History

Fact Explanation
History of intra uterine infection / chromasomal abnormalities [1] Herpes, cytamegalo virus, rubella, toxoplasmosis can give rise to fetal growth restriction ( <10% of all cases of fetal growth restriction). Trisomies 13,18,21 and malformation syndromes can cause growth impairment due to reduced cell number. [1]
Multiple gestation [2] Can cause fetal growth restriction (FGR) due to decreased placental mass, abnormal placentation and placental vascular defects. [1]
History of abnormal placentation [2] Abruptio placentae, Placenta previa, Infarction, Circumvallate placenta, Placenta accretia can cause growth retardation due to poor blood supply [1]
Maternal diseases [1] Maternal vascular disorders (diabetes, hypertension) , collagen disorders such as SLE, antiphospholipid syndrome can cause FGR as vascular diseases cause reduced utero-placental blood flow [1]
Pregnancy induced hypertension [1] Pre eclampsia caused by abnormal trophoblatic invasion of spiral arterioles ultimately causes luminal narrowing and give rise to poor blood flow [1]
Cyanotic heart disease / pulmonary disease [1] Causes poor fetal oxygenation due to chronic hypoxia [1]
Use of teratogenic drugs [2] Anticonvulsants, coumarins , cocaine cause poor fetal weight gain [1]
References
  1. PELEG D, KENNEDY CM, HUNTER SK. Intrauterine growth restriction: identification and management. Am Fam Physician [online] 1998 Aug, 58(2):453-60, 466-7 [viewed 24 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/9713399
  2. BAMFO JACQUELINE E. A. K., ODIBO ANTHONY O.. Diagnosis and Management of Fetal Growth Restriction. Journal of Pregnancy [online] 2011 December, 2011:1-15 [viewed 24 August 2014] Available from: doi:10.1155/2011/640715

Examination

Fact Explanation
Abdominal palpation - symphisio fundal height [1] Abdominal palpation has a sensitivity of 30% for detecting SGA (smaal for gestational age) fetuses. The symphysis-fundal distance has a sensitivity of 27–86% and specificity of 80–93% for detecting SGA [1]
Low body mass index [2] Poor maternal nutrition is an identified cause of fetal growth restriction [2]
High blood pressure [3] Pre eclampsia can cause fetal growth restriction.Diagnostic criteria for preeclampsia are systolic blood pressure of 140 mmHg or more or a diastolic blood pressure of 90 mm Hg or more on two occasions at least six hours apart [3]
Fetal heart rate [1] Heard with a pinard. Fetal tachycardia occurs with compromise of fetal blood flow [1]
References
  1. BAMFO JACQUELINE E. A. K., ODIBO ANTHONY O.. Diagnosis and Management of Fetal Growth Restriction. Journal of Pregnancy [online] 2011 December, 2011:1-15 [viewed 24 August 2014] Available from: doi:10.1155/2011/640715
  2. PELEG D, KENNEDY CM, HUNTER SK. Intrauterine growth restriction: identification and management. Am Fam Physician [online] 1998 Aug, 58(2):453-60, 466-7 [viewed 24 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/9713399
  3. LEEMAN L, FONTAINE P. Hypertensive disorders of pregnancy. Am Fam Physician [online] 2008 Jul 1, 78(1):93-100 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/18649616

Differential Diagnoses

Fact Explanation
Constitutionally Small Fetus [1] Ethnic and geographic differences. Small built parents. Doppler studies and bio physical profile are normal [1]
References
  1. PELEG D, KENNEDY CM, HUNTER SK. Intrauterine growth restriction: identification and management. Am Fam Physician [online] 1998 Aug, 58(2):453-60, 466-7 [viewed 24 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/9713399

