Menstrual Cycles 101 – Part 2: What’s a “normal” period?

Now that you’ve hopefully read the basics of Menstrual Cycles, part 1, I want to take the time to dive into common questions and issues surrounding periods. Concerns I frequently get from my patients and even friends are “My periods are too heavy” or “Why is my period lasting too long or happening more than twice per month?”

There are a few different answers to those questions, but let’s start with a quick recap from the basics article on what a “normal” cycle length is considered to be.

According to The American College of Obstetricians and Gynecologists, most ovulatory menstrual cycles last 21 to 35 days. The duration of actual blood flow generally lasts 5 days, with the heavier flow hitting in the first 3 days. This can vary by a few days and become longer or shorter – especially as women approach menopause. The amount of bleeding over the course of your period should be less than 80 milliliters. If you are like me, and am not well versed in the metric system, 80 milliliters is about one third of a cup. If you use pads or tampons (and not something like a menstrual cup), it may be hard to quantify this, but typically, you should not have to change your pad more frequently than every 2-4 hours.  

If your period doesn’t fall within the above time frame and it’s on the heavier side, there’s a few reasons why that can be. The most common reasons a period can be heavy involve normal or abnormal hormonal changes, or conditions like fibroids, polyps and adenomyosis.


Hormonal Changes:

When women first start having periods and as they begin to go through menopause, their menstrual cycles may be heavier or longer. These changes are the result of female hormones (estrogen and progesterone) being released at different levels than are needed to have a normal ovulatory menstrual cycle. This causes the unreliability in blood flow, length of bleeding, and frequency of periods.


Fibroids appear most commonly during childbearing years, and can range in size. These form in your uterus as noncancerous growths. You can have one fibroid or multiple, and often they are symptomless. It’s important to note that fibroids are not cancer but can rarely be associated with an increased risk of uterine cancer. Fibroids are very common, so common that I am someone who has suffered from them. They definitely contributed to some very heavy and painful periods in my past. 


Polyps can form due to overgrowth of cells in the uterine lining. These are also known as endometrial polyps. They’re growths attached to the inner wall of the uterus, and they are usually noncancerous. However, some can be cancerous or turn into cancer. 

Uterine polyps most commonly occur in women who are going through or have completed menopause, although younger women can get them, too. 


Adenomyosis occurs when endometrial tissue that should line the uterus grows into the muscular wall of the uterus. This tissue still follows normal menstrual cycle “protocol” in that it thickens, sheds and bleeds during your time of the month. Painful and heavy periods are a common result. 


So how do you know if you have any of these conditions? The first thing you should do is see your doctor to discuss further, and for an evaluation. These conditions can be detected through pelvic exams, ultrasounds and labs prescribed by your doctor. 

I know I just shared a ton of information with you, but don’t let this overwhelm you – there’s a number of treatments available for all of these conditions. 

I’ll get into each treatment option in later articles in more detail, but some to highlight include NSAIDS (Nonsteroidal anti-inflammatory drugs such as ibuprofen, naproxen), birth control pills, IUDS (intrauterine device), depo provera shots (contraceptive injection that contains the hormone progestin) or nexplanon (a tiny, invisible implant under the skin of a woman’s upper arm to provide birth control). 

Again, it’s really important you see your doctor to address any of your concerns, but If you have any questions or just want to connect, don’t hesitate to reach out!