatigue
- Periods that are longer or heavier than usual
- Pain during sexual intercourse
- Bleeding during or after sex
- Unexplained weight loss
- Pelvic pain
- Difficulty urinating
- Difficulty with bowel movements
- Swelling in the legs
It’s crucial to remember that black period blood is rarely the sole symptom of cervical cancer, and this is a less common cause. However, if you experience black period blood alongside other concerning symptoms, especially unusual bleeding, it is vital to consult a healthcare provider for evaluation.
Consulting a doctor: If you are concerned about black period blood, seeking medical advice is important.
5. Postpartum Lochia
Lochia is the normal vaginal bleeding that occurs for several weeks after childbirth, typically lasting six to eight weeks. Initially, lochia is characterized by a heavy flow that is reddish in color and may contain small blood clots. Over the first few days postpartum, as the flow slows, some of this blood can oxidize. This oxidation can result in a very dark, almost black appearance, particularly in the early postpartum period when the blood volume is higher.
As time passes, the color of lochia gradually lightens, transitioning to yellow or creamy before eventually ceasing altogether. It’s important to monitor lochia after childbirth. If you experience bright red lochia, notice clots larger than plum-sized, or if there is a foul-smelling discharge in the weeks following delivery, it’s essential to consult a healthcare provider promptly.
6. Miscarriage
Miscarriage, or pregnancy loss, can occur within the first 20 weeks of gestation. Dark red spotting, which may sometimes be mistaken for black period blood, can be an indicator of early miscarriage. It’s estimated that a significant percentage of pregnancies, around 10%, end in miscarriage.
In some cases of miscarriage, black period blood or dark spotting may be the only noticeable symptom initially, without heavy bleeding or significant pain. Occasionally, a missed miscarriage can occur, where the embryo ceases to develop but is not expelled from the body. This type of miscarriage might only be detected through an ultrasound.
If you suspect you might be pregnant and experience black period blood, particularly if accompanied by other miscarriage symptoms like cramping or loss of pregnancy symptoms, it’s crucial to seek medical attention.
7. Implantation Bleeding (Rarely Black)
Implantation bleeding can sometimes be mistaken for dark brown or even black period blood, although true black blood from implantation is rare. Implantation bleeding is light spotting that can occur about 10 to 14 days after fertilization when a fertilized egg implants into the uterine lining.
The flow associated with implantation bleeding is typically very light and lasts only a day or two. If this small amount of blood takes an extended time to travel out of the vagina, it could potentially oxidize and appear dark brown or, in very rare instances, black. Other early pregnancy signs, such as breast tenderness and fatigue, may accompany implantation bleeding.
It’s important to note that not all pregnancies involve implantation bleeding. If you suspect you could be pregnant or experience any unusual bleeding, consulting a healthcare provider is always recommended to confirm pregnancy and rule out any other potential issues.
8. Sexually Transmitted Infections (STIs)
Black period blood has been linked to certain sexually transmitted infections (STIs) like chlamydia and gonorrhea. Dark brown or black discharge can sometimes be a symptom of an STI, often accompanied by other symptoms, such as:
- Vaginal discharge with a foul odor
- Pain or burning sensation during urination
- Painful sexual intercourse
- Bleeding during or after sex
- Pelvic pressure or pain
- Vaginal itching
- Spotting between periods
Untreated STIs can spread and lead to pelvic inflammatory disease (PID), an infection affecting the cervix, uterus, and other reproductive organs. PID can result in serious complications, including chronic pelvic pain and infertility.
Furthermore, black or dark brown period blood can sometimes be associated with other underlying health conditions such as endometriosis, uterine fibroids, endometrial polyps, or ectopic pregnancy.
Treatment Options for Black Period Blood
If you have any concerns about black period blood or are unsure of the cause, it’s essential to consult a healthcare provider for proper diagnosis and guidance. Treatment approaches for black period blood are determined by the underlying cause:
- Foreign object: If a foreign object is lodged in the vagina, removal by a healthcare professional is necessary. Symptoms like fever, pain, and dark discharge may accompany this situation.
