Every additional year between a woman's first period and her menopause reduces her risk of stroke and angina by 3 percent, new research reveals. 

Having a 36-to-40 'reproductive year' span is the most protective against heart disease, a study found.

These findings are thought to be due to the hormone estrogen's protective role against heart disease.

Previous research has revealed estrogen helps to keep blood vessels flexible, allowing them to expand and contract.

Inflexible blood vessels is a known cause of heart disease.

How the study was carried out  

Researchers from the University of Florida analyzed 3,081 women aged 60 and over.

The study's participants provided information regarding their first period and the age they were when menopause began.

They were then divided into those who had more than 30 years between their first period and menopause, known as the reproductive years, and those that had 30 years or less. 

The participants were also asked whether they had any heart or circulatory disease.  

Key findings  

Longer reproductive years is associated with a reduced risk of stroke and angina.

A reproductive year span of 36-to-40 years is the most protective against heart disease.

Every one additional reproductive year reduces the risk of suffering a heart-related event by 3 percent.

This is thought to be due to estrogen's cardioprotective effects.  

The findings were published in the Journal of Women's Health.   

Dr Susan Kornstein, editor-in-chief of the journal, who was not involved in the study, said: 'By evaluating women's risk of cardiovascular and cerebrovascular events based on the duration of their reproductive years, rather than just their age at menarche or their age at menopause as individual variables, [the researchers] take into account the effect of cumulative exposure to sex hormones such as estrogen.'