---
title: What are normal menstrual patterns? | Niyora
description: Normal cycles last 21-35 days with 1-7 days of bleeding. About 43% of women experience menstrual pain and 75% experience premenstrual tension.
url: https://niyora.com/research/papers/menstrual-characteristics-of-2-343-women-attending-the-shepherd-foundation-1979/
---

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- What are normal menstrual patterns?

Study, 1979

# What are normal menstrual patterns?

Normal cycles last 21-35 days with 1-7 days of bleeding. About 43% of women experience menstrual pain and 75% experience premenstrual tension.

 Early or limited evidence

2,343 women attending the Shepherd Foundation Health Testing Centre

## What they did

Analyzed menstrual information from 2,343 women using a computer system to identify common patterns in cycle length, bleeding duration, menstrual pain, and premenstrual tension.

## What they found

Menstrual pain was reported by 43% of women. Premenstrual tension was reported by 75%. Normal cycle length ranges from 21-35 days, with only 1.5% having cycles shorter than 21 days. Normal bleeding duration is 1-7 days, with only 3% bleeding longer than 7 days. The researchers found 150 different patterns of menstrual symptoms. The 10 most common patterns accounted for 40% of the population, and most of these included both menstrual pain and premenstrual tension.

## What it means for you

Menstrual pain and premenstrual tension are very common. Three-quarters of women experience premenstrual tension. This large study shows what's normal for menstrual cycles. However, it was done at one health center, so it may not represent all populations equally.

2,343

women studied

75%

experienced premenstrual tension

43%

experienced menstrual pain

## About the study

Original title Menstrual characteristics of 2,343 women attending the Shepherd Foundation Authors Wood C, Larsen L, Williams R Journal The Australian & New Zealand journal of obstetrics & gynaecology Year 1979 Study design Study Participants 2,343 What was tested No intervention Read the paper [doi.org/10.1111/j.1479-828x.1979.tb01366.x](https://doi.org/10.1111/j.1479-828x.1979.tb01366.x)

## Topics

[Premenstrual syndrome (PMS)](https://niyora.com/research/topics/condition-pms/)[Dysmenorrhea and period pain](https://niyora.com/research/topics/condition-dysmenorrhea/)[Anxiety and tension](https://niyora.com/research/topics/symptom-anxiety/)[Pain and headache](https://niyora.com/research/topics/symptom-pain/)

Research tells you what helps on average. Niyora helps on the day it hits.

Calm down, see it another way, and decide what to say, with a PMS and PMDD app built by a doctor.

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