Heart disease risk in pregnancy fainting

When women faint during pregnancy, they often consider the occurrence normal and fail to worry about it.

Over the years, health experts have linked fainting to fluctuations in blood pressure, high temperatures, anaemia, dehydration and morning sickness occurring during pregnancy.

“I fainted a couple of times during my early days of pregnancy. But the doctor assured me that it was nothing to worry about, as this is a common symptom of pregnancy,” said Roselyn Mumbi, whose son is now two years old.

“Luckily, the episodes ended after the first trimester and I ended up having a healthy child. So I don’t think much about it.”

But unknown to women such as Roselyn, the fainting episodes may have long-term effects on their health and that of their children.

New research published in the American Heart Association Journal shows that fainting may be an indicator of health issues for both the mother and child, especially when it occurs during the first trimester.

The study, conducted by a team of cardiology researchers, reviewed birth records of 481,930 babies born in Alberta, Canada between 2005 and 2014.

They also looked at medical records of the mothers for one year after delivery to determine the frequency, timing and outcomes of fainting episodes.

Results showed that roughly one percent of expectant mothers fainted. About a third did so during the first three months of pregnancy.

Among the pregnancies where fainting occurred during the first trimester, the research team observed higher rates of preterm births, an increase in heart problems and further fainting episodes for the mothers.

There was also an increase in congenital anomalies (birth defects) such as low birth weight among babies when the mothers had passed out more than once.

“I want to see fainting included with other pregnancy induced conditions like pre-eclampsia and gestational diabetes as a warning sign for the cardiovascular health of mothers,” said Padma Kaul, a cardiology researcher and professor of medicine at the University of Alberta who conducted the study.

As such, she advised women who faint during pregnancy to report the incidence to their doctors. “The physicians should monitor the mothers, and their babies more closely.”

According to Kaul, pregnancy is a natural stress test for a woman's system and may thus identify those that are at a higher risk of cardiovascular complications down the road.

Past research on fainting during pregnancy has mainly relied on anecdotal reporting and a small number of case studies. The Alberta study was the first to assess the problem using population-based data over a long period of time.

The researchers noted that the findings were surprising as they were contrary to common belief that fainting during pregnancy is harmless.

"Fainting is a relatively rare event and nobody has studied it systematically at a population level. Generally, clinicians thought it was fairly non-threatening. So that's what we were expecting to find."

Fainting, medically known as syncope, is a temporary loss of consciousness. It is usually caused by low blood pressure and a lack of oxygen in the brain.

In early pregnancy, a hormone known as progesterone usually makes the veins widen, leading to a drop in blood pressure.

This results in dizziness and fainting episodes, which may be worse if the mother stands or sits too quickly.

During the late stages of pregnancy, drops in blood pressure that cause fainting usually happen when the weight of the baby squeezes blood vessels in lower parts of the body (such as the legs and pelvis) — especially when mothers lie on their backs.

To prevent such problems, women are advised to lie on their side and use pillows to support the baby ‘bump’.

They should also sit up slowly — while coming up — after lying down for any length of time.

Feeling warmer during pregnancy is normal and is as a result of hormonal changes and more blood going to the skin's surface.

But extremely hot weather and intense exercises can cause the body to overheat, leading to fainting episodes.

Drinking plenty of water during hot days can help address this challenge. Being well hydrated prevents low blood pressure caused by dehydration that usually causes dizziness and fainting.

On average, pregnant women need at least eight glasses of water daily. The quantities should increase on very hot days.

In addition, women can lower body temperatures on hot days by using fans or sponging the face and hands with cool water.

Sitting with the head between the knees or lying down to enable blood flow to the head can help prevent feelings of dizziness and avert fainting. Those already lying down can move on their left side.

Taking deep breathes, loosening tight clothing and opening any doors or windows is also recommended.