Investigations - for Diagnosis

Fact Explanation
Ultra sound scan - dating scan [1] Accurate dating in early pregnancy is essential for making the diagnosis of IUGR (intra uterine growth retardation). The usual qualifier for reliable dating and establishment of an accurate gestational age is a certain date for the last menstrual period in a woman with regular cycles or assessment of gestational age by an ultrasound examination performed no later than the 20th gestational week, when the margin of error is seven to 10 days [1]
Ultra sound scan - fetal anatomy [2] Fetal anatomical estimations are an important indicator of IUGR. 1st trimester - crown rump length 2nd trimester - biparietal diameter, head circumference, abdominal circumference, femur length. Ultrasound determination of head circumference, biparietal diameter, femur length, and abdominal circumference can be used to derive an EFW (estimated fetal weight). When fetal growth can be followed by serial estimates of fetal weight, a diagnosis of IUGR may be established from falling percentiles in a chart of EFW plot against gestational age [2]
Ultra sound scan - amniotic fluid assessment [2] The assessment of amniotic fluid is an integral part of any ultrasound examination of fetal growth. Amniotic fluid volume can be reported either as the maximum vertical pocket, or the four-quadrant AFI (amniotic fluid index). Low amniotic fluid volume may reasonably be defined after 37 weeks as an AFI < 5 cm or as a maximum vertical pocket < 2 cm. The combination of IUGR and polyhydramnios (AFI > 25 cm) suggests non-placental fetal causes [2]
Non-Stress Test [1] This is one of the first tests used in the surveillance of IUGR fetuses and the simplest to perform. The physician uses a heart rate monitor to determine changes in the fetal heart rate with fetal movement. If the heart rate increases more than 15 beats for more than 15 seconds, this is considered to be a reactive test. If the heart rate does not accelerate, remains flat, or decreases, then this is an abnormal test. The problem with this test is that it changes late in the course of the disease and does not identify a fetus with IUGR. When patients are diagnosed with IUGR and require continuous monitoring, the fetal heart rate tracing may be useful in detecting fetal distress [1]
References
  1. PELEG D, KENNEDY CM, HUNTER SK. Intrauterine growth restriction: identification and management. Am Fam Physician [online] 1998 Aug, 58(2):453-60, 466-7 [viewed 24 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/9713399
  2. FIGUERAS FRANCESC, GARDOSI JASON. Intrauterine growth restriction: new concepts in antenatal surveillance, diagnosis, and management. American Journal of Obstetrics and Gynecology [online] 2011 April, 204(4):288-300 [viewed 24 August 2014] Available from: doi:10.1016/j.ajog.2010.08.055

Investigations - Fitness for Management

Fact Explanation
Oral glucose tolerance test [1] Important to detect gestational diabetes, as this can cause fetal growth restriction. Diagnostic values : 1 hour blood glucose level ≥180 mg/dl (10 mmol/L) 2 hour blood glucose level ≥155 mg/dl (8.6 mmol/L) [1]
Protein in urine [2] To detect pre eclampsia, as it can cause fetal growth restriction. pre eclampsia: proteinuria (>300 mg of protein in a 24-hour urine sample) [2]
References
  1. Gestational Diabetes Mellitus. Diabetes Care [online] 2003 January, 26(90001):103S-105 [viewed 24 August 2014] Available from: doi:10.2337/diacare.26.2007.S103
  2. ROBERTS J. M., PEARSON G., CUTLER J., LINDHEIMER M.. Summary of the NHLBI Working Group on Research on Hypertension During Pregnancy. Hypertension [online] December, 41(3):437-445 [viewed 18 August 2014] Available from: doi:10.1161/​01.HYP.0000054981.03589.E9

Investigations - Followup

Fact Explanation
Umbilical artery doppler studies [1] Indicate the blood flow in umbilical artery. When oligohydramnios is found and IUGR (intra uterine growth restriction) is suspected from fetal biometry, umbilical cord artery Doppler studies are indicated. As placental insufficiency worsens, diastolic flow progressively decreases. Absent or reversed end-diastolic velocities are mostly found in early-onset IUGR [1]
middle cerebral artery (MCA) doppler studies [1] Indicate the blood flow in middle cerebral artery. Longitudinal studies on deteriorating early-onset IUGR fetuses have reported that the pulsatility index in the MCA progressively becomes abnormal. In late-onset IUGR, there is observational evidence that MCA vasodilatation is associated with adverse outcome independently of the umbilical artery [1]
fetal biophysical profile (BPP) [1] The fetal biophysical profile (BPP) is a group of measurements that includes the amniotic fluid volume, fetal tone, fetal movements, fetal breathing movements, and fetal heart rate monitoring (NST). When normal, each parameter receives two points, for a maximum total of ten points. The BPP is usually performed to lower the false positive rate of the NST; however, the BPP has a false positive rate ranging from 75% for a score of six to 20% for a score of zero. The main advantages of the BPP test are the direct assessment of fetal behavior and the technical ease in performing the test. The disadvantages are the performance time required (at least 30 minutes), the dependence on visual interpretation of the NST, and the indirect provision of information regarding fetal cardiovascular status and perfusion. If evaluation of the AFI reveals oligohydramnios, this calls for further evaluation irrespective of the overall score [1]
Venous doppler [1] Reflects fetal cardiac function. Predictive of adverse perinatal outcome. Blood flow should always be antegrade. Absent or reversed flow is always abnormal. [1]
References
  1. FIGUERAS FRANCESC, GARDOSI JASON. Intrauterine growth restriction: new concepts in antenatal surveillance, diagnosis, and management. American Journal of Obstetrics and Gynecology [online] 2011 April, 204(4):288-300 [viewed 24 August 2014] Available from: doi:10.1016/j.ajog.2010.08.055

