What is Intrauterine Growth Retardation?

Intrauterine growth retardation (IUGR) is impaired fetal development that occurs in utero. Also known as intrauterine growth restriction, IUGR is a serious condition often triggered by the insufficient passage of nutrients from a mother to her unborn child. Suspected cases of intrauterine growth retardation may be closely monitored and necessitate premature delivery. The presence of intrauterine growth retardation may also result in intrauterine death.

As a fetus develops, its progress is closely monitored to ensure its development is occurring normally. Established, developmental markers are utilized to track the fetus’ development in relation to its gestational age, which is calculated in weeks. The normal gestation period for infants from conception to delivery is between 38 and 42 weeks. Infants delivered prior to 37 weeks are considered to be premature and are closely monitored.

The most common sign that the fetus may be suffering from intrauterine growth retardation is its small size. Pregnant women are sometimes able to intuitively know if the fetus is too small. Their suspicions may prompt an early doctor’s visit and additional testing, usually an ultrasound, to determine if the fetus is meeting gestational growth requirements. Other times, IUGR is usually detected during a routine doctor visit at which time an ultrasound may be performed to evaluate the fetus' condition.

While in utero, a fetus that does not receive proper nutrients from the mother may experience diminished growth and not meet developmental requirements. There are a variety of factors that influence fetal development, including the overall health of the mother. Pregnant women who have been diagnosed with heart disease or hypertension may be vulnerable to providing insufficient nourishment resulting in IUGR. In some cases, intrauterine growth retardation may occur as a result of placental issues, such as placenta previa, or the presence of disease or infection.

Viral and parasitic infections, such as rubella and toxoplasmosis, may disrupt the flow of proper nutrition from mother to child and contribute to intrauterine growth restriction. The presence of a sexually transmitted disease (STD), such as syphilis, may also adversely impact fetal development. Pregnant women who smoke or do not receive proper nutrients often possess an increased risk for intrauterine growth retardation.

Prognosis associated with intrauterine growth retardation is entirely dependent on the cause of the condition and its impact on fetal development at the time of diagnosis. The risk for complications to both the mother and child increase dramatically in the presence of intrauterine growth retardation and may sometimes require premature abdominal delivery. Most IUGR cases require regular monitoring of fetal development for any changes that may necessitate delivery.