Common Reasons for a Late Period
woman sitting holding her head

If you've ruled out pregnancy and still have questions about a missed period, don't worry unnecessarily. There could be several reasons why you're late.


To the uninformed, a missed period can only mean one thing: You're pregnant. But in reality, there are numerous reasons why your period might be late -- or missing altogether.

The 28-day menstrual cycle is closely tied to your overall well-being. And when your body is out of balance, it can adversely affect the timing of your period.

The medical term for absent menstruation is called "amenorrhea." Primary amenorrhea refers to late onset of menstruation, or not having started menstruation by the age of 16. However, the condition is quite rare, affecting less than 1 percent of girls in the United States.

Secondary amenorrhea refers to a situation where menstruation begins at the appropriate age, but later stops for more than three cycles or six months. Affecting roughly 4 percent of the general female population, secondary amenorrhea is more common, and can be caused by a host of factors.

Most of those components center on hormonal shifts caused by heightened stress -- whether physical, mental or emotional -- which in turn can prevent ovulation, the precursor of menstruation (ovulation occurs roughly 14 to 16 days before women have their period). The female reproductive system is incredibly efficient, yet remarkably complex. As a result, it's vulnerable to outside factors -- both subtle and overt -- that can interrupt your body's equilibrium.

Of course, if there's a chance that you might actually be pregnant, rule out that possibility first. Home pregnancy tests are fast, inexpensive and 97 percent accurate when the directions are followed [source: American Pregnancy Association]. If the test is negative, check with your doctor, but also consider one of the following five possibilities.

Next, we'll examine the role of stress.