What Causes Watery, Liquid Period Blood? Understanding Normal vs. Abnormal Flow

Understanding the Menstrual Cycle

The menstrual cycle is the monthly hormonal and physiological cycle a woman's body goes through to prepare for potential pregnancy. On average, a woman's cycle lasts about 28 days. Day 1 marks the first day of menstrual bleeding.

This bleeding, also called a "period," signifies that ovulation did not occur and the uterus is shedding its lining. The blood and tissues flow out of the body through the vagina. A period usually lasts between 3-7 days.

Though composition varies, normal menstrual fluid contains blood, cervical mucus, vaginal secretions, and endometrial tissue. The blood comes from the shedding uterine lining and is made up of water, proteins, and chemical substances like prostaglandins and thromboxane.

What Causes Liquid, Watery Periods?

Menstrual flow can range from thick and dark to liquidy and bright red. Seeking medical advice is wise if this represents a drastic change from your normal periods. However, some liquidity is common and not necessarily a major concern. Potential causes include:

High Prostaglandin Levels

Prostaglandins are hormones produced in the uterus that cause muscle contractions. Higher amounts can make menstrual blood thinner and more watery.

Low Progesterone

Progesterone helps thicken the uterine lining. Low levels can result in a thinner, more liquid-like lining being shed.

Blood Thinning Medications

Anticoagulant and antiplatelet medications like ibuprofen, aspirin, heparin, or warfarin can contribute to lighter, more liquid blood flow.

Copper IUD

Intrauterine devices (IUDs) like the ParaGard IUD release prostaglandins that thin uterine lining and dilute menstrual fluid.

Polyps or Fibroids

Noncancerous growths in the uterus can sometimes cause longer, heavier periods with a more watery composition.

Adenomyosis

This condition causes the uterine lining to break through the uterine wall muscle, leading to excessively heavy, thin periods.

Perimenopause

Hormonal fluctuations in the years leading up to menopause often cause irregular, heavy, watery periods.

Blood Vessel Abnormalities

Fragile blood vessels in the uterus may bleed excessively during menstruation, resulting in a runny texture.

Pregnancy Complications

In some cases, liquidy discharge could indicate issues like a threatened miscarriage, ectopic pregnancy, or placental abruption.

When to See a Doctor

Schedule an appointment with your OB/GYN if you notice any of the following accompanied by liquid periods:

• Bleeding longer than 7 days
• Changing pad or tampon more than once an hour
• Passing blood clots larger than a quarter
• Severe cramping or pain during periods
• Sudden onset of liquid periods
• Bleeding between periods
• Feeling dizzy, fatigued or short of breath

Seek prompt medical care if you experience:

• Fever or chills
• Foul-smelling discharge
• Severe lower abdominal pain
• Pregnancy symptoms accompanied by bleeding

Medical Evaluation of Liquid Menstrual Blood

To diagnose the cause of suddenly thin, watery periods, your doctor will likely:

• Ask about your medical history and any changes in menstrual patterns.
• Conduct a pelvic exam to visually assess the discharge.
• Order blood tests to check hormone levels.
• Perform an ultrasound to examine the reproductive organs.
• Do a biopsy of the uterine lining to test for abnormalities.

If an underlying condition like hypothyroidism, STI, or vitamin deficiency is suspected, additional testing may be needed.

Treating Excessively Liquid Periods

Treatment will depend on the underlying cause. Your doctor may recommend:

• Hormonal birth control pills or the levonorgestrel IUD to regulate menstrual flow.
• Iron supplements if excess bleeding causes anemia.
• Medications to control heavy bleeding like tranexamic acid or NSAIDs.
• Surgery to remove uterine polyps, fibroids or scar tissue.
• Treating any infection or thyroid issues.
• A hysterectomy if other options are ineffective.

When Liquid Periods Are Normal

Menstrual flow often changes consistency throughout your period and from cycle to cycle. Increased liquidity is usually only a concern if it represents a drastic change for you.

Normally, flow is heavier and more watery at the start of your period when the thickest part of the uterine lining is shedding. It then becomes a bit thicker and darker as your period tapers off. Subtle variations are also common:

• Younger girls may have lighter, more liquid periods after first starting menstruation.
• Flow may be thinner with anovulatory cycles where no egg is released.
• Illnesses, stressors, travel or sleep changes can temporarily alter period consistency.
• Flow often becomes more dilute and irregular perimenopause.

Managing Heavy, Watery Periods

If your doctor determines your liquid periods are within the range of normal, here are some tips to manage symptoms:

Use Extra Absorbency Tampons or Pads

Change them more frequently on heavy days. Try overnight pads, period underwear or a menstrual cup to avoid leaks.

Take Anti-Inflammatories

Over-the-counter NSAIDs like ibuprofen can reduce heavy bleeding as well as cramping.

Stay Well Hydrated

Drink extra fluids to prevent dehydration from heavy blood and fluid loss. Water, electrolyte drinks, broths and herbal teas help.

Monitor for Anemia

Heavy periods increase risk for low iron levels. Eat iron-rich foods and ask your doctor about supplements.

Slow Flow Naturally

Applying a cold pack can cause vasoconstriction to reduce blood flow. Avoid hot tubs, baths or anything that dilates blood vessels.

Consider Birth Control

Hormonal IUDs or low-dose birth control pills often lessen heavy bleeding while providing contraception.

Watch for Clots

Passing occasional small clots is normal, but see your doctor if they become larger than a quarter or very frequent.

When to Seek Emergency Care

Seek prompt emergency medical attention if you experience any of the following:

• Soaking over 2 pads per hour for multiple hours
• Lightheadedness, rapid heart rate, shortness of breath
• Severe abdominal pain that intensifies suddenly
• Fever over 100F (38C)
• Foul vaginal odor
• Vaginal bleeding during pregnancy

Excessive menstrual bleeding can quickly lead to dangerous blood loss. Call 911 or have someone drive you to an emergency room right away if your symptoms seem life-threatening.

The Takeaway

Temporary changes in your menstrual flow like increased liquidity or watery discharge are often harmless. However, see your doctor to identify the cause if it represents a concerning departure from your normal periods. Manage bothersome but normal liquid periods with pads, medication, hydration and natural remedies.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.