Investigations - Screening/Staging

Fact Explanation
Growth curves [1] The most widely used definition of IUGR (intra uterine growth restriction) is a fetus whose estimated weight is below the 10th percentile for its gestational age. (Estimated fetal weight is plot against the gestational age ) IUGR is usually classified as symmetric and asymmetric. Symmetric growth restriction implies a fetus whose entire body is proportionally small. A fetus with asymmetric IUGR has a normal head dimension but a small abdominal circumference (due to decreased liver size)(plotting the abdominal circumference and the head circumference against gestational age in the same chart) [1]
Bio chemical markers ( eg: hCG , alpha fetoprotein) [2] In the first trimester an unexplained low, pregnancy associated plasma protein A or hCG has an increased risk of intra uterine growth restriction (IUGR). In the second trimester, an unexplained elevation of serum alpha a-fetoprotein, hCG, or inhibin-A is also associated with these adverse outcomes [2]
References
  1. PELEG D, KENNEDY CM, HUNTER SK. Intrauterine growth restriction: identification and management. Am Fam Physician [online] 1998 Aug, 58(2):453-60, 466-7 [viewed 24 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/9713399
  2. FIGUERAS FRANCESC, GARDOSI JASON. Intrauterine growth restriction: new concepts in antenatal surveillance, diagnosis, and management. American Journal of Obstetrics and Gynecology [online] 2011 April, 204(4):288-300 [viewed 24 August 2014] Available from: doi:10.1016/j.ajog.2010.08.055

Management - General Measures

Fact Explanation
Patient education [1] Risk to the baby: Increased risk for cesarean delivery Increased risk for hypoxia (lack of oxygen when the baby is born) Increased risk for meconium aspiration, which is when the baby swallows part of the first bowel movement. This can cause the alveoli to be over distended, a pneumothorax to occur, and/or the baby can develop bacterial pneumonia. Hypoglycemia (low blood sugar) Polycythemia (increased number of red blood cells) Hyperviscosity (decreased blood flow due to an increased number of red blood cells) Increased risk for motor and neurological disabilities [1]
General measures [1] Treatment of maternal disease, cessation of substance abuse, good nutrition and institution of bed rest [1]
References
  1. PELEG D, KENNEDY CM, HUNTER SK. Intrauterine growth restriction: identification and management. Am Fam Physician [online] 1998 Aug, 58(2):453-60, 466-7 [viewed 24 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/9713399

Management - Specific Treatments

Fact Explanation
Asprin ( anti platelet therapy ) [1] The use of low-dose asprin therapy in populations at high risk, such as those with abnormal uterine artery Doppler studies, is controversial. Recommended to start at early pregnancy - before 20th gestational week ( placental development occurs at this gestational age )[1]
Antenatal steroids [1] Antenatal steroids are prescribed to promote fetal lung maturity, if the fetus is below 34-35 weeks [1]
Magnesium sulfate [1] MgSO4 during the first trimester may also be beneficial. MAGPIE trial showed that magnesium sulphate halves the relative risk of eclampsia, without appearing to have substantive harmful effects on either the mother or the baby in the short term [2] Also, Magnesium deficiency might be one of the causes of IUGR, and magnesium sulfate treatment was effective [1]
Timing of delivery [1] If isolated IUGR: deliver at 38 0/7 to 39 6/7 weeks. If IUGR with additional risk factors eg oligohydramnios, abnormal Doppler, maternal risk factors or co-morbidities, aim tp deliver between 34 0/7 – 37 6/7 weeks [1]
Mode of delivery [1] IUGR is not a contraindication for induction of labour or vaginal delivery unless there are other contraindications (eg: cephalo pelvic disproportion ). Continuous fetal monitoring (use of cardiotocography) during labour is necessary. Low-threshold for caesarean section. If umbilical artery doppler studies show absent or reversed end diastolic volume, delivery by caesarean section is recommended [1]
Intra partum management [1] Uteroplacental insufficiency may be exacerbated by labour, Higher risk of cesarean section, Close monitoring in labor is indicated [1]
References
  1. PELEG D, KENNEDY CM, HUNTER SK. Intrauterine growth restriction: identification and management. Am Fam Physician [online] 1998 Aug, 58(2):453-60, 466-7 [viewed 24 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/9713399
  2. MAGPIE TRIAL FOLLOW-UP STUDY COLLABORATIVE GROUP. The Magpie Trial: a randomised trial comparing magnesium sulphate with placebo for pre-eclampsia. Outcome for women at 2 years BJOG [online] 2007 Mar 1, 114(3):300-309 [viewed 25 August 2014] Available from: doi:10.1111/j.1471-0528.2006.01166.x