الفهرس 
Intrauterine Growth RestrictionOnly 14 pages are availabe for public view
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Abstract
I
ntrauterine growth restriction (IUGR) is a syndrome characterized by a deficiency of fetal growth compared to the normal standards for the gestational age (GA). IUGR affects approximately 3 to 7% of all pregnancies. The growth restricted fetus is at increased risk for morbidity and mortality, it is estimated that perinatal mortality is 5-10 times higher in growth restricted fetus than those of the same GA and appropriate size.
These infants are at high risk of perinatal hypoxia, acidemia, operative delivery, neonatal encephalopathy and other neonatal problems including hypoglycemia, hypothermia, hypocalcaemia and polycythemia.
IUGR results from several causes including fetal causes (eg chromosomal abnormality, Congenital malformation, STORCH infection, multifetal gestation and choronic placental abruption) and maternal causes (eg poor maternal weight gain, smoking, alcohol intake, addiction, choronic disease eg hypertension and diabetes with pregnancy).
Growth restriction occurs with significant frequency in pregnant women with preexisting type 1 diabetes but it can occar in type 2 diabetes especially if there is underlying maternal vascular disease (eg retinal or renal vasculopathies and/or chronic hypertension). Intensive glycemic control (especially in diabetics with IUGR due to placental vascular insufficiency) may deprive fetus from nutrition. Secondly frequent hypoglycemia which are inevitable complication of insulin treatment may further worsen the IUGR.
Preeclampsia may cause fetal growth failure and is an indicator for its severity, especially when onset is before 37 weeks. Some forms of IUGR have been etiologically linked to preeclampsia based on the similarities underlie the hypothesis that preeclampsia and IUGR are secondary to placental insufficiency. They share cause but have different clinical manifestations.
Chronic hypertension especially when complicated by pre-eclapmsia, renal diseases, cyanotic heart diseases and anemia are all associated with FGR.
Various methods for diagnosis of IUGR are encountered including clinical method eg Symphysis-fundal height (SFH) measurement and ultrasound assessment including measurement of fetal weight by Biparietal diameter(BPD), abdominal circumference (AC)(most important) and femur length (FL).
According to ultrasound finding, IUGR is diagnosed as small for gestational age (SGA) with weight below the 10th percentile (P10) or the population mean minus 2 standard deviations of a population based normogram.
Doppler information of fetal systemic vessels helps the obstetrician in managing pregnancies complicated by IUGR. Doppler signal characteristics aid in the decision making when to time the delivery. Further, the rate and degree of deteriorating doppler signals are closely related to the risks for adverse perinatal outcome. Longitudinal observations of fetal doppler changes in growth-restricted fetuses demonstrate progressive deterioration of umbilical artery (UA) blood flow, followed by middle cerebral artery (MCA) velocimetry and finally ductus venosus (DV) blood flow.
Brain perfusion in growth-restricted fetuses shows clear regional variations, which change with progression of hemodynamic deterioration. It has been reported that after an initial and early increase perfusion in the frontal area (in early IUGR) , progression of fetal deterioration is rapidly associated with a pronounced decrease in frontal perfusion, together with an increase toward the basal ganglia(in late IUGR) . This is called Brian sparing effect. It is significantly associated with an adverse perinatal outcome in IUGR.
Hemodynamic redistribution was defined according to the following criteria: for MCA measurements, as the presence of a pulsatility index (PI) in the fetal MCA below the fifth centile for GA. For the 3D power Doppler indices as the presence of a value of vascularization index (VI), flow index (FI), or vascularization flow index (VFI) above the 95th centile for gestational age.
3D power Doppler studies may add valuable information in an attempt to achieve an earlier prediction of the mechanism involved in the fetal hemodynamics centralization.
This new technique include a qualitative evaluation by means of 3D reconstruction of the vascular structure of a region of interest (ROI). In this study ,the regions of interest are Zone 1(sprinkled mainly by anterior cerebral artery) obtained by tracing the contour of the anterior part of the fetal brain up to the perpendicular line crossing the anterior delineation of the cavum septum pellucidi (CSP) and zone 2(sprinkled mainly by middle cerebral artery) ) was defined by a rectangle reaching from both temporal bones with the width of CSP included.
The volume of the investigated zones and the blood flow indices were calculated using Virtual Organ Computer-aided Analysis (VOCAL) software, was used to calculate the 3D power doppler indices from the samples of the fetal head obtained from the volume acquired by using the histogram facility of the VOCAL software. The following Doppler indices can be calculated: Vascularization index (VI), Flow index FI), and Vascularization flow index (VFI).
IUGR was divided into 3 groups according to 2D power doppler parameters as follow: group 1 (had normal UA PI, MCA PI and DV PI), group 2 (had abnormal UA PI but normal MCA PI and DV PI) and group3 (had abnormal UA PI, MCA PI and DV PI). Also IUGR was divided into early onset (GA <34 weeks) and late onset IUGR (GA >34 weeks). Each group was compared with controls and with each other as regarding 3D ultrasound parameters.
Results:
Regarding demographic data: this study showed no statistically significant difference between cases and controls regarding maternal age and body mass index (BMI).
Regarding obstetric history: this study showed no statistically significant difference between cases and controls regarding parity, mode of previous deliveries, previous abortion, IUFD, IUGR and stillbirth.
Regarding GA in weeks at delivery: GA was lower in cases than controls.
Regarding neonatal outcomes: birth weight in grams was lower in cases than controls, APGAR score in one and five minutes were lower in cases than controls and NICU admission was higher in cases than controls,
Regarding 2D ultrasound parameters: MCA PI and UA PI were higher in cases compared to controls while DV PI was lower in cases compared to controls.
In comparison between asymmetrical and symmetrical IUGR: UA PI was higher in asymmetrical than symmetrical IUGR but no statistically significant difference between asymmetrical and symmetrical IUGR regarding MCA PI and DV PI.
In comparison between early or late onset IUGR and controls: UA PI was higher in early onset IUGR than controls but MCA PI and DV PI showed no statistically significant difference between early onset IUGR and controls. The MCA PI was higher in late onset IUGR than controls but UA PI and DV PI showed no statistically significant difference between late onset IUGR and controls.
As regarding 3D ultrasound parameters:
In zone 1: VI, FI, VFI showed no statistically significant differences between cases (either early onset or late onset IUGR) and controls.
group 1 and group 3 IUGR showed no statistical significant difference between them and control group regarding VI, FI and VFI.
group 2 IUGR showed no statistical significant difference between it and control group regarding VI and VFI but FI was higher in controls than group2 IUGR.
In zone 2: VI and VFI showed statistically significant difference between cases and controls with higher levels in the cases. FI showed no statistically significant differences between cases and controls.
group 1: VI, FI and VFI showed no statistically significant difference between them and controls.
group 2: VI and VFI were higher in group 2 than controls but FI showed no statistically significant difference between them and controls.
group 3: VI, FI and VFI showed statistically significant difference between them and controls with high level in group 3.
Early onset IUGR: VI, FI and VFI were higher in early onset IUGR than controls.
Late onset IUGR: VFI was higher in late onset IUGR and controls.