الفهرس 
Introduction And Aim of the Work
PATHOGENESIS OF FETAL MACROSOMIAOnly 14 pages are availabe for public view
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Abstract
Macrosomic infants as well as their mothers are at increased riskfor intrapartuminury. Perinatal mortality is more common among thesefetuses.
The most commonly accepted definition for macrosomia is that ofbirth weight equal to or exceeding 4000g. According to ACOG (2000), itis reasonable to consider all newborn infants weighing 4500g or more asmacrosomic. The most recent studies reported an incidence of 8.9% forfetuses with macrosomia (>4000g).
Enlargement of the size of the fetus may be generalized or confinedto certain parts: head, neck, thorax, abdomen or pelvis. Enlargement ofthe size of the fetus as a whole may be symmetrical or asymmetrical.
The etiology of fetal macrosomia is believed to be multifactorial.Etiologic factors include gestational age, diabetes mellitus, male sex,multiparity, maternal weight gain during pregnancy, birth weight of aprior infant, ethnicity, smoking as well as genetic and congenitaldisorders.Many studies have largely defined the essential role of insulin,insulin like growth factors (IGF-I & IGF-II), and their receptors inembryonic and fetal growth. Other potential mechanisms of fetal somaticovergrowth include genetic factors, utero-placental constraints, thyroidand growth hormones, and leptin.Since its recognition, macrosomia has been one of the cornerstones of diabetic fetopathy. Hyperglycemia exists in women with poorlycontrolled diabetes, glucose crosses the placenta by facilitated diffusionand the fetus maintains a level of about 70-80% of the maternal glucoseconcentration. This results in a carbohydrate surplus to the fetus withsubsequent hyperinsulinemia. Fetal hyperinsulinemia causes directgrowth stimulation, increased cellular glucose utilization, increaseddeposition and decreased mobilization of fat and increased proteinproduction, this leads to overgrowth and the birth of a neonate withmacrosomia.
Fetal macrosomia has an important effect on maternal and fetalmorbidity and mortality. Maternal complications include arrest disorders,protraction disorders, instrumental delivery with more obstetriclacerations, post partum hemorrhage and puerperal infection, cesareandelivery and shoulder dystocia. Fetal complications include birth injuries,asphyxial injuries, neonatal hypoglycemia, and childhood and adolescentobesity.
Birth injuries include mainly brachial plexus injury and fractureclavicle. Brachial plexus injury results from downward traction on thebrachial plexus during delivery of the anterior shoulder. Erb’s palsy frominjury to the spinal nerves C5-6.
Accurate prenatal diagnosis of macrosomia is important forplanning and timing of the method of delivery.
There are three major strategies used to predict macrosomia whichare risk assessment, clinical estimation of fetal weight and ultrasonography. The strongest risk factor is maternal diabetes, whichresults in a two-fold increase in the incidence of macrosomia. Other riskfactors include prolonged gestation, obesity and multiparity. However,34% of macrosomic infants are born to mothers with no identifiable riskfactor.
Clinical estimation of fetal weight includes fundal level,measurement of the girth circumference at the level of the umbilicus as well as the measurement of symphysial- fundal height. Sonographic methods for diagnosis of macrosomia were developedin hopes of improving clinical estimates.
Type of the study:
Randomized controlled study will be done in department of obstetrics and gynecology Assiut University Hospitals.
Aim of the study:
To compare induction of labor versus expectant management in cases with large for gestational age fetuses in terms of neonatal morbidities and mortalities and cesarean section rate for arrest of labour due to oversized fetus.
A total of 42 caeses with estimated fetal weight more than 90% for gestational age at 38 weeks were divided into two groups 21 cases for each group.group (A) a total of 21 Women who had induction of labour at 38 weeks of gestation with estimated fetal weight more than 90% for gestational age. Group (B) atotal of 21 women who have estimated fetal weight more than 90% for gestational age at 38 weeks and allowed to waite for spontaneous onset of labour (expectant mangement).
1- Group A:
They managed by immediate induction of labour after electronic assessment of fetal well-being (contraction stress test) usingmisoprostol (misotac) 25µg every 6 hours vaginally to the posterior fornix
2- Group B: Women allowed waiting for spontaneous onset of labour (expectant managemen).
RESULTS
There is no significant difference between the two group as regard the csrate,induction of labour at 38 weeks does not increase or decrease the csrate,neonatal and maternal morbidities and mortalities when compared with expectant management in pregnancies with EFW >90% forgestational age.