It’s a natural change of life, but the fact is menopause is still a mystery to many women going through it. Researchers too have only recently quantified how unpredictable menstruation patterns can be during perimenopause, the 2-10 years leading up to full menopause – which is usually defined as having been without a period for a full year. So what’s normal, and what should send you to your doctor?
Menstruation under scrutiny: The first long-term, multi-ethnic investigation into how women’s periods change as they approach menopause was published in 2014 in the BJOG: An International Journal of Obstetrics and Gynaecology. Conducted by researchers from the University of Michigan, University of California Los Angeles and elsewhere, the study examined 1,320 women for more than a decade.
Lead author and epidemiology professor at the University of Michigan’s School of Public Health Sioban Harlow tells me the area has been largely under-studied., with most of the existing data coming from research on younger women in the midst of their reproductive years.
“We know that the menstrual cycle changes across the lifespan,” Harlow explains. “Periods become most predictable for women in their 30s, then change most dramatically in the 5-8 years as you approach the transition into menopause. This can be a very startling shift from what you used to be able to predict quite easily – after decades of regular patterns – and we wanted to alleviate the anxiety women might feel if their changing periods are in fact quite normal and common.”
All between the ages of 45 and 54 at the start of the study in 1996, the subjects kept menstruation diaries chronicling how regular and heavy their periods were, as well as how long their periods lasted.
Prior to the study, Harlow says her team knew anecdotally that women tend to have heavier, irregular periods during this time frame.
But they were still surprised by the results.
“We found that more than three-quarters of women had three or more episodes of flow that lasted 10 or more days, with 91% having at least one of these prolonged periods during the transition to menopause,” Harlow explains. “The proportions were striking, and really show us how common longer bleeding episodes are.”
In addition, irregular periods were very common, as were prolonged episodes of spotting.
Over the decade-long study, more than 51,000 menstrual cycles were recorded by the participants. Here’s what the data revealed:
1. Prolonged periods (lasting 10 or more days):
- 91% of the 1320 women had at least one episode of a prolonged period
- 87% had two episodes of a prolonged period
- 77% had three episodes of a prolonged period
- Almost a third of the women who had prolonged periods had three such episodes within a 6-month window of time during their transition to menopause
2. Heavy periods (needing to change a sanitary product every 1-2 hours for more than 4 hours in a day):
- 34% of subjects had at least 3 episodes of three or more days of heavy bleeding
- 30% had at least 3 heavy periods early in their menopausal transition
- 34% had at least 3 such heavy periods late in their transition
- Almost 40% had 3 or more heavy periods within a 6-month window of time
3. Irregular (including spotting lasting 6 days or more):
- About 67% of women had at least three episodes of 6 or more days of spotting
- 51% had three or more spotting episodes early in their transition
- 75% had three or more spotting episodes late in their transition
- 23% recorded at least 3 of these episodes within a 6-month window of time
Ethnic differences: The subjects were Caucasian, African-American or of either Japanese or Chinese heritage living in either Michigan or California. African-American women were more likely to have heavy bleeds according to the results, but less likely to have a long period compared with the Caucasian subjects.
Harlow says these findings are consistent with other studies showing that fibroids in the uterus are more common in African-American women, which often lead to heavier menstrual periods.
When to see your doctor: Traditionally, according to Harlow, lengthy or heavy periods were a sign of abnormal bleeding, often prompting involved diagnostic tests like a uterine or endometrial biopsy. While her team discovered how common fluctuating and unpredictable periods can be, Harlow and her colleagues recommend seeking the advice of your health-care provider if you have 3 or more episodes within 6 months of heavy or prolonged bleeding, especially if they last more than two and a half weeks.
Since prolonged bleeding can increase the risk of anemia, which is a potentially dangerously low level of red blood cells in your system, it’s important to monitor periods that could lead to too much blood loss.
“Our results do show that 90% of women have at least one period that lasts 10 or more days,” she notes. “But it’s still very unusual to have a period last 15 days or more. If it happens once, it may very well not happen again; still, if you’re concerned at all, it’s best that you talk about it with your doctor.”
Bottom line: Overall, the study shows that bleeding heavily and having lengthy periods is very common in the many years approaching menopause. What women should remember is that they’re going from the most predictable phase to a highly-unpredictable time with respect to their periods. This data along with future research will help establish what is truly “normal” and common, and which patterns might indicate a more rare, but much more serious problem such as uterine cancer.
source: About Health