Irregular Periods: Potential Causes and What to Do About It

You’ve probably heard that the average, or “normal”, menstrual cycle lasts 28 days. But we are all different and so are our periods. In reality, a normal cycle can be anything between 21 to 35 days. But how do you know if your period is irregular? What are the potential reasons behind irregular periods and what could it mean for your fertility? Keep reading for all the answers!

In this article you’ll find:

• Background on the menstrual cycle
• What is considered an irregular period?
• What causes irregular menstrual cycles?
• What do irregular periods mean for your fertility?
• Treatment for irregular periods

Background on the menstrual cycle

Each month, the female body goes through a hormonal process to prepare for possible pregnancy. During your cycle, rising estrogen and progesterone build up the uterine lining to allow for implantation of a fertilized egg. If you don’t get pregnant, the day you start bleeding marks the first day of a new cycle. Menstrual blood is made up of blood and tissue from the uterus as it sheds the lining. 

Some women have cycles that work like clockwork, and can pinpoint the day their period will start. But it’s totally normal for the cycle to fluctuate a bit (by a few days) from month to month too. 

The cycle also usually changes with age: many adolescent girls have heavier periods which get lighter in their 20s and 30s. As the body starts transitioning into menopause, it’s normal for the cycle to become irregular. Periods may become lighter or heavier than normal, bleeding may last for fewer or more days, or there may be no bleeding at all for one month or more and then it may start again. 

That being said, there are also several medical reasons for periods to become irregular, which may need to be treated by a doctor. It’s a good idea to keep track of your cycle using an app or simply on your calendar to have an understanding of your cycle length and know what’s normal or not for you.

What is considered an irregular period?

The American College of Obstetricians and Gynecologists states that an irregular cycle means that there’s a big change in the number of days between your periods from one month to the next. For instance, if one cycle is 25 days and the next cycle is 34 days, this is considered irregular. Missing one or more periods is a condition called amenorrhea.

Knowing what’s normal for you is helpful to find out if your periods are irregular. Other signs of an abnormal cycle include:

• Bleeding more frequently than every 21 days or less frequently than every 35 days
• Menstrual flow suddenly becomes much heavier or lighter than usual
• Vaginal bleeding or spotting in between periods
• Bleeding after sex
• Very heavy or painful periods accompanied by cramping, nausea, or vomiting
• Bleeding for more than 7 days

If you notice a change in your usual cycle or the above signs of irregular periods, see your gynecologist for a check-up. During your visit, tell them about your periods and any other symptoms you’re experiencing.

What causes irregular menstrual cycles?

There are many potential reasons for irregular periods. These are examples of what can cause your menstrual cycle to become irregular:

• Lifestyle factors: Gaining or losing a lot of weight, overly exercising, eating disorders (anorexia, bulimia or binge eating), travel, illness, or high stress levels over time can all disrupt your body’s hormones and interfere with your periods.

• Hormonal contraception: The birth control pill and hormonal IUD can make periods lighter, cause spotting in between periods, or stop you from bleeding entirely. If your cycle doesn’t return to normal after 6 months of stopping hormonal contraception, you should see your doctor as this could signal a hormonal imbalance or other health condition.

• Medication: Some medicines, such as those used to treat epilepsy or anxiety, can cause irregular periods.

• High amounts of prolactin: The hormone prolactin makes women produce breast milk after childbirth, so it’s normal to have irregular periods while breastfeeding. When the body produces too much of it when not breastfeeding, it’s called hyperprolactinemia, and can stop ovulation and periods altogether.

• Polycystic ovary syndrome (PCOS): This is a common condition that causes an imbalance of reproductive hormones and interferes with the menstrual cycle. Other symptoms of PCOS include excess body hair or baldness, acne, and weight gain. 

• Thyroid disorders: An overactive or underactive thyroid gland interferes with the body’s hormones and can disrupt the cycle.

• Pelvic inflammatory disease (PID): This is an infection of the reproductive organs usually caused by a sexually transmitted infection such as chlamydia.

• Bleeding disorders: These can contribute to heavy, irregular periods and cause women to pass blood clots while menstruating.

• Uncontrolled diabetes: Both type 1 and type 2 diabetes can contribute to irregular cycles. Taking medication can make periods normal again.

• Uterine fibroids or polyps: Non-cancerous growths on the uterus may cause heavy bleeding and painful periods.

• Uterine adhesions: Severe scarring on the womb may lead to light, infrequent, or missed periods or pain during menstruation. Adhesions inside the uterus is a condition called Asherman syndrome.

• Endometriosis: This condition causes tissue like the uterine lining to grow on other pelvic organs and can lead to very heavy, painful periods and pain during sex.

• Primary ovarian insufficiency (POI): This refers to when the ovaries stop working as they should before a woman reaches the age of 40, causing her to go into menopause prematurely.

What do irregular periods mean for your fertility?

Many of the reasons for irregular periods can also make it more difficult to conceive and have a successful pregnancy. For example, around 1 in 3 cases of irregular periods are due to PCOS, which is also the most common cause for female fertility struggles. 

If your period is irregular and you are struggling to conceive, you should see a doctor to find out what the cause may be. At LEVY Health, we offer a comprehensive fertility analysis reviewed by reproductive physicians from the comfort of your home. Test your fertility using the LEVY Fertility Code to learn more about your fertility.