- STIs and PID: These infections are typically treated with antibiotics. It’s crucial to adhere to the prescribed treatment regimen and complete the entire course of antibiotics.
- Missed miscarriage: While some missed miscarriages resolve naturally, most require medical intervention. Options include medication or a dilation and curettage (D&C) procedure to remove remaining tissue from the uterus.
- Retained menses: Surgery may be necessary to correct the anatomical issues causing the blockage and retained menstrual blood.
- Cervical cancer: Treatment for cervical cancer is complex and individualized, often involving a combination of surgery, chemotherapy, and radiation therapy.
When to Seek Medical Advice
Normal menstrual cycles typically last two to seven days and occur every 21 to 35 days. Black period blood that occurs outside of this typical window may be considered irregular and warrants discussion with a healthcare provider.
If you experience dark discharge during pregnancy, after childbirth, or as you approach menopause, it’s important to seek medical advice, as it could indicate a more serious underlying condition. Black period blood accompanied by any of the following symptoms also requires medical evaluation:
- Heavy vaginal discharge
- Foul-smelling discharge
- Vaginal itching
- Pelvic cramping, pain, or fever
Discover more articles: Period Blood Colors: A Complete Overview Spotting vs. period vs. bleeding: Know the difference
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Key Takeaway
Black period blood is sometimes a normal variation, particularly at the start or end of your period, but in some cases, it can be a symptom of an underlying health issue. If you have any concerns or suspect any of the conditions discussed, it’s always best to make an appointment with a healthcare provider for proper assessment and personalized guidance. Treating black period blood effectively depends on identifying and addressing the root cause.
References
“Menstruation in Girls and Adolescents: Using the Menstrual Cycle as a Vital Sign.” ACOG, 2017, www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2015/12/menstruation-in-girls-and-adolescents-using-the-menstrual-cycle-as-a-vital-sign.
“Bleeding During Pregnancy.” ACOG, 2019, www.acog.org/Patients/FAQs/Bleeding-During-Pregnancy.
“Retained Tampon or Other Object.” Healthdirect, Healthdirect Australia, 2019, www.healthdirect.gov.au/retained-object-or-tampon.
Rezai, Shadi, et al. “Hematometra And Hematocolpos, Secondary To Cervical Canal Occlusion, A Case Report And Review Of Literature.” ResearchGate, Obstetrics and Gynecology International, Mar. 2017, www.researchgate.net/publication/310798780_Hematometra_And_Hematocolpos_Secondary_To_Cervical_Canal_Occlusion_A_Case_Report_And_Review_Of_Literature.
Tobah, Yvonne Butler. “Implantation Bleeding: Normal in Early Pregnancy?” Mayo Clinic, Mayo Foundation for Medical Education and Research, 9 May 2019, www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/implantation-bleeding/faq-20058257.
Cleveland Clinic medical professional. “Abnormal Menstruation (Periods): Types, Causes & Treatment.” Cleveland Clinic, 25 Aug. 2018, my.clevelandclinic.org/health/diseases/14633-abnormal-menstruation-periods.
Munro, Malcolm Gordon, et al. “FIGO Classification System (PALM-COEIN) for Causes of Abnormal Uterine Bleeding in Nongravid Women of Reproductive Age.” ResearchGate, International Journal of Gynaecology and Obstetrics: the Official Organ of the International Federation of Gynaecology and Obstetrics, Feb. 2011, www.researchgate.net/publication/49942833_FIGO_classification_system_PALM-COEIN_for_causes_of_abnormal_uterine_bleeding_in_nongravid_women_of_reproductive_age.
Cleveland Clinic medical professional. “Physical Changes after Child Birth.” Cleveland Clinic, 1 Jan. 2018, my.clevelandclinic.org/health/articles/9682-pregnancy-physical-changes-after-delivery.
Mayo Clinic Staff. “Polycystic Ovary Syndrome (PCOS).” Mayo Clinic, Mayo Foundation for Medical Education and Research, 29 Aug. 2017, www.mayoclinic.org/diseases-conditions/pcos/symptoms-causes/syc-20353439.
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