Bleeding Between Periods: When Is It Normal and When Is It Not?

Bleeding between periods refers to any vaginal bleeding that occurs outside your regular menstrual period. This includes:

• Spotting, light bleeding that doesn't require a pad or tampon
• Breakthrough bleeding, heavier bleeding between periods
• Bleeding after sex, which can occur separately or alongside other intermenstrual bleeding

The blood may appear pink, red, or brown depending on how fresh it is.

Some causes of intermenstrual bleeding are generally not concerning:

• Ovulation spotting, some women experience light bleeding around ovulation (mid-cycle), caused by hormonal fluctuations
• Starting or changing contraception, breakthrough bleeding is common in the first few months of using hormonal contraceptives
• Implantation bleeding, light spotting can occur when a fertilised egg implants in the uterus, typically around the time of an expected period
• Perimenopause, irregular bleeding is common as hormone levels fluctuate in the years leading to menopause
• Minor cervical irritation, from sex or a cervical screening test

Several conditions can cause bleeding that warrants medical assessment:

• Cervical or endometrial polyps, benign growths that can cause irregular bleeding
• Fibroids, non-cancerous growths in or around the uterus
• Endometriosis, where tissue similar to the uterine lining grows outside the uterus
• Hormonal imbalances, affecting ovulation and the menstrual cycle
• Sexually transmitted infections (STIs), such as chlamydia, which can cause inflammation
• Cervical ectropion, where cells from inside the cervix appear on the outside
• Thyroid disorders, can disrupt menstrual regularity
• Polycystic ovary syndrome (PCOS), now officially renamed polyendocrine metabolic ovarian syndrome (PMOS), often causes irregular cycles and unpredictable bleeding
• Adenomyosis, where tissue similar to the uterine lining grows into the muscle wall
• Pregnancy-related causes, including ectopic pregnancy or miscarriage
• Cervical or uterine cancer, less common but important to exclude, particularly with persistent symptoms

Occasional spotting is usually not concerning, especially if you can identify a likely cause (such as starting new contraception or mid-cycle ovulation). However, you should seek medical advice if:

• Bleeding between periods is new or unusual for you
• It happens repeatedly over several cycles
• The bleeding is heavy or prolonged
• You experience bleeding after sex
• You have other symptoms like pain, unusual discharge, or fever
• You're postmenopausal and experience any vaginal bleeding
• You might be pregnant

Your doctor will typically:

• Take a detailed history, including your menstrual pattern, contraception use, sexual history, and other symptoms
• Perform a physical examination, including a pelvic examination if appropriate
• Arrange tests, which may include:
  • Pregnancy test
  • STI screening
  • Cervical screening (Pap smear) if due
  • Pelvic ultrasound to examine the uterus and ovaries
  • Blood tests to check hormone levels and thyroid function

Further investigations like hysteroscopy (examining inside the uterus with a camera) may be recommended in some cases.

The bleeding itself doesn't affect fertility, but some underlying causes can. For example:

• Polyps or fibroids may affect implantation
• Endometriosis can impact fertility
• Untreated STIs can lead to pelvic inflammatory disease and tubal damage
• Hormonal imbalances may affect ovulation

If you're trying to conceive and experiencing irregular bleeding, it's worth having an assessment to ensure any contributing conditions are identified and managed.

Treatment depends on the cause:

• Hormonal contraceptives, adjusting or changing your contraceptive method may help
• Antibiotics, for infections like chlamydia
• Polyp or fibroid removal, minor procedures to remove growths
• Hormonal treatments, to regulate cycles or treat conditions like PCOS
• Surgery, for more significant conditions like large fibroids or endometriosis
• Watchful waiting, if no concerning cause is found and symptoms are mild

Bleeding after sex (postcoital bleeding) can overlap with intermenstrual bleeding but deserves specific attention. While it can be caused by minor issues like cervical ectropion or vaginal dryness, it can also indicate cervical changes that should be assessed. If you experience bleeding after sex, especially if it's persistent, you should see a doctor for evaluation.