A Moving Milestone

Why Are Periods Starting So Much Earlier These Days?

Everything parents need to know about the increase in early menarche.

by Arielle Tschinkel
A mother in a gray sweater talks to her daughter, who wears a mustard-colored top. They are engaged ...
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Navigating your child through puberty — including their first period — can feel overwhelming for any parent. And if you thought you had until the tween years to worry about it, think again, friend. According to new research, the average age for first periods is decreasing in the U.S., which means you'll want to begin having discussions with your little one far earlier than you may have planned.

The research, recently published in JAMA Network Open as part of the Apple Women's Health Study, confirmed that the average age of first menarche has decreased over the past five decades. But the new study shows that early menarche is more prevalent among Black, Hispanic, Asian, and mixed-race participants, as well as those who reported lower socioeconomic status.

Respondents were separated into brackets based on the decade in which they were born, between 1950 and 2005, self-reporting when they began menstruating and how long it took for their menstrual cycle to become regular. Among participants born between 1950-1969, the average age at menarche was 12.5 years, and the rates of early (younger than 11) and very early menarche (younger than 9) were 8.6% and 0.6%, respectively. Among participants born between 2000-2005, the average age of menarche was 11.9 years, and the rates of early and very early menarche were 15.5% and 1.4%, respectively.

But what does this all mean, and should parents be concerned? And what should parents do if they notice first-period signs before their kid hits double digits? Fear not, because two pros are here to help.

Why are periods starting earlier?

Turns out, this trend is nothing new, as Diane J. Snyder, MD, FACOG, tells Scary Mommy. Snyder, a pediatric and adolescent gynecologist with Advantia Health, notes that the average age of first menarche was 16 over a century ago, and it has slowly decreased ever since. Now, she says it's not unusual to see first periods around 11 or even earlier, especially among certain ethnic minorities and socioeconomic groups.

Experts aren't exactly sure what has caused the age to decrease, but there are several potential factors, as Jillian LoPiano, MD, MPH, FACOG, adds. LoPiano, an OB-GYN and the chief health officer at Wisp, notes that environmental endocrine disruptors — like air pollution — can contribute to hormonal changes.

"We know that girls need a certain percentage of body fat to initiate menstruation and a slightly higher percentage to maintain menstruation," says Snyder. "Body mass and body fat definitely play some role in the beginning of puberty," which she notes begins around two years before the onset of menstruation.

"One working hypothesis focuses on food deserts where lower-income communities lack access to healthy nutrition-dense foods," adds LoPiano.

Another possible factor? Exposure to stress in childhood. Childhood sexual abuse has been linked to early menarche among Black women in the U.S., along with parental conflict and/or family tension.

Together, it's a trifecta that disproportionately impacts low-income and/or non-white kids when compared to their counterparts, who might have more access to nutritious food, clean air, safe outdoor spaces, and lower levels of stress.

What are the potential impacts?

Even if you're prepared to support your child through puberty, offering a safe landing zone for them to ask questions and express their emotions, early puberty can have detrimental impacts on their mental and physical well-being, as both experts point out.

"If a child gets their period early (i.e., in elementary school), they will look older than an average elementary schooler because they will be taller and have breast development," says Snyder. "The challenge is with emotional maturation matching body maturation and the ramifications of that." Appearing older than one's age can impact how your child is treated, she adds, especially if friends and classmates have yet to go through puberty. This can contribute to feelings of loneliness or isolation in an already vulnerable phase of life.

"We also find that sometimes girls who mature earlier and have a period earlier tend to have a sexual debut earlier as well," says Snyder. "This is very challenging from every aspect of psychological and general health as well as the need for earlier pregnancy prevention."

There is also the risk of advanced bone age, Snyder explains, because once the ovaries start making estrogen, it causes the laying down of stronger bone, getting ahead of where you should be for your age. "This is why calcium intake and regular exercise are even more important during puberty," she says. "You get very tall early but can actually end up being short later due to the early closure of the bone growth plates."

Snyder also points out that "when you start your periods early, you tend to end your periods early. Then, when you're on the other side of life, you go through early menopause, which has ramifications on bone health and cardiovascular health down the road."

"Also, when you start your periods early, you tend to end your periods early," as Snyder points out. "Then when you're on the other end of life, you go through early menopause, which has ramifications on bone health and cardiovascular health down the road."

"Early menarche is associated with increased risk in cardiac disease as well as some reproductive cancers, including breast cancer," adds LoPiano.

What can parents do?

Both doctors recommend checking in with your child's doctor if you notice signs of puberty beginning between the ages of six and nine. Signs to look for, per Snyder: "a growth spurt with a rapid increase in height, followed by breast development, then pubic hair growth, and underarm hair growth. The first period usually occurs two to two and a half years after the growth spurt begins."

"When we see precocious puberty — a diagnosis of puberty before the age of eight — your pediatrician will do an assessment and provide a referral to a pediatric endocrinologist for diagnosis and treatment. Once early puberty starts, there are treatment options to delay puberty until the appropriate chronological age."

Aside from all the physical changes, your child might not even fully be aware of puberty and periods, which can feel scary and overwhelming. Arming yourself with knowledge is a great first step, says LoPiano. "Consulting with early childhood educators and pediatricians is always a good idea when talking with your child about complicated topics."

How can you talk to your child?

"As a mom, I speak with my children using anatomical language and age-appropriate explanations of bodily functions, and I always avoid shame-based language and approach," she adds. In fact, can the "cranky" talk, says Snyder. There's no such thing as gender-based bad moods, and she says it creates a problematic narrative around periods. "We all get cranky at other times than when we are having our periods. Boys get cranky," she points out.

Snyder also recommends openly showing your kids what your own period is like so they know that it's not scary, simply a normal bodily function. "Don't be afraid to show kids a menstrual pad or how to insert a tampon and that it doesn't hurt," she says, adding, "It is important for parents to understand normal puberty. Everyone goes through it differently and at different times. We see the same thing in menopause. It is a normal physiological function, but everyone transitions differently."

And yes, including all non-menstruating family members in the conversation is equally important. "Boys should be comfortable talking about periods," says Snyder. "It shouldn't be a secretive thing that you can only talk about with your mom. I think dads should be absolutely comfortable talking about menstruation with their daughters. The more you can normalize it, the more comfortable kids are with the whole process."

Snyder recommends the following "wonderful parent and patient resources" for additional support: