Definition infants whose weight is < 10th %ile for a particular GA weight not associated with any constitutional or familial ca...
Definition
- infants whose weight is < 10th %ile for a particular GA
- weight not associated with any constitutional or familial cause
- prone to problems such as meconium aspiration, asphyxia, polycythemia, hypoglycemia, and mental retardation
- greater risk of perinatal morbidity and mortality
Etiology
Maternal causes
- poor nutrition,
- cigarette smoking,
- drug abuse, alcoholism,
- cyanotic heart disease,
- severe DM,
- SLE,
- pulmonary insufficiency
Maternal-fetal
- any disease which causes placental insufficiency leading to inadequate transfer of substrate across the placenta
- includes PIH, chronic HTN, chronic renal disease, gross placental morphological abnormalities (infarction, hemangiomas)
Fetal causes
- TORCH infections,
- multiple gestation,
- congenital anomalies
Symmetric/Type I (20%)
- occurs early in pregnancy
- inadequate growth of head and body although the head:abdomen ratio may be normal
- usually associated with congenital anomalies or TORCH
Asymmetric/Type II (80%)
- occurs late in pregnancy
- brain is spared therefore the head:abdomen ratio is increased
- usually associated with placental insufficiency
- more favorable prognosis than Type I
- clinical suspicion
- SFH measurements at every antepartum visit
- more thorough assessment if mother is in high risk category or if SFH lags > 2 cm behind GA
- U/S exam should include assessment of BPD, head and abdomen circumference, head:body ratio, femur length and fetal weight
- doppler analysis of umbilical cord blood flow
- prevention via risk modification prior to pregnancy ideal
- most important consideration is accurate menstrual history and GA in which to assess the above data
- modify controllable factors: smoking, alcohol, nutrition
- bed rest (in LLD position)
- serial BPP (monitor fetal growth)
- delivery when extrauterine existence is less dangerous than continued intrauterine existence or if GA > 34 weeks with significant oligohydramnios
- liberal use of C-section since IUGR fetus withstands labour poorly
