Birth weight and cardiovascular health – where is the connection?

How much did you weigh at birth? Your baby/babies? Does it matter?

A new study by British researchers published in the European Heart Journal shows that there is a link between low birth weight and predisposition to hypertension later in life.

Increasing evidence suggests that adverse prenatal environments, as indicated by low birth weight, cause long-term changes in cardiovascular physiology that predispose to circulatory disease.

The study followed up 140 healthy children aged 7 to 9 years old who were born at full-term, had a wide-range of birth weights though still considered normal. Blood pressure and heart rate (by ECG) were regularly monitored. In addition, the children were also subjected to psychological stress tests (e.g. speaking in public, mental arithmetic task) and the response in the form of cardiac impedance was measured.

The results show that there birth weight is linked to certain cardiovascular response to stress. However, the relationship is different depending on gender. Boys with low birth weights are more like to have higher vascular resistance and higher blood pressure during the stress test. In girls, this link is not evident. However girls with low birth weight tended to have higher activity of the sympathetic nervous system in response to stress. This is the part of the nervous system usually located in the spinal cord and is responsible for regulation of many processes in the body, including stress response. Both responses translate to a predisposition to cardiovascular problems later in life.

The study concludes

Smaller size at birth is associated with sex-specific alterations in cardiac physiology; boys had higher systemic vascular resistance and girls had increased cardiac sympathetic activation.

The results of this study are based on children with birth weights considered to be low, nevertheless still within a range considered normal.

Can you imagine what possible health problems premature babies with below normal birth weights can have? A baby is considered premature when born before the 37th week of gestation. Premature babies – preemies for short – tend to be smaller and weigh less than full-term babies. Several studies have shown that preemies are more likely to have health problems ranging from respiratory problems to autism

This doesn’t mean that preemies are doomed to be ill for the rest of their lives. My twins were born 5 weeks early but I didn’t resign myself to the fact that they will be just as healthy as their peers just because they were small babies. I strongly believe in the power of prevention through a healthy lifestyle. Exercise, proper nutrition, and the right attitude can make a lot of difference and I can to attest this when I look at how my boys can outrun and outcycle other kids of their age.

Still, now that the health consequences of low birth weight are known, pregnant and wanna-be pregnant women should pay closer attention to factors that can affect a fetus’ growth in the womb – and these include maternal nutrition, smoking, and alcohol consumption.

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