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Vaginal Bleeding During and After Sex: Causes and Risk Factors

Have you ever experienced bleeding during or after sex? It’s actually more common than you might think. Today, we’ll investigate possible reasons for heavy bleeding after sex and identify risk factors associated with bleeding during sex.

What causes bleeding after sex?

Among other things, bleeding after sex can be a side effect of menopause, or it can be a sign of a serious condition. Vaginal bleeding after sex is also called postcoital bleeding and can be caused by:

  • Cervical inflammation (cervicitis) — Cervicitis can be ongoing and symptomless. It can also be caused by a sexually transmitted infection that needs to be treated, like chlamydia or gonorrhea. 
  • Vaginal dryness — During menopause, the hormones in your body change. The level of estrogen decreases and may lead to a decrease in vaginal fluid, resulting in vaginal dryness. Because of this, during sex, the friction can irritate the tissues that line the vagina and cause pain. This can be alleviated with the use of some water-soluble lubricant. 
  • A cervical polyp — Polyps are growths that are usually small (1 to 2 centimeters) and appear on the cervix where it meets the vagina. Most polyps are non-cancerous and can be removed by your OB-GYN during an appointment.
  • Normal uterine bleeding — This can happen just before or just after your expected period. At the very beginning or the very end of your period, it’s normal to experience light bleeding after sex. This may appear as light spotting.
  • Cancer — Cancer can affect the vagina, cervix, and uterus. Make sure you schedule regular appointments with your health care provider for Pap smears and pelvic exams, which can help detect early signs of cancer.

While some of the causes of bleeding during or after sex don’t pose a serious threat, sometimes vaginal bleeding after sex can be a sign of a more serious issue.

Causes of bleeding during sex

Vaginal bleeding during sex can be caused by many of the same things that can cause bleeding after sex. These include infection, vaginal trauma due to dryness, cervical polyps, menopause, and cancer. However, there are some other conditions that can cause bleeding during sex specifically:

  • Endometriosis — This medical condition causes endometrial-like tissue to grow where it isn’t supposed to (outside the uterus). Because of this, many people with endometriosis report irregular cycles and bleeding or spotting between periods. This can cause bleeding during and after sex.
  • Contraception — Whenever you start or change your type of contraception, bleeding can happen between periods. However, if you experience heavy bleeding during sex, make sure to talk to a health care provider about it. 
  • Pregnancy — About 15 to 25 percent of pregnant people experience bleeding in the first trimester. It can occur 10 to 14 days after fertilization, when the fertilized egg implants in the lining of the uterus, and is known as implantation bleeding. It’s possible to have spotting or light bleeding during or after sex while pregnant. In early pregnancy, more blood vessels are developing in the cervix; they can be damaged more easily by friction, causing bleeding during sex. 
  • Postpartum — The uterus and vagina can take six to eight weeks to completely heal after childbirth. During this time, the bleeding after delivery (lochia) will slow down and may even stop for a few days. Even after stopping briefly, it can start up again unexpectedly.
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Bleeding after anal sex: what are the possible reasons?

The tissue that lines the rectum is very sensitive and tears easily. Bleeding after anal sex can be caused by the insertion of a finger, penis, or sex toys. Bleeding after anal sex can also be caused by friction, rough or aggressive intercourse, or by rough edges on objects that may be inserted through the anus into the rectum.

If you’re bleeding after anal sex, you may need to add or use more water-soluble lubricant to prevent these types of injuries. Bleeding from sex can lead to additional health concerns. This is even more important if you bleed during or after sex every time you and your partner engage in intercourse. If this happens, you may need to visit a health care provider and/or make some changes to the way you have sex.

How long after sex does implantation bleeding occur?

It’s difficult to determine exactly how long it takes after conception for implantation bleeding to occur. During a normal menstrual cycle, the optimal time to conceive is usually the 5–6 days of the fertile window. The human ovum (the egg cell) lives up to 24 hours. However, sperm can live up to five days in the female reproductive organs. This means that you could have sex that leads to pregnancy up to five days before ovulation.

Once an egg has been fertilized, it undergoes multiple stages of cell division before it’s ready to start the implantation process. First, the fertilized egg enters the uterine cavity about four days after ovulation, and the endometrium becomes receptive to implantation six to eight days after ovulation, remaining receptive for about four days. The implantation itself occurs 6 to 10 days after ovulation and lasts for four to five days. It may result in some light bleeding or spotting, which typically occurs about 10 to 14 days after conception, but you should not experience implantation bleeding as soon as one or two days after sex. So if it happens, implantation bleeding will be the result of sex that occurred about 10 to 14 days ago. 

Bleeding after sex during pregnancy: Is it a reason for concern?

Light bleeding during the first 12 weeks of pregnancy is not uncommon. The cause of this spotting 10 to 14 days after conception may be the egg implanting into the blood-rich uterine lining. In this case, light bleeding after sex should not be concerning. 

Most miscarriages occur in the first trimester. If you’re pregnant and experience any bleeding and/or cramping, contact your health care provider immediately. 

After 12 weeks, miscarriage is less likely, and light bleeding after sex (spotting) is fairly common in the second trimester. This is because the cervix and uterus have an increased amount of blood supplying these areas. Because of this, it may be easier for small blood vessels to be damaged during intercourse. 

During pregnancy, light bleeding after sex without cramps may be caused by something making contact with your cervix. To help alleviate this, try different sex positions that might be more comfortable. If you have any concerns at all, it’s best to speak to a health care provider.

Heavy bleeding every time after sex: When to see a health care provider

Bleeding after sex can be fairly common. Health care providers tend to be more concerned when a pregnant person is bleeding after sex or when they are postmenopausal and bleeding after sex. However, heavy bleeding after sex is only normal if it is related to your period. 

Pay attention to how often you need to change your pad or tampon and if you are passing any clots. If you’re experiencing heavy bleeding after sex that’s not related to your period, it’s important to seek medical attention as soon as possible. This is especially true if you need to change your pad or tampon every hour and/or are passing clots larger than a quarter. If you cannot get in to see a health care provider, a visit to the emergency department may be necessary.

Sapra, Katherine J., et al. “Signs and Symptoms of Early Pregnancy Loss: A Systematic Review.” SAGE Journals, 23 June 2016, journals.sagepub.com/doi/10.1177/1933719116654994.

UCSF Health. “Conception: How It Works.” Ucsfhealth.org, UCSF Health, 31 Oct. 2019, www.ucsfhealth.org/education/conception-how-it-works.

Mayo Clinic Staff. “Vaginal Bleeding.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 23 Apr. 2019, www.mayoclinic.org/symptoms/vaginal-bleeding/basics/definition/sym-20050756.

“Сhapter 17: Non-Menstrual Vaginal Bleeding Management in Primary Care.” Women's Health in Primary Care, by Anne Connolly and Amanda Britton, Cambridge University Press, 2017, pp. 138–140.

Sapra, Katherine J, et al. “Signs and Symptoms of Early Pregnancy Loss.” Reproductive Sciences (Thousand Oaks, Calif.), SAGE Publications, 27 Sept. 2016, www.ncbi.nlm.nih.gov/pmc/articles/PMC5933199/.

“Bleeding During Pregnancy.” ACOG, Sept. 2019, www.acog.org/womens-health/faqs/bleeding-during-pregnancy.

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