How Is Adult Height Predicted?
The Mid-Parental Height (MPH) method is the most widely used clinical tool for predicting a child's adult height. It accounts for both parents' heights and adjusts for the biological sex of the child. Genetics accounts for approximately 80% of height variation, with nutrition, sleep, exercise, and health making up the remaining 20%.
Mid-Parental Height Formula
Boys: MPH = (Father's height + Mother's height + 13) ÷ 2
Girls: MPH = (Father's height + Mother's height − 13) ÷ 2
Predicted range: MPH ± 8.5 cm (covers ~95% of children)
Girls: MPH = (Father's height + Mother's height − 13) ÷ 2
Predicted range: MPH ± 8.5 cm (covers ~95% of children)
Factors That Affect Height
| Factor | Impact |
|---|---|
| Genetics | ~80% — dominant factor |
| Nutrition (protein, calcium) | ~10% — crucial in childhood |
| Sleep & growth hormone | ~5% — peak release during deep sleep |
| Exercise & physical activity | ~3% — stimulates growth hormone |
| Health conditions | Variable — untreated hypothyroidism, celiac disease can stunt growth |
When Do Children Stop Growing?
- Girls: Typically reach full height 2–3 years after first period (around age 14–16)
- Boys: Usually stop growing around age 16–18, with some continuing until 21
- Growth plates (epiphyseal plates) fuse at the end of puberty, stopping vertical growth
When to consult a doctor: If your child's height falls below the 3rd percentile on growth charts, or if growth velocity slows significantly, consult a pediatrician or pediatric endocrinologist.