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- A typical menstruating individual typically gets their period every 21 to 35 days.
- But, late periods can also be a common occurrence and do not always indicate a pregnancy.
- There are many reasons your period could be late, including hormonal imbalances or a change in your exercise routine.
Delayed periods can be stressful and can sometimes lead sexually active individuals to believe they’re pregnant. But, a late period could be caused by many factors that aren’t related to pregnancy.
In some cases, a late period can be indicative of other underlying health conditions. Of course, if a late period is causing you concern, the best way to achieve peace of mind is by consulting your doctor.
Here are 12 reasons your period could be late.
You have polycystic ovary syndrome.
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When someone has polycystic ovary syndrome (PCOS), their egg sometimes doesn’t develop on schedule. This is because the condition causes hormone imbalances that directly impact the ovaries. As a result, ovulation and menstruation can be delayed.
Aside from irregular periods, other common indicators of PCOS include acne, thinning hair, and weight gain. The condition has no cure, but going on birth control can help regulate your period. It’s definitely worth checking with your doctor if you’re showing any combination of those symptoms.
You contracted pelvic inflammatory disease (PID).
Another condition that can severely affect your menstrual cycle is pelvic inflammatory disease (PID).
According to Mayo Clinic, PID occurs when bacteria makes its way into the vagina and cervix. Normally, it starts out as another sexually transmitted infection, like chlamydia or gonorrhea, that presents external symptoms. As the infection spreads to the cells of the uterus, it can lead to problems with menstruation.
The Office on Women’s Health lists irregular menstrual cycles (like late periods) as one of the symptoms of PID. There are other symptoms associated with it too, like pelvic pain, fever, and pain during sex.
If you suspect that PID is the reason for your abnormal menstruation patterns, it’s important to see a doctor. Untreated PID can lead to serious complications, like fallopian tube scarring and infertility.
Your new exercise regimen could be depleting hormone levels that make your period happen.
Even if you aren’t training overly strenuously, any change in exercise habits can cause changes in your period, according to a Harvard Study reported by the New York Times.
Strenuous exercise decreases the body’s estrogen levels and since estrogen is the primary hormone that triggers ovulation, a lack of it can slow down the entire menstrual cycle. Sometimes this can result in delays that last as long as several months.
Your weight has been fluctuating.
According to UC Riverside Health, both the ovaries and fat cells throughout the body produce estrogen. This means a sudden increase or decrease in weight can alter your period.
A 2012 study published in the Endocrinology and Metabolism Journal also found that irregular periods are more prevalent in individuals who suddenly gain or lose weight.
You recently started the keto diet or are currently following it.
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The strict low-carb keto diet can change how often your cycle occurs.
Registered nutritionist Vanessa Roster previously told INSIDER that the depletion of carbohydrates in the body can lower the body’s energy levels, which automatically affects the body’s ability to menstruate.
You’ve been getting less sleep than usual.
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Our bodies need sleep for a number of reasons, including regulating our temperature and ensuring our organs are functioning normally. Since the uterus itself is an organ, it should come as no surprise that a lack of sleep can negatively impact its ability to do its job.
In 2008, The American Academy of Sleep Medicine reported that individuals with sleep disorders, like delayed sleep syndrome, were highly likely to have irregular menstrual periods.
You used emergency contraception sometime in the past few months.
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If you’ve taken emergency contraception, like Plan B, as a precautionary measure after unprotected sex, there’s a chance it could be making your period very late. Princeton reported several studies that showed menstrual cycle lengths were altered after women took emergency contraception.
However, if your period is more than a week late and you recently took emergency contraception, The Center for Women’s Health suggests seeing your health care provider.
You’re experiencing early menopause.
One of the defining signs of menopause is the total disappearance of the menstrual cycle for more than 12 months. Most individuals who have a menstrual cycle anticipate they will experience this sometime during their late 40s or early 50s. But for some, it can happen earlier.
Perimenopause refers to the temporary stage right before full-blown menopause occurs. During this time, the ovaries start to produce less estrogen than normal, which causes you to get your period less often.
Even if you’re below the typical menopausal age, this is not something you should rule out entirely. The American Pregnancy Association says one out of every 1,000 women between age 15 and 29 will experience premature menopause.
In general, if your late period is accompanied by night sweats or vaginal dryness, you may want to ask your doctor about checking for perimenopause.
You’re very stressed.
Of course, worrying about your period can increase your stress levels and delay your period even more.
Healthline reports that breastfeeding is frequently associated with menstrual irregularities. This is mostly because breastfeeding stimulates prolactin production, a pituitary gland hormone that allows the body to create breast milk.
At the same time, prolactin is known to impede the menstrual process. This is because when it is being produced in the body, it keeps other hormones, like estrogen, raised. Elevated levels of hormones mean the body doesn’t experience that drop in levels it needs to trigger your menstrual cycle.
Generally, late periods related to breastfeeding are not a cause for concern, unless you’re experiencing other symptoms or you’ve recently given birth and had unprotected sex. Although many individuals purposely use breastfeeding as a tactic to delay ovulation (and therefore their periods), it doesn’t mean it’s impossible to get pregnant while breastfeeding.
There’s an issue with your thyroid.
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The thyroid is a small, butterfly-shaped gland located at the base of the neck and it has a lot of responsibilities. It’s mostly known for regulating the body’s metabolism and temperature, but when it is producing too few or too many hormones it can impact your menstrual cycle.
According to the Office on Women’s Health, hypothyroidism often causes menstrual irregularities, including both late and absent periods. A study from the late ’90s reported that hyperthyroidism, an overactive thyroid, can throw off your cycle, too.
You started a new birth control or haven’t been taking your birth control regularly.
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When it comes to birth control pills, most packs are divided into four weeks of seven-day doses. The first three weeks contain those stabilizing hormones, while the last week contains placebo pills.
If you haven’t gotten your period but just started a new pill pack, check to see if you’ve reached that fourth week yet. Your body may still be adjusting to the new level of hormones, which could be the reason why you’re late this month. Missing a few pills could also cause a delay in your menstrual cycle.
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