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Late Period: Everything You Need to Know

Having a late period might come as a surprise to you, especially if you’re not trying to get pregnant. Is it the time to take a test? Not so fast. The truth is, there are many reasons for late periods other than pregnancy. It can be affected by your health, age, diet, stress and even exercise. In this article, let’s look at the most common late period causes and figure out the correct approach to delayed menstruation.

My period is late: is there any reason to be worried?

Numerous studies show that a slight variation in the length of the menstrual cycle is normal.

More than 100 women with normal menstrual cycle lengths (between 21 and 35 days) took part in a large-scale study which showed interesting results: intracycle variability of greater than 7 days was observed in 42.5% of women! As you can see, one or a couple of days is not a problem

Late period under 16

For many teenagers, the first few years of menstruation involve irregular periods.

The body continually develops in this stage of life and a teen’s ovaries do not always release an egg monthly. This may result in periods as frequent as every two weeks or as far apart as three months.

Having fluctuating periods for two years or less during adolescence with normal physical exam results probably indicates a normal irregularity. Teens' cycles start to regulate as their hormone levels stabilize, although some women will still have irregular cycles on an ongoing basis.

Don't worry! Continue monitoring your body. When your period comes, use Flo to log the date and the symptoms. The app can be your late period calculator even if you have irregular cycle

late period pregnancy test

Is late period a reason to take a pregnancy test?

There’s a ton of reasons for late period besides pregnancy. When a woman stops having periods, it could be related to lifestyle factors like stress, strict diet, or extensive physical activity.

It might also result from the use of birth control pills, various diseases and hormonal abnormalities, or problems with the reproductive organs or the glands that regulate hormone levels. Finally, it could be due to pregnancy.

Home pregnancy tests enable you to determine if you're pregnant at a very early stage.

These tests detect the presence of the “pregnancy hormone” called human chorionic gonadotropin (hCG) in your urine. Your body makes this hormone when a fertilized egg is implanted in your uterus.

Is your period 5 days late or more? Take the test for the most accurate results. In some cases, a positive test may be seen earlier as hCG levels increase differently for different women. At the same time, late period negative pregnancy test is also quite common, so a delay doesn’t always indicate pregnancy.

Reasons for late period: what might they be?

If you have your period 3 days late, it doesn’t necessarily mean pregnancy. Late period reasons can be divided into 3 groups:

  • Physiological: stress, sudden weight changes, climate or time zone changes, breastfeeding (lactational amenorrhea), etc.
  • Medically induced: The cycle disruption is associated with taking or canceling medications, including hormonal contraceptives and antidepressants.​
  • Pathological: The cycle disruption is caused by diseases such as ovarian pathology, uterine diseases, endocrine system disorders, etc.
late period causes

Low body weight

Excessively low body weight — weight that is about 10% below normal — interrupts many hormonal functions in your body, which can cause ovulation and menstruation to stop.

Women who have an eating disorder, such as anorexia or bulimia often have reasons for delayed period because of these abnormal hormonal changes.


Doing activities that require rigorous training, combined with other factors, such as low body fat, stress, and high energy expenditure may disrupt a woman’s menstrual cycle. Don’t forget to add workouts and other physical activity in Flo, it will make the prediction of your late menstrual cycle and ovulation more accurate. 

Important to remember: If menstruation doesn’t come 7–10 days after the expected time, you should consult a doctor and be examined.







Flo Period & Ovulation Tracker

4.8, 279.7K Ratings
  • Amazing! Ricecake2003
    This app is super useful for tracking periods, and has given me mostly accurate predictions so far! I especially love that you can comment anonymously on posts and get help from and give help to the community.
  • Such an intuitive app! Hannah Malone
    I've tried several period tracker apps on the market and nothing is as good as Flo. It's accurate, detailed providing you with an abundance of parameters to log, and they even provide useful articles and surveys to help you better understand the complex nature of the female body.

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