Perimenopause and Heavy Periods: Why Flooding Happens and How to Cope
Heavy flooding periods are common in perimenopause but they are not something you have to just endure. Learn why they happen and what you can do about them.
Why Periods Get Heavier in Perimenopause
Heavy periods in perimenopause catch many women off guard. After years of predictable flow, suddenly bleeding through a pad in under an hour or passing large clots can feel alarming. The cause is hormonal, specifically a condition called estrogen dominance that can occur during perimenopause. When you do not ovulate in a given cycle, your body produces little or no progesterone that month. Estrogen, however, continues to be produced. Without progesterone to balance it, estrogen causes the lining of the uterus to thicken beyond the usual amount. When that thickened lining finally sheds, the result is a much heavier period than normal. This cycle of anovulatory (no ovulation) months followed by heavy bleeding is one of the most common patterns in early to mid perimenopause.
What Is Flooding and How Heavy Is Too Heavy
The term flooding refers to a very heavy menstrual flow, sometimes coming on suddenly and intensely. Some women describe standing up and immediately soaking through clothing, or waking at night to find they have bled heavily despite using overnight protection. Medically speaking, heavy menstrual bleeding (menorrhagia) is defined as losing more than 80ml of blood per period, though most women cannot measure that directly. Practical signs of flooding include soaking through a pad or tampon in an hour or less for several hours in a row, needing to use both a pad and a tampon simultaneously, passing clots larger than a 50-cent coin, or having periods that last more than seven days. If this describes your experience, it is important to speak with your doctor, not only to find relief but because ongoing heavy bleeding can lead to iron-deficiency anaemia.
Could It Be Something Other Than Perimenopause
Heavy bleeding in your 40s is often perimenopause-related, but it is not always. Fibroids are benign growths in or on the uterus that become more common in the years before menopause, and they are a major cause of heavy and prolonged bleeding. Adenomyosis, a condition where the lining of the uterus grows into the muscle wall, causes heavy, crampy periods and becomes more symptomatic with age. Endometrial polyps, which are small growths on the lining of the uterus, can cause heavy or irregular bleeding. Thyroid problems and clotting disorders can also contribute. For these reasons, new or dramatically worsened heavy bleeding should always be investigated with an ultrasound or other assessment, not simply attributed to perimenopause and left untreated.
Medical Treatments That Can Help
There are effective medical treatments for heavy perimenopausal periods, and you do not have to white-knuckle your way through them. The levonorgestrel IUD (sold under brand names like Mirena) is one of the most effective options. It releases a small amount of progestogen directly into the uterus, which thins the lining and dramatically reduces or even eliminates bleeding in most users. It can stay in place for up to five to eight years depending on your age and which device you use, and it provides contraception too. Tranexamic acid is a non-hormonal tablet you take during your period to reduce blood loss significantly. Norethisterone and other oral progestogens can be used to delay or lighten periods. For women who have completed their family and for whom other treatments have not worked, endometrial ablation is a minor procedure that removes the uterine lining and significantly reduces or stops periods. Talk to your GP about which of these is right for your situation.
Managing Heavy Periods Day to Day
While you are working through treatment options or waiting for an appointment, there are practical things that can make heavy periods more manageable. High-absorbency menstrual products have improved significantly in recent years. Period underwear, menstrual discs, and high-capacity menstrual cups can handle heavier flow than traditional products and may give you more confidence to go about your day. Keeping a change of clothes at work or in your car removes some of the anxiety around unexpected flooding. Dark clothing on heavy days is not a long-term solution, but it can reduce stress in the short term. Eating iron-rich foods, including red meat, lentils, spinach, and fortified cereals, can help compensate for blood loss if your periods are consistently heavy, and it is worth asking your doctor to check your iron levels if you are feeling unusually fatigued.
Tracking Flow to Support Your Care
One of the most useful things you can do before a doctor's appointment about heavy periods is bring a clear picture of your flow. Many women underestimate how heavy their periods are when asked to describe them verbally. Logging your period in detail, including how many pads or tampons you use per day, whether you are passing clots, whether you are doubling up on products, and how long heavy flow lasts, creates a record that a doctor can actually use. PeriPlan lets you log symptoms day by day so that over time you have a real picture of your cycle and how it is changing. Showing up to an appointment with two months of logged data is far more useful than saying 'it has been quite heavy lately.'
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