Presentation on theme: "INTRAUTRINE GROWTH RESTRICTION"— Presentation transcript:
1 INTRAUTRINE GROWTH RESTRICTION Dr. Miroslawa Bednarek
2 Diagnosis of symptomFetal growth failing (arising from maternal, placental, or fetal origins)Birth weight lower than expected in the suitable gestational week (may be the variable described as below the 3rd, 5th, or 10th percentile)A perinatological definition of fetal IUGR
3 Dynamic phenomenon defined the best A a delay of the growth of the fetus estimated as a decrease of 25 centiles in the measure of the abdominal circumference, according to the standard curve at the gestational age, and in subsequent echograhic evaluations performed at least every 2 weeks.
4 ClassificationAsymmetrical (late onset – around 30 weeks of pregnancy) – affects abdominal growth more that the head circumference.Symmetrical (early – from the beginning of the second trimester) – proportional lagging of the head circumference, abdominal circumference, and long bone growth.
5 Natural History The first 16 weeks of pregnancy – cellular hyperplasia From 16 to 32 weeks of pregnancy, both cellular hyperplasia and cellular hypertrophy occur.The last weeks, cellular hypertrophy predominates
7 Risk factors – placental : Abnormalities of the placentation (reduction of number of thin-walled, distended uteroplacental vessels)Acute atherosisObliteration of small muscular arteries of the tertiary villiConfined placental mosaicismChorioangioma
10 Clinical features :Clinical examination (symphyseal – fundal distance)Diagnostic ultrasound (BPD, FL, AC, EFW) – serial measurementsAFI – amniotic fluid indexMaturity of the placenta – stages according to Grannum
11 Doppler examinationUterine arteries – approximately 25% of women with unilateral persistant notch and 50% of those with bilateral notch at 24 weeks of pgregnancy will have an IUGR fetus, develop pre-eclampsia, or experience both (sensitivity 82% and specificity of 38%)Umbilical arteries – affected fetuses show a reduced blood flow pattern during diastole
12 Fetal compromiseGradually increasing resistance to blood flow in umbilical arteriesEnd diastolic component may disappear or may reverseRedistribution of blood flow occursBrain, heart and adrenal glands are preferentially perfusedMCA blood flow increases
13 Brain Sparing Phenomenon Cerebroplacental ratio is below 2 SDPrior to abnormal CTG recordings about a couple days to 2 weeksAssociated with fetal hypoxiaWhen resistance in MCA begins to rise – cerebral edema occurs
14 Utero-placental insufficiency during pregnancy Diagnosis and management
15 During pregnancy, fetus depends on the placenta and umbilical vessels for transport of oxygen and nutrients from maternal blood, and for excretion of carbon dioxide and products of metabolism
16 During pregnancy and labor, fetus may be at risk of damage or death from acute or chronic utero-placental insufficiency.
17 Acute placental failure may result from placental separation by hemorrhage (abruptio placentae) or it may come at the end of a phase of gradually declining placental efficiency.
18 Chronic restriction of maternal blood flow through the placenta can have a serious effect upon fetal growth and development.
19 Medical History : Pregnancy induced hypertension Maternal diseases (DM; severe anemia; renal, intestinal, cardiac and lung failures; malnutrition)Infections in pregnancyMultiple pregnanciesSome drugsAddictions (smoking, alcohol, drug abuse)Placental pathology (placental infarction, fetal stem artery thrombosis, antepartum, hemorrhage)
20 Tests of placental function : Maternal weightUterine growth – fundal heightFetal body movementsFetal growth – obtained by ultrasoundFetal activity – biophysical profile, non-stress test (CTG)Color doppler studiesPlacental biochemical tests
21 Maternal weightShould normally increase by about 0.5 kg weekly after the first trimester (provided that the patient is not dieting or vomiting and has no other disorder causing malnutrition)Components of this weight gain include: the fetus, plcenta, liquid, uterus, breasts and fat store. Additionally there is the increase in blood volume and ECF.These changes depend directly on placental function, or indirectly by the hormone production
22 Uterine growthSimple measurements of the height of the fundus of uterus in relation to the symphysis pubis and umbilicus (eg. in 16th week of gestation – midpoint between pubic symphysis and the umbilicus; at 24th week – umbilical level)Fundal height should increase by about 1 cm weekly from the 16th week of pregnancy, and with an average sized fetus, should equal the number of weeks of gestation plus or minus 2cm
23 Fetal body movementsThe most important indication of placental function is the well being of the fetusThe oldest and simplest method of evaluation of the fetal well being is “kick count”Mother is asked to note how frequently the fetus moves in a gives period of time, perhaps in 30 minutesAlternatively, she can be asked to note how long it takes for the fetus to move 10 times
24 Fetal growth Dating a pregnancy Serial measurements obtained with ultrasoundBPD, AC, HC/AC, FL, EFWCenters of ossification in long bones – to confirm fetal maturityDetecting congenital abnormality
25 Fetal activityContinuous record of FHR over a period of 30 minutes or more – so called NST (non stress test). It includes recording of changes in FHR variability (from beat to beat) in association with fetal movements and uterine contractions – cardiotocography (CTG)Biophysical profile – a score based on real time ultrasound observation of fetal breathing, gross body movements, tone and amniotic fluid volume
26 Stress testIn a case of doubtful or suspicious results of non stress testContraction stress test – CSTOxitocin challenge test – OCTFetal acoustic stimulation test – FAST
27 Color Doppler examination Reflection of ultrasound waves from the wave produced by the pulse of blood moving along a blood vessel is detected and compared with the energy output of the sourceThis provides a measure of the speed of passage of the pulse wave and appears as a typical shape of blood waveformSeems to be the most useful tool in prediction of chronic fetal hypoxia
28 Biochemical markers of placental function Evaluation of functional activity of the placenta by measuring one or more of its hormone or enzymes products in maternal blood or urineExcretion of estriol in the maternal urine during 24 hour period gives an indication of placental function, isolated observations are of little value, but related observations may show an obvious trendOther tests: serum levels of placental lactogen and of heat stable alkaline phosphatase