What to Know and When to Contact Your Doctor
A recent study published in JAMA Network Open caught my eye. The study, led by researchers at the Harvard T. H. Chan School of Public Health, was about trends related to the onset age of menstruation and period irregularities.
As a board-certified OB-GYN with fellowship training in pediatric and adolescent gynecology, I know the study captured the attention of many in the medical community and in the public. The results suggest that the average age of a girl’s first period is decreasing and how the average amount of time it takes for girls to have a regular menstrual cycle may be increasing.
I do believe the study had some shortcomings in its methodology – including relying on adult participants who first got their periods decades ago to recall details about the age of their first period – but the study does give me an opportunity to educate people about puberty in girls. Parents – and of course, young adolescents – often want to know what is considered normal puberty during a time that can often feel very turbulent. Parents also want guidance on when to reach out to a physician.
What Parents Should Know
Here is what I want parents/ guardians to know:
In general, puberty in girls starts with breast development.
The breast tissue will respond to the hormone estrogen by beginning to develop first. The average age for breast development is around age 10-11. Remember what “average” means: Some girls will start developing breasts younger than age 10-11, and some will develop breasts older than age 10-11.
The first period should never arrive as a complete and total surprise; about a year and a half to two years after breast buds appear, girls usually get their first period. The average age of a first period is age 12.5.
We know that compared with decades ago, breast development is starting in some girls at younger ages.
This has been well known, but not necessarily well understood. We think many possible reasons exist. The rising rates of childhood obesity certainly can play a role, as knowing the start of breast development can be more difficult among children with obesity. We also worry about a potential link between obesity, earlier puberty and later development of polycystic ovarian syndrome (PCOS), a common condition with long-term fertility and health implications.
We also know that some children have certain environmental exposures also may develop breasts at a younger age.
We know that exposures to environmental chemicals (what we refer to as “endocrine disruptors”) can mimic the hormone estrogen inside the body. For example, regular exposure to tea tree oil and lavender oil can cause early breast development.
Exposure to hormonal medications, especially in the form of creams, can also be a factor in causing early puberty.
I have had patients whose parents use creams containing estrogen. When parents apply the cream to themselves, it is important to take care to wash their hands thoroughly and cover the parts of the body to which they applied the creams. If estrogen comes into contact with their kids repetitively, then the exposure can accumulate over time and cause breast development. Adults should also keep birth control pills – which often contain estrogen – away from children.
Early puberty – also called precocious puberty – is a concern because girls usually stop growing shortly after getting their period.
Although these children may initially be tall for their age, their growth levels off and they are often shorter than their peers who enter puberty at a more typical time. They may never reach their most maximal adult height. This is why children with precocious puberty are treated with puberty blockers.
Precocious puberty also is a concern for social and emotional reasons.
Wearing a bra and getting your period around the same age as their peers is part of the social experience of young adolescents. Having a period at younger ages can be very challenging and stressful. Children may be teased, and they may suffer a blow to their self-esteem. Some girls have a hard time understanding what is happening with their bodies and what to share with their caregivers. Girls this age also tend to struggle with menstrual hygiene products. In some cases of normal puberty on the earlier side, I will work with families to make the menstrual cycle more manageable with medications.
When To Reach Out to a Doctor
What’s normal? What isn’t? The answer isn’t always clear cut, so I offer this guidance to parents about when to reach out to a doctor:
For worries about early puberty, contact your doctor if you notice:
- Breast development before age 8.
- Menstrual bleeding before age 8.
For worries about not reaching puberty, contact your doctor if you notice:
- No breast development by age 13.
- No period by age 15.
A doctor will take a detailed history and may order blood tests to check hormone levels and imaging exams to look at bone growth to determine whether treatment is needed.
Other reasons to reach out to your child’s doctor include:
- Menstrual bleeding that lasts eight days or longer per cycle
- Going more than three months between cycles. Irregular periods are very common in the first two to three years of menstruation, but I still encourage parents to reach out if more than three months lapse between their child’s periods just so we can be sure we aren’t missing another medical condition.
Heavy menstrual bleeding. This means needing to change a regular tampon more than once an hour, a disposable pad more than every two hours or period underwear more than twice a day.
I encourage parents to talk to their young adolescents about being honest and open about their periods. They should feel comfortable telling a parent about how often they change their pads, tampons or period underwear. They should learn how to count the days their bleeding lasts and how many days are between cycles – and to share that information with their parent(s). As doctors, we truly consider menstrual cycles to be another “vital sign,” in addition to blood pressure, heart rate and other important numbers.
Bottom line:
Remember that averages are just that – averages. But if your child does seem to be starting puberty at a young age, does not seem to be entering puberty by later in adolescence, or menstruates abnormally, reach out to your pediatrician.
Ariel Cohen, MD is a board-certified OB-GYN and pediatric and adolescent gynecologist with the Mid-Atlantic Permanente Medical Group. He sees patients at the Kaiser Permanente Capitol Hill Medical Center.
