intrauterine growth restriction, IUGR

Intrauterine growth restriction, or IUGR, denotes the condition of intrauterine stunting of the fetus due to poor infant nutrition and general life support, or intrinsic factors in the fetus itself.

The most common identifiable causes of IUGR are of course maternal smoking, high blood pressure, poor diet, maternal substance abuse, or serious medical disease during pregnancy. Rare causes include growth restriction in one of twins who receives much less than his fair share of nutrients while the bulk of blood flow is shunted to his luckier sibling. This occurs through accidents of placental malformation, and can lead to very striking differences in size between twins.

Of course, intrauterine growth restriction can certainly occur for reasons beyond either mothers' or physicians' control: placental insufficiency for example, and other factors that we simply do not understand or over which we have no control. Certain genetic syndromes involve growth retardation, as do undetected maternal infections such as toxoplasmosis, rubella, or cytomegalovirus.

Marked IUGR is associated with permanent stunting of body size, as well as lower IQ scores. For this reason, good prenatal care as well as healthy habits and a good diet for expectant mothers are obviously very important.

This condition used to be called "intrauterine growth retardation," but Terry J. DuBose, M.S., RDMS, Program Director of Diagnostic Medical Sonography at the University of Arkansas for Medical Sciences, informs me that:

"In contemporary OBGYN sonography terminology IUGR has become the acronym for 'Intrauterine Growth Restriction,' rather than the older 'Intrauterine Growth Retardation.' This change in vernacular was made because sonographers often found that parents tended to focus on the word 'retardation' rather than 'growth' and they misconstrued it to mean mental retardation. This misconception is probably due to the anxiety associated with receiving any news of their child other than perfectly good news."

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