My period is late: is there any reason to be worried?
It's the question many of us have wanted to know the answer to at some point or another: How late can a period be without being pregnant? If you're someone who uses a period calculator to predict their next bleed, and you're not actively trying to get pregnant, it's safe to say it can be... alarming if it doesn't turn up on time.
But it might comfort you to know that numerous studies show that a slight variation in the length of your menstrual cycle is normal. More than 100 women with average menstrual cycle lengths (between 21 and 35 days) took part in a large-scale study that showed interesting results: cycle variability of more than seven days was observed in 42.5 percent of the participants! As you can see, a one to two-day variation is very common.
Another large study conducted by Flo and the University of Adelaide showed that only about 16 percent of the participants had a 28-day cycle, even though you might have been told this was the typical length for menstrual cycles.