For many women, the amount of blood lost during a period is deeply personal, and can even be distressing. However, because flow, timing, and symptoms of periods can vary widely, many women may mistakenly believe that a heavy monthly bleed is simply a variation of normal. So how can you know whether your period is heavier than it should be? In this article, we’ll discuss what heavy menstrual bleeding is and the lifestyle factors and medications that can contribute to heavy bleeding. In a separate forthcoming article, we’ll discuss the common medical conditions that lead to HMB, how it’s diagnosed, and how to seek root-cause treatment for heavy periods.
Heavy menstrual bleeding may be common, but that doesn’t mean it’s normal
Indeed, while sangrado menstrual abundante (HMB) is not normal, it is quite common: an estimated 30% of reproductive-aged women report experiencing HMB, and some questionnaire-based surveys suggest prevalence rates of over 50% among women of reproductive age [1]. HMB remains one of the most common reasons women seek gynecologic care. Despite how common the experience of HMB is, there is no single cause, and even the definition of what constitutes a “heavy” period has evolved over time.
Defining heavy menstrual bleeding (HMB)
Historically, menstrual bleeding was considered “heavy” if blood loss exceeded 80 milliliters per cycle [2]—about 16 fully soaked tampons. The medical term menorrhagia refers to cyclical heavy bleeding over consecutive cycles. This quantity-based definition proved limited, as many women experience bleeding within the “normal” range that nonetheless disrupts daily life. Measuring blood loss also presents practical challenges (although copas menstruales can make it easier to track the quantity of blood lost).
Today, HMB is definido as excessive menstrual blood loss that interferes with a woman’s physical, social, emotional, or material quality of life [3].
Symptoms of HMB may incluir soaking through a pad or tampon every hour for several hours, doubling up on menstrual products, waking at night to change sanitary products, bleeding for more than seven days, passing clots larger than a quarter, fatigue or shortness of breath from blood loss, and needing to limit daily activities.
Symptoms of HMB may include soaking through a pad or tampon every hour for several hours, doubling up on menstrual products, waking at night to change sanitary products, bleeding for more than seven days, passing clots larger than a quarter, fatigue or shortness of breath from blood loss, and needing to limit daily activities.
What we didn’t know about heavy menstrual bleeding before
In 2007, guidance issued by the United Kingdom’s National Institute for Health and Clinical Excellence (NICE) recognized the historic overuse of hysterectomy for HMB. According to a January 2007 article published in the British Medical Journal (BMJ), “Mary Ann Lumsden, professor of gynaecology and medical education at the University of Glasgow and chairwoman of the guideline development group, said, ‘In the early 1990s it was estimated that at least 60% of women presenting with heavy menstrual bleeding would have a hysterectomy to treat the problem, often as a first treatment and without discussion of any alternative options. It is fundamental that all women with heavy periods know there is now a range of treatment options and [that] many don’t require surgery.’” [4]
As research has continued over the last few decades, we now understand more about the diverse causes of HMB, and—fortunately—hysterectomy is no longer the default treatment. Yet, many women still go years without a clear diagnosis, or are offered symptom-suppressing solutions, such as anticonceptivos hormonales or surgery, without investigation into the root cause.
What we know about heavy menstrual bleeding now
The menstrual cycle depends on the interplay of estrógeno y progesterona: estrogen builds the uterine lining, while progesterone stabilizes it. When hormone levels become imbalanced—more specifically, when estrogen levels are elevated relative to progesterone (often referred to as dominancia de estrógenos)—the endometrial lining may become excessively thick, leading to heavier shedding.
Various lifestyle issues may contribute to the hormonal imbalances that often cause or contribute to heavy menstrual bleeding.
Stress, poor diet, and endocrine disruptors
Hormonal imbalance can be driven por estrés crónico (which suppresses ovulation and progesterone), nutrient deficiencies, resistencia a la insulina (as in PCOS), excess body fat, alteradores endocrinos, and impaired estrogen detoxification due to liver or gut dysfunction.
Obesidad
Obesity also plays a notable role in estrogen dominance. Fat tissue contains aromatase, an enzyme that converts adrenal androgens into estrone—a potent form of estrogen—which can promote endometrial overgrowth and heavier bleeding. Obesity is also linked with higher levels of circulating free testosterone, which can result in ovulatory dysfunction, specifically extending the proliferative phase of the menstrual cycle in which the uterine lining is built, which can plomo to heavier bleeds [5].
Gut health
Previous Natural Womanhood articles have delved into emerging research that continues to identify the connection between gut and hormonal health, including how imbalances in the gut can lead to insulin resistance and inflammation.
Research has also shown the gut–brain–estrogen connection: the gut microbiome produces enzymes that influence the amount of active estrogen circulating in the body. Too little or too much of certain bacterial strains may also affect menstrual cycles. For example, one recent study pointed out that elevated levels of Escherichia/Shigella have been found in women with PCOS, endometriosis, and chronic endometritis—conditions frequently vinculado to heavier menstrual bleeding [6].
HMB, hormonal contraception, and other medications
While often prescribed to manage the symptoms of menstrual disorders, hormonal contraceptives and devices can sometimes worsen heavy or irregular bleeding.
- Copper IUDs are a well-documented cause of increased—or even continuous—bleeding. A 2010 review found that heavier bleeding and pain led up to 15% of users to remove the device within the first year, and another study reported that 67% experienced menstrual side effects. The likely cause is disruption of normal endometrial development and uterine muscle contractility [7].
- Progestin-only methods such as the mini-Pill or over-the-counter Opilly el Inyección anticonceptiva Depo-Provera, can also cause issues with bleeding. In one Estudio 2020 of 101 Depo-Provera users, 32.7 discontinued use, 24.2% of which was due to irregular bleeding [8].
- Tamoxifen, a drug used for the treatment of hormone-sensitive breast cancer, can have estrogen-like effects on the uterine lining, sometimes triggering menorrhagia. Abnormal uterine bleeding may ocurren in more than 50% of premenopausal women taking tamoxifen [9].
Seeking root-cause solutions for heavy menstrual bleeding
Of course, lifestyle and medication or only one possible cause of heavy menstrual bleeding. For many, HMB is linked to underlying medical conditions that can be diagnosed and treated with the help of a restorative reproductive medicine (RRM) trained healthcare practitioner. In a forthcoming article, we’ll discuss both the structural and non-structural underlying medical conditions linked to HMB.
