Certain factors can affect your monthly cycle, including weight change and stress. If your period is a few days late, it typically is not a cause for concern. But a period that’s a few weeks late may indicate an underlying condition.
If you don’t have any known condition affecting your menstrual cycle, your period should start within 21 to 35 days of your last period, depending on your normal cycle.
Regular periods can vary. If your regular cycle is 28 days and you still have not had your period on day 29, your period is officially considered late. Likewise, if your regular cycle is 32 days and you still have not menstruated on day 33, this would be late for you.
Either of these two scenarios may technically be late, but should not be an immediate cause for concern. Variations in menses from month to month can occur due to various reasons.
After 6 weeks without bleeding, you can consider your late period a missed period.
Several things can delay your period, from basic lifestyle changes to chronic health conditions. Here’s a look at 10 potential culprits.
Your body’s stress-response system is rooted in a part of the brain called the hypothalamus. While you may no longer be running from predators, your body is still hardwired to react as if you were.
When your stress level peaks, your brain tells your endocrine system to flood your body with hormones that switch on your fight-or-flight mode. These hormones suppress functions, including those of your reproductive system, that are not essential to escaping an imminent threat.
If you’re under a lot of stress, your body can stay in fight-or-flight mode, which can make you temporarily stop ovulating. This lack of ovulation, in turn, can delay your period.
Severe changes in body weight can screw with your period’s timing. Extreme increases or decreases in body fat, for example, can lead to a hormonal imbalance that causes your period to come late or stop entirely.
In addition, severe calorie restriction affects the part of your brain that “talks” to your endocrine system and gives instructions for the creation of reproductive hormones. When this communication channel is disrupted, hormones can get out of whack.
A strenuous exercise regimen can also cause missed periods. This is most common in those who train for several hours a day. It happens because, whether intentionally or not, you’re burning way more calories than you’re taking in.
When you burn too many calories, your body doesn’t have enough energy to keep all its systems running. More strenuous workouts can increase hormone release that can affect your menstruation.
Periods typically go back to normal as soon as you lessen training intensity or increase your caloric intake.
Polycystic ovary syndrome (PCOS) is a set of symptoms caused by an imbalance of reproductive hormones. Many people with PCOS do not ovulate regularly.
As a result, your periods may:
- be lighter or heavier than standard periods
- arrive at inconsistent times
- disappear altogether
Other PCOS symptoms can include:
- excess or coarse facial and body hair
- acne on the face and body
- thinning hair
- weight gain or trouble losing weight
- dark patches of skin, often on the neck creases, groin, and underneath breasts
- skin tags in the armpits or neck
Many people love the pill because it makes their periods so regular. However, it can sometimes have the opposite effect, especially during the first few months of use.
Similarly, when you stop taking the pill, it can take a few months for your cycle to get back to normal. As your body returns to its baseline hormone levels, you may miss your period for a few months.
If you’re using another hormonal birth control method, such as an intrauterine device (IUD), implant, or shot, you might completely stop getting your period.
Perimenopause is the time leading up to your menopausal transition. It typically starts in your mid- to late 40s. Perimenopause can last for several years before your period stops completely.
For many, missed periods are the first sign of perimenopause. You may skip a period 1 month and be back on track for the following 3 months. Or, you may skip your period 3 months in a row and find that it arrives unexpectedly, often lighter or heavier than you’re used to.
Early menopause, also known as premature ovarian insufficiency, happens when your ovaries stop working before you turn 40.
When your ovaries are not working the way they should, they stop producing multiple hormones, including estrogen. As your estrogen levels drop to all-time lows, you will begin to experience the symptoms of menopause.
Late or missed periods may be an early sign. You may also experience:
Other signs of premature ovarian insufficiency include:
- vaginal dryness
- trouble getting pregnant
- decreased sexual desire
- mood disturbance or mood changes
Your thyroid is a butterfly-shaped gland in your neck that produces hormones that help regulate many activities in your body, including your menstrual cycle. There are several common thyroid conditions, including hypothyroidism and hyperthyroidism.
Both hypothyroidism and hyperthyroidism can affect your menstrual cycle and cause irregularity, but hyperthyroidism is more likely to cause late or missed periods. Sometimes, your period may disappear for several months.
Other symptoms of a thyroid issue include:
- heart palpitations
- appetite changes
- unexplained weight changes
- nervousness or anxiety
- slight hand tremors
- changes to your hair
- trouble sleeping
Certain chronic health problems, especially celiac disease and diabetes, are sometimes associated with menstrual irregularities.
Celiac disease is an autoimmune disease that affects your digestive system. When people with celiac disease eat gluten, their immune system reacts by attacking the lining of the small intestine.
When the small intestine is damaged, it impairs the body’s ability to absorb nutrients from food. This can lead to malnourishment, which affects normal hormone production and leads to missed periods and other menstrual irregularities.
Those with type 1 and type 2 diabetes might also experience a missed period in rare cases. This tends to only happen when blood sugar levels are not managed.
If there’s a chance you may be pregnant and your cycles are typically regular, it may be time to take a pregnancy test.
Try to do this about 1 week after your period was supposed to start. Taking a test too early can result in the test being negative even if you’re pregnant, as it’s too early for the test to pick up the pregnancy hormone in the urine.
If your periods are typically irregular, it can be harder to find the right time to take a pregnancy test. You may want to take a few tests over the course of several weeks, or talk with a healthcare professional to be sure.
Other early symptoms of pregnancy to watch for include:
- tender, painful breasts
- swollen breasts
- nausea or vomiting
Your period is generally considered late if it has not occurred within your cycle’s usual time frame since the start of your last period.
Many things can cause this to happen, from routine lifestyle changes to underlying medical conditions. If your period is regularly late, make an appointment with a healthcare professional to determine the cause.