---
title: Why do some women get cold sores around their period? | Niyora
description: Women with recurrent cold sores have lower protective immune proteins and higher inflammation proteins throughout their cycle. This immune weakness suggests t
url: https://niyora.com/research/papers/lower-interleukin-2-and-higher-serum-tumor-necrosis-factor-a-levels-are-2000/
---

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- Why do some women get cold sores around their period?

Survey study, 2000

# Why do some women get cold sores around their period?

Women with recurrent cold sores have lower protective immune proteins and higher inflammation proteins throughout their cycle. This immune weakness suggests the virus reactivates more easily around the period.

 Early or limited evidence

21 women aged 19-26: 10 with recurrent premenstrual herpes simplex infection, 11 without

## What they did

21 women aged 19-26 were examined at five points during their menstrual cycle. 10 women had recurrent cold sores (usually days 18-25). 11 women without cold sores were compared. Researchers measured immune proteins and hormones in their blood.

## What they found

Women with recurrent cold sores had lower IL-2 throughout the cycle, with sharper drops on days 18 and 25. They also had higher TNF-alpha on day 18 and higher IL-6 throughout the cycle. Both groups had increases in TNF-alpha around menstruation.

## What it means for you

Immune system weakness (low protective proteins, high inflammation) may allow herpes to reactivate around the period. The main limits are the small sample size and that this measures proteins, not whether they directly cause cold sores.

21

women total

10

with recurrent cold sores

11

without cold sores

## About the study

Original title Lower interleukin-2 and higher serum tumor necrosis factor-a levels are associated with perimenstrual, recurrent, facial Herpes simplex infection in young women Authors Myśliwska J, Trzonkowski P, Bryl E et al. Journal European cytokine network Year 2000 Study design Survey study Read the paper [https://pubmed.ncbi.nlm.nih.gov/11022124/](https://pubmed.ncbi.nlm.nih.gov/11022124/)

## Topics

[Cognition, concentration and memory](https://niyora.com/research/topics/symptom-cognition/)[Adolescents and young people](https://niyora.com/research/topics/life-area-adolescents/)

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