Most girls grow about 2 to 3 inches (5 to 7.5 cm) after their first period. Growth typically continues for around 3 years after menarche, but the rate slows significantly because the fastest growth spurt has already passed.
Why Growth Slows After the First Period
The first period arrives about a year after a girl’s peak height velocity, which is the point during puberty when she’s growing the fastest. That peak is when girls commonly gain 3 to 4 inches in a single year. By the time menstruation starts, the most rapid phase of growth is already in the rearview mirror.
The reason comes down to estrogen. During early puberty, low levels of estrogen actually stimulate growth. As puberty progresses and estrogen levels rise higher, the effect reverses: estrogen signals the growth plates (the soft cartilage near the ends of long bones) to gradually harden and close. Once those plates fully fuse, no more height gain is possible. This process takes roughly 3 years after the first period, which is when most girls reach their adult height.
What the Growth Timeline Looks Like
The 2 to 3 inches of remaining growth don’t happen evenly. Most of that height is gained in the first year or so after the first period, when the growth plates are still fairly active. The second year adds less, and by the third year, growth has usually slowed to a fraction of an inch before stopping entirely.
A rough breakdown looks something like this:
- Year 1 after first period: 1 to 2 inches of growth
- Year 2: 0.5 to 1 inch
- Year 3: minimal growth, approaching final adult height
These numbers are averages. Some girls gain slightly more, others slightly less, depending on genetics, when puberty started, and overall health.
Early vs. Late Periods and Final Height
A common worry is that getting a period early means ending up shorter. There’s some truth to this, but the picture is more nuanced than it first appears. Girls who start their period early (say, at age 10) have less total growing time ahead of them compared to girls who start at 13 or 14. However, early developers also tend to be taller than their peers at the time their period arrives, because their growth spurt kicked in sooner.
Late bloomers, on the other hand, may feel shorter during middle school but often catch up because they have more years of pre-pubertal growth. The relationship between the timing of the first period and final adult height is real but complicated by genetics. Two girls who start their periods years apart can still end up the same height as adults if their genetic potential for height is similar.
When Early Puberty Affects Adult Height
True precocious puberty, where a girl begins developing before age 8, is a different situation. When puberty starts very early, the growth plates can close before a girl has had enough years of childhood growth, potentially reducing her final adult height. Treatment with hormone therapy to pause puberty can help in some cases, with treated girls gaining an average of 7 cm (about 2.75 inches) more than untreated girls in one study. The benefit is greatest when treatment begins before age 6, variable between ages 6 and 8, and generally offers no height advantage after age 8.
For girls whose periods start within the typical range of 9 to 15, this isn’t a concern. Normal variation in the timing of puberty does not usually require any medical intervention.
Factors That Affect Remaining Growth
While genetics set the ceiling for your height, a few practical factors influence whether you actually reach that ceiling during the remaining years of growth after your first period.
Sleep matters more than most people realize. Growth hormone is primarily released during deep sleep. One bad night won’t make a difference, but chronic sleep deprivation over months or years can suppress growth hormone enough to affect height. Teenagers need 8 to 10 hours of sleep per night, and this is especially important while the growth plates are still open.
Nutrition plays a major role as well. Adequate protein, calcium, vitamin D, and overall calorie intake support bone growth. Restrictive dieting during the teen years, or conditions that interfere with nutrient absorption, can limit how much of your genetic height potential you reach. This doesn’t mean extra vitamins or supplements will make you taller than your genes allow, but falling short on basic nutrition can hold you back.
Overall health is the third piece. Chronic illnesses, untreated thyroid conditions, or prolonged use of certain medications (like corticosteroids) can slow growth. For most healthy teens, though, these aren’t factors.
Estimating Your Adult Height
If you’re wondering how tall you’ll end up, there are a few rough methods. The simplest is mid-parental height: add your parents’ heights together, subtract 5 inches (for girls), and divide by two. This gives a rough estimate with a margin of about 2 inches in either direction.
Another old rule of thumb is to double a girl’s height at 18 months of age, though this is obviously less useful if you’re already a teenager looking for answers.
For a more precise estimate, a doctor can order a bone age X-ray, which shows how mature the growth plates are. Comparing your bone age to your actual age reveals whether you have more or less growing time than average. A bone age that’s younger than your real age means more growth is still ahead. A bone age that matches or exceeds your real age means you’re closer to done.
None of these methods are perfectly accurate, but they can give you a reasonable range to expect. The most reliable predictor remains your family history: if your parents and grandparents are tall, you’re likely to be tall too, regardless of exactly when your period arrived.