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How Late Can a Period Be Without Being Pregnant?

Some people have their period every 28 days like clockwork. But most people will experience a late or missed period at least once without being pregnant, and that’s perfectly normal.

Whether you regularly use a period calculator or you just intrinsically know when you're due on, for many, a late period can trigger thoughts of potential pregnancy. But it doesn’t necessarily mean that you’re pregnant.

How many days late can a period be before worrying about pregnancy?

Everyone’s cycle is different, but how late can a period be? Healthy cycles can range in length from 21 to 35 days, and how long a cycle lasts can vary from cycle to cycle. Unless you have irregular cycles due to a medical condition, you probably have at least a rough idea of when to expect your next period.

A period is considered late if it hasn’t started within seven days of when you expect it. Most pregnancy tests will be able to give you accurate results by the time your period is late. If you get a negative pregnancy test after missing a period, and your period is more than a week late, you may want to see your health care provider to figure out what’s going on. 

If you get a negative pregnancy test result, still haven’t gotten your period, and start to experience early pregnancy symptoms, consider taking another test. Sometimes, home pregnancy tests can give a false-negative result if it’s taken too early in the pregnancy to detect human chorionic gonadotropin (hCG) in your urine. In these cases, it can take a bit longer to know you’re pregnant after a late period. The earliest hCG detection can be done with an hCG serum test performed by a doctor as early as 8 to 10 days after ovulation.

What counts as a late period?
Discover answers to questions like these and on important topics like Irregular periods, early pregnancy symptoms and more.

How do you know if your period is late?

Whether you’re busy or just have a lot on your mind, it’s easy to forget when you should expect your period to start. But if you’re not sure when to expect your period, it’s hard to know if it’s late.

A period tracking app like Flo can help. By logging your usual menstrual cycle dates, Flo can predict when you can expect your period. This information can also be very useful if you need to go to your health care provider when you miss your period. Having information about your cycle can help them understand what’s happening inside your body.

Reasons for a late period (other than pregnancy)

There are lots of causes for a late period that aren’t pregnancy. Some of the most common causes of late periods include:

Hormonal birth control

One of the ways that hormonal birth control prevents pregnancy is by thinning the uterine lining. This lining, or endometrium, is where an embryo would implant itself if you got pregnant. It’s also the layer that sheds from your uterus during menstruation each month. Since birth control makes this layer thinner, many people experience lighter periods while they’re taking it. 

In some cases, the endometrium gets so thin that menstruation doesn’t happen. Everyone is different, and as long as you’ve been taking your birth control correctly, missing a period on birth control shouldn’t be a cause for concern. If it will ease your mind, you can always take a pregnancy test if you’re not sure.


Stress affects everyone differently. When you experience chronic or extreme stress, hormones like cortisol can interfere with your menstrual cycle. However, it’s hard to determine exactly how much stress you have to experience for this to occur, since everyone reacts to stress differently.

If you have an underlying health condition, stress could be an added factor that makes your cycles even more irregular. Creating healthy lifestyle habits can help keep both your mind and body in good shape.

A confused woman holding a menstrual calendar wondering how late a period can be without being pregnant

Weight fluctuations

Being overweight or underweight can cause hormonal imbalances since fatty tissue plays a role in synthesizing hormones. Additionally, gaining or losing a significant amount of weight in a short amount of time can affect your hypothalamus. The hypothalamus is part of one of your body’s systems responsible for hormones. If the function of your hypothalamus is disrupted from an abrupt weight change, it can disrupt ovulation and cause a late or missed period. 


Certain medications, such as certain antipsychotics, can create hormonal imbalances that can cause a late or missed period. Check with your health care provider or pharmacist about the possible side effects of any medications you’re taking.

Polycystic Ovary Syndrome 

Polycystic ovary syndrome (PCOS) is a condition that can cause irregular periods because it affects your ovulation. Other symptoms of PCOS include:

  • Excessive body hair growth (hirsutism)
  • Scalp hair loss
  • Weight gain or difficulty losing weight
  • Acne on the face, chest, and upper back
  • Difficulty getting pregnant
  • Darkening of skin, particularly along neck creases, in the groin, and underneath breasts

If you believe that you could have PCOS, a health care provider can give you a proper diagnosis and prescribe the treatment that you need.

There are other conditions that can cause late or missed periods other than pregnancy. These conditions include:

  • Perimenopause
  • Thyroid disease
  • Pituitary tumors
  • Breastfeeding
  • Change in sleep schedule
  • Dietary changes
  • Excessive exercise

Having a late period doesn’t always mean that you’re pregnant. In some cases, such as when you’re experiencing stress, your cycles could return to normal once you’re feeling better. However, if you’re worried about the underlying cause of your late period, it’s always helpful to take a pregnancy test and/or contact your health care provider if other symptoms arise.  

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