الفهرس 
Acknowledgemen
Fetal MacrosomiaOnly 14 pages are availabe for public view
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Abstract
The term biacromial diameter means the distance between the outermost points of fetal shoulders; the mean newborn shoulder width is 122,06mm (Verspyck et al., 1999).
Fetal macrosomia may be defined as a birth weight >4000 g and occurs as a complication in more than 10% of all pregnancies in the United States of America (Zamorski et al., 2001).
It is associated with increased risks of cesarean section and trauma to the birth canal and fetus. Prediction of fetal macrosomia may be performed using clinical and ultrasonographic evaluation.
The average risk of shoulder dystocia when birth weight >4.5kg varies from 9% to 24% (ACOG 2013).
` Gherman et al., (Gherman 2006) in their review article on the uncommon obstetric emergency, noted that shoulder dystocia is characterized as the failure of delivery of the fetal shoulder(s), whether it is the anterior, posterior, or both fetal shoulders.
Gherman et al, (Gherman et al., 2006) in a comprehensive review of shoulder dystocia in 2006, stated that “when evaluated in a prospective fashion” pre-pregnancy and antepartum risk factors have “exceedingly poor predictive value for prediction of shoulder dystocia.” Lewis etal. (Lewis et al., 1998) found that only 25% of all shoulder dystocia cases had one or more significant risk factors. The American College of Obstetricians and Gynecologists (ACOG 2002) echoes these thoughts in its practice bulletin on shoulder dystocia, stating that “shoulder dystocia cannot be predicted or prevented because accurate methods for identifying which fetuses will experience this complication do not exist.”
Identifying formulae that are able to accurately predict the fetal weight in these populations can be of great help to the caring obstetrician.
Formulae based exclusively on the abdominal circumference (AC) are thought to predict the fetal weight more accurately in preterm babies than in term fetuses (Schild etal., 2004).
Shepard et al. have suggested that formulae based on the biparietal diameter (BPD) and AC predict accurately the fetal weight within 10% of the actual weight (Shepard, 1982).
The addition of femur length (FL) seems to improve the accuracy of fetal weight prediction (Isobe etal., 2004).
Formulae that combine AC, BPD and FL are reported to have the best prediction for fetal weight (Ratanasiri etal., 2002)
The ethnic background affects fetal biometry and birth weight and this is attributed to genetic differences rather than nutritional or socioeconomic circumstances (Jacquemyn etal., 2000).
The present study is prospective cross sectional study that aims to assess the accuracy of ultrasonography for measurement of fetal biacromial diameter in comparison to newborn measurement after delivery, also to know if measurement of fetal biacromial diameter is helpful or not for prediction of fetal macrosomia and shoulder dystