IUGR

Liam suffered from IUGR. He stopped growing in the womb because I had suffered a uterine rupture. After he was born, we got two different birth weights. The one at the hospital he was born at, when they had weighed him several hours after birth when he was already fully swollen and the one UCSF estimated his actual birth weight being. They swelling was caused by CDH. The first hospital weighed him swollen at 4 pounds 5 ounces. UCSF estimated his actual birth weight at only 2 pounds 4 ounces. They said he'd swollen at least half his size. It wasn't until the swelling went down that we saw how tiny he really was. It was terrifying as a parent to see a baby that small and to have so many medical problems on top of it.  

Intrauterine growth restriction (IUGR) refers to poor growth of a baby while in the mother's womb during pregnancy. The causes can be many, but most often involve poor maternal nutrition or lack of adequate oxygen supply to the fetus.

At least 60% of the 4 million neonatal deaths that occur worldwide every year are associated with low birth weight (LBW), caused by intrauterine growth restriction (IUGR), preterm delivery, and genetic/chromosomal abnormalities, demonstrating that under-nutrition is already a leading health problem at birth.

The term IUGR is not synonymous with Small for Gestational Age (SGA). SGA refers to a birth weight that is below the 10th percentile for gestational age. Not all fetuses with IUGR are classified as SGA, and vice versa. IUGR is used to describe a pattern of intrauterine fetal growth that deviates from expected norms, whereas SGA is a category assigned based on birth weight.

There are 2 major categories of IUGR: symmetrical and asymmetrical.

Asymmetrical IUGR is more common. In asymmetrical IUGR, there is restriction of weight followed by length. The head continues to grow at normal or near-normal rates (head sparing). This is a protective mechanism that may have evolved to promote brain development. This type of IUGR is most commonly caused by extrinsic factors that affect the fetus at later gestational ages.

Symmetrical IUGR is less common and is more worrisome. This type of IUGR usually begins early in gestation. Since most neurons are developed by the 18th week of gestation, the fetus with symmetrical IUGR is more likely to have permanent neurological sequela.

Maternal[edit]

• pre-pregnancy weight and nutritional status
• poor weight gain during pregnancy
• poor nutrition
• anemia
• alcohol and/or drug use
• maternal smoking
• recent pregnancy
• pre-gestational diabetes
• gestational diabetes
• pulmonary disease
• cardiovascular disease
• renal disease
• hypertension

Uteroplacental

• preeclampsia
• multiple gestation
• uterine malformations

Fetal

• chromosomal abnormalities
• intrauterine infection

If the cause of IUGR is extrinsic to the fetus (maternal or uteroplacental), transfer of oxygen and nutrients to the fetus is decreased. This causes a reduction in the fetus’ stores of glycogen and lipids. This often leads to hypoglycemia at birth. Polycythemia can occur secondary to increased erythropoietin production caused by the chronic hypoxemia. Hypothermia, thrombocytopenia, leukopenia, hypocalcemia, and pulmonary hemorrhage are often results of IUGR.

If the cause of IUGR is intrinsic to the fetus, growth is restricted due to genetic factors or as a sequela of infection.

Neurological Development Postpartum

IUGR is associated with a wide range of short- and long-term neurodevelopmental disorders

Cerebral Changes

white matter effects – In postpartum studies of infants, it was shown that there was a decrease of the fractal dimension of the white matter in IUGR infants at one year corrected age. This was compared to at term and preterm infants at one year adjusted corrected age.

grey matter effects – Grey matter was also shown to be decreased in infants with IUGR at one year corrected age.

Neural Circuitry and Brain Networks

Children with IUGR are often found to exhibit brain reorganization including neural circuitry.[2] Reorganization has been linked to learning and memory differences between children born at term and those born with IUGR.[3]

Studies have shown that children born with IUGR had lower [intelligence quotient|IQ]. They also exhibit other deficits that point to [frontal lobe] dysfunction.

IUGR infants with brain-sparing show accelerated maturation of the [hippocampus] which is responsible for memory.[4] This accelerated maturation can often lead to uncharacteristic development that may compromise other networks and lead to memory and learning deficiencies.

IUGR affects 3-10% of pregnancies. 20% of stillborn infants have IUGR. Perinatal mortality rates are 4-8 times higher for infants with IUGR, and morbidity is present in 50% of surviving infants.

#IUGR #cdhawareness