Heart symptoms related to menstruation

The sex hormones may influence heart function

Young women with heart disease suffer worse symptoms at particular times during their monthly menstrual cycle, researchers have found.

The phenomenon of "menstrual angina" was uncovered by a team at St Thomas's Hospital, London.

Researchers examined nine women with arterial disease and symptoms of angina.

Angina is a cramp like pain from the heart associated with reduced blood flow to the heart muscle most usually due to atherosclerosis (hardening) of the coronary arteries.

The average age of the women was 38; four of them had already suffered a heart attack, and one had undergone bypass surgery.

Although this study is small it does raise some interesting questions about the effects of the sex hormones on the heart

British Heart Foundation

The women took an exercise treadmill test at the same time of day each week for four consecutive weeks, and the researchers measured how long it took for the women to experience angina pains.

They also took blood samples to measure hormone levels.

It was discovered that the women performed most poorly, and suffered the quickest pain when exercise in the week during or immediately after their period.

Sex hormones

This is known as the early follicular phase, and is the time when levels of the sex hormones oestrogen and progesterone are lowest.

The best performance and slowest time to angina pain occurred in mid-cycle, when oestrogen concentrations peak.

The researchers believe that the sex hormones act to expand the blood vessels, increasing blood flow through the arteries, and reducing pressure on the heart.

These hormones are also thought to influence the perception of pain, and general mood.

Previous research shows the severity of several conditions, such as migraine and asthma, varies throughout the menstrual cycle.

Lead researcher Dr Guy Lloyd told BBC News Online that despite the findings it was important that even women with very severe angina continued to exercise.

He said: "Women with angina should not however exercise beyond the point where they experience pain and consequently may be able to exercise less at low oestrogen times of the month."

A British Heart Foundation spokesman said: "Although this study is small it does raise some interesting questions about the effects of the sex hormones on the heart.

"We know that oestrogens have a protective effect on the heart in pre-menopausal women so it does seem logical that when hormone levels are low this protection may diminish temporarily.

"Whether this hypothesis is true or not is unclear so further research is important."

The research is published in the journal Heart.