--- title: "Menarche: The Start of Menstrual Periods | Sutter Health" description: "Does a girl have to reach a certain weight before her periods begin?" url: "/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208" --- 1. Home / 2. Menarche: The Start of Menstrual Periods # Menarche: The Start of Menstrual Periods * * * Medically reviewed by - Toni J Brayer, M.D. ## Question Does a girl have to reach a certain weight before her periods begin? ## Answer Menarche (the start of a girl's menstrual period) is not dependent upon weight alone but the amount of body fat, height and weight all play a role in determining the start of puberty. A woman's genes and the age her mother began her period is a major factor in determining when a girl will have her period. There are other physiologic and environmental events that also matter and girls develop at different rates depending upon geography and ethnicity. Every girl develops at a different rate but most girls have their first period by age 15 or 16. In the United States the median age of menarche is 12.43 years and 90 percent of all girls have their period by the time they are 14 years old. These statistics have not changed in the last 40 years in the United States. ## Explore related topics Children's healthMenstruation ## Related questions View all questions - Health Q&A ### Bedwetting Causes and Treatment What causes bedwetting? My grandson (age 11) has wet the bed continuously. The medication he was given didn't help. He says he just can't wake up and sleeps right through it. I want him to feel good about himself, so I'm reaching out for any guidance. - Health Q&A ### Circumcise an Older Child? I chose not to circumcise my son. Now the AAP issued a policy statement that actively endorses circumcision. While my son is only two years old, I worry that I made the wrong decision. Should I have him circumcised now? - Health Q&A ### Low-Carb Diet for Children? With all this talk about carbs being the enemy, is a low-carb diet appropriate for children? - Health Q&A ### Melatonin for Kids? My sister-in-law's pediatrician recommended melatonin to help her three-year-old go to sleep at night. She says it works well. But how safe can this type of thing be for toddlers? - Health Q&A ### Nosebleed Causes and Prevention My 7-year-old son gets nosebleeds often. What causes them and can they be prevented? View all questions ```json {"@context":"https://schema.org","@type":"MedicalOrganization","name":"Sutter Health","@id":"https://www.sutterhealth.org/#medicalorganization","url":"https://www.sutterhealth.org","logo":"https://www.sutterhealth.org/static/images/sutter-health-logo.svg","address":{"@type":"PostalAddress","streetAddress":"2200 River Plaza Drive","addressLocality":"Sacramento","addressRegion":"CA","postalCode":"95833","addressCountry":"US"},"areaServed":{"@type":"AdministrativeArea","name":"California"},"sameAs":["https://www.facebook.com/SutterHealth","https://www.instagram.com/sutterhealth/","https://x.com/SutterHealth","https://www.youtube.com/sutterhealth","https://www.linkedin.com/company/sutter-health","https://en.wikipedia.org/wiki/Sutter_Health"]} ``` ```json {"@context":"https://schema.org","@type":"BreadcrumbList","@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#breadcrumblist","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://www.sutterhealth.org/"},{"@type":"ListItem","position":2,"name":"Menarche: The Start of Menstrual Periods"}]} ``` ```json {"@context":"https://schema.org","@type":"MedicalWebPage","@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#medicalwebpage","url":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208","name":"Menarche: The Start of Menstrual Periods","description":"Menarche (the start of a girl's menstrual period) is not dependent upon weight alone but the amount of body fat, height and weight all play a role in determining the start of puberty.","inLanguage":"en-US","medicalAudience":{"@type":"MedicalAudience","audienceType":"Patient"},"isPartOf":{"@id":"https://www.sutterhealth.org/ask-an-expert/answers"},"breadcrumb":{"@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#breadcrumblist"},"mainEntity":{"@type":"Question","@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#question","name":"Menarche: The Start of Menstrual Periods","text":"Does a girl have to reach a certain weight before her periods begin?","acceptedAnswer":{"@type":"Answer","@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#answer","text":"Menarche (the start of a girl's menstrual period) is not dependent upon weight alone but the amount of body fat, height and weight all play a role in determining the start of puberty. A woman's genes and the age her mother began her period is a major factor in determining when a girl will have her period. There are other physiologic and environmental events that also matter and girls develop at different rates depending upon geography and ethnicity. Every girl develops at a different rate but most girls have their first period by age 15 or 16. In the United States the median age of menarche is 12.43 years and 90 percent of all girls have their period by the time they are 14 years old. These statistics have not changed in the last 40 years in the United States.","url":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208","author":{"@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#expert"}}},"publisher":{"@id":"https://www.sutterhealth.org/#medicalorganization"},"reviewedBy":{"@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#expert"}} ``` ```json {"@context":"https://schema.org","@type":"Person","@id":"https://www.sutterhealth.org/ask-an-expert/answers/menarche-the-start-of-menstrual-periods-1051061208#expert","name":"Toni J Brayer","honorificSuffix":"M.D."} ```