Heavy Periods (Menorrhagia)

You may assume that a period is only medically heavy when a particular volume of blood has been measured. You may also believe that heavy bleeding is something you must tolerate during puberty, after childbirth or around perimenopause. Heavy menstrual bleeding is defined mainly by its effect on your physical, emotional, social and practical life. It can arise without a serious underlying condition, but it may also reflect anaemia, fibroids, adenomyosis, a bleeding disorder, medication effects or another condition requiring investigation.

Heavy menstrual bleeding is defined by its impact Heavy menstrual bleeding, often shortened to HMB, means menstrual blood loss that interferes with your quality of life. You do not need to collect or measure the blood. Clinicians are advised to focus on how bleeding affects you rather than relying only on an estimated volume. You may have heavy periods if you need to change a pad, tampon or menstrual product every one to two hours, need to use two products together, bleed through clothing or bedding, pass clots larger than about a 10 pence coin. Bleed for more than seven days, avoid work, school, exercise, travel or social activities, need to plan your day around access to toilets, or feel exhausted, dizzy or breathless during or after periods. The pattern matters, but so does what is normal for you. A clear increase from your previous periods deserves assessment even when another person might describe the same bleeding as manageable. Menorrhagia is an older term Menorrhagia traditionally describes very heavy or prolonged menstrual bleeding. Healthcare guidance increasingly uses heavy menstrual bleeding because it emphasises lived impact rather than requiring an exact blood volume threshold. The terms are often used interchangeably in clinical conversations. A heavy period is still menstrual bleeding Menstrual bleeding follows a cycle and occurs when you are not pregnant. Bleeding caused by pregnancy, miscarriage, ectopic pregnancy, bleeding between periods, bleeding after sex, or bleeding after menopause is assessed differently and should not be labelled simply as a heavy period. If pregnancy is possible and bleeding is unusual, take a pregnancy test and seek clinical advice according to the severity and accompanying symptoms. Early pregnancy complications can cause bleeding that resembles a period. Heavy bleeding can cause iron deficiency anaemia Repeated blood loss can reduce your red blood cells and iron stores. Possible symptoms include tiredness, reduced exercise tolerance, breathlessness, palpitations, headache, dizziness, pale skin, difficulty concentrating, restless legs, or craving non food substances such as ice. These symptoms are not specific to anaemia, but they increase the importance of a blood test. A full blood count is recommended for everyone presenting with heavy menstrual bleeding, alongside treatment rather than waiting for treatment to fail first. Heavy periods do not always have an identifiable structural cause Some people have heavy bleeding even though examination and imaging do not reveal a fibroid, polyp or other structural problem. Possible contributors include the way the womb lining regulates bleeding, hormonal contraception, irregular ovulation, perimenopause, medicines affecting clotting, or a bleeding disorder. Not finding a structural cause does not mean the symptom is insignificant. Treatment can still be offered. Fibroids can increase bleeding or pressure Fibroids are non cancerous growths arising from the muscle of the womb. Depending on their size and position, they may cause heavy periods, prolonged bleeding, pelvic pressure, abdominal enlargement, frequent urination, constipation, pain, or fertility difficulties. Fibroids growing beneath the womb lining can interfere with the womb's ability to control bleeding. A fibroid found on a scan is not automatically the cause. Its location, size, symptoms and effect on the womb cavity all matter when selecting treatment. Adenomyosis may cause heavy and painful periods Adenomyosis occurs when tissue similar to the womb lining is found within the womb muscle. Possible features include heavy bleeding, marked period pain, pelvic aching, a bulky or tender womb, or pain during sex. Transvaginal ultrasound is the preferred initial imaging test when heavy periods occur with significant period pain or examination suggests adenomyosis. Alternatives can be discussed when an internal scan is unsuitable or declined. Endometriosis may coexist with heavy bleeding Endometriosis more typically causes pain than heavy bleeding. Possible patterns include period pain that interrupts daily activities, chronic pelvic pain, pain during or after sex, pain when opening your bowels or urinating during a period, fertility difficulties, or fatigue. You can have endometriosis even when an ultrasound is normal. Clinicians are advised to suspect it from the symptom pattern, including in adolescents. Polyps may cause irregular as well as heavy bleeding A uterine or cervical polyp is a growth arising from the lining of the womb or cervix. Polyps may cause heavy periods, bleeding between periods, bleeding after sex, or irregular spotting. Most are non cancerous, but persistent bleeding may require hysteroscopy or another examination to identify the source. Irregular ovulation can produce unpredictable heavy bleeding When ovulation does not occur regularly, the womb lining may build up for longer and then shed unpredictably. Possible associated patterns include long gaps between periods, irregular cycles, heavy bleeding after a missed period, acne, increased facial or body hair, weight change, or difficulty becoming pregnant. Polycystic ovarian syndrome is one possible cause, but thyroid disease, stress, weight change, chronic illness and perimenopause can also affect ovulation. Perimenopause can change the bleeding pattern During perimenopause, periods may become closer together, further apart, heavier, lighter, or less predictable. These changes are common, but they should not automatically be attributed to menopause without considering pregnancy, anaemia, fibroids, endometrial problems and other causes. Bleeding after you have been without periods for 12 months is postmenopausal bleeding, not another period, and should always be assessed. Contraception and medicines can alter bleeding Different contraceptive methods affect periods differently. A copper intrauterine device can make bleeding heavier or more painful, particularly after insertion. Hormonal methods may cause lighter periods, no periods, irregular spotting, prolonged bleeding during adjustment, or unpredictable bleeding with some methods. Bleeding changes after starting contraception may be expected, but pregnancy, infection, incorrect device position and unrelated causes still need consideration when bleeding is severe, painful or persistent. Bleeding can be worsened by anticoagulants, aspirin, some antiplatelet medicines, certain hormonal treatments, or tamoxifen. Do not stop an anticoagulant or prescribed medicine without advice. The clinician must balance bleeding risk against the condition the medicine is treating. A bleeding disorder may first appear through periods An inherited bleeding disorder, such as von Willebrand disease, may cause heavy periods from the time periods first started, frequent nosebleeds, easy bruising, prolonged bleeding after dental work, excessive bleeding after surgery or childbirth, or relatives with similar problems. Considering clotting disorder testing is recommended when heavy bleeding has been present since periods began and there is a personal or family pattern suggesting abnormal bleeding. Particularly important in adolescents whose heavy bleeding begins with their first periods. Adolescents should not be told heavy bleeding is simply normal Cycles can be irregular during the first years after periods begin. However, very heavy or prolonged bleeding can cause substantial anaemia and may reveal a bleeding disorder. A young person needs prompt assessment if they soak through menstrual products rapidly, become dizzy or faint, look very pale, miss school repeatedly, bleed for prolonged periods, have easy bruising or nosebleeds, or may be pregnant. Questions about pregnancy and sexual activity should be asked privately and respectfully, without assumptions. Pregnancy must be considered A pregnancy test may be appropriate whenever pregnancy is biologically possible, even if contraception is being used, bleeding resembles a normal period, the person believes pregnancy is unlikely, or cycles have been irregular. Pregnancy related bleeding accompanied by one sided pelvic pain, shoulder tip pain, dizziness, faintness or collapse may indicate ectopic pregnancy and requires urgent or emergency assessment. Heavy bleeding after childbirth requires urgent assessment Bleeding is expected after birth, but sudden or very heavy bleeding can be a postpartum haemorrhage. Call 999 or seek emergency maternity assessment if bleeding after birth suddenly becomes very heavy, soaks products rapidly, contains large clots, is accompanied by faintness, racing heartbeat or breathlessness, occurs with severe abdominal pain, or makes you feel very unwell. Later postnatal bleeding with fever, worsening abdominal pain or offensive discharge may indicate infection and needs urgent maternity review. Postmenopausal bleeding is not a period Postmenopausal bleeding means any vaginal bleeding occurring after menopause. This includes a single spot, pink or brown discharge, bleeding after sex, a brief light bleed, or heavier bleeding. Most cases are not caused by cancer, but cancer must be excluded. GP assessment is advised even when the bleeding happens only once or is very slight. An urgent suspected cancer referral is recommended for unexplained postmenopausal bleeding that cannot be attributed to HRT. Assessment, testing and treatment Useful details for your clinician include: How often products need changing. Whether you use more than one product. Number and approximate size of clots. Duration of bleeding. Flooding through clothes or bedding. Bleeding between periods or after sex. Period pain. Pelvic pressure. Pain during sex. Pregnancy possibility. Contraception. Medicines. Personal or family bleeding pattern. Effect on work. Education. Sleep and relationships A menstrual diary can make the pattern easier to explain. A full blood count is usually required. Further tests depend on your history. Clinicians do not routinely need female hormone tests solely because bleeding is heavy, thyroid tests without symptoms suggesting thyroid disease, or a scan for every uncomplicated presentation. A pelvic ultrasound can assess fibroids, adenomyosis, ovaries, womb size and pelvic masses. A hysteroscopy uses a thin camera to inspect the inside of the womb and is recommended when what the person describes suggests polyps, submucosal fibroids or endometrial disease, particularly with persistent bleeding between periods or relevant risk factors. Treatment decisions should take account of how much the bleeding affects you, pain or pressure symptoms, test findings, other medical conditions, need for contraception. Whether pregnancy is desired now or later, medicine risks, whether you want to retain your womb, and previous treatment experience. You do not have to accept a treatment solely because it is usually offered first. A levonorgestrel releasing intrauterine system (LNG IUS) is recommended as a first consideration for many people with no identified structural cause, small fibroids not distorting the womb cavity, or suspected or confirmed adenomyosis. Bleeding can be irregular during the first months, and allowing about six cycles to assess the full benefit is advised when it remains acceptable to you. Other options include tranexamic acid, anti inflammatory medicines, combined hormonal contraception, cyclical oral progestogens, or progestogen only contraception, chosen according to your health, age, past or current smoking, migraine pattern, clotting risk, need for contraception and preferences. Specialist procedures may include removal of a polyp, removal of a submucosal fibroid, myomectomy, uterine artery embolisation, endometrial ablation, or hysterectomy. Some of which affect or permanently remove fertility, and these implications must be discussed before treatment.

Heavy menstrual bleeding is assessed through four connected questions: how much does the bleeding disrupt your life, is the blood loss affecting your circulation or causing anaemia, are there symptoms suggesting a structural, hormonal or bleeding related cause, and which treatment fits your priorities, health and plans for pregnancy. The goal is not merely to reduce a number it is to make bleeding manageable and protect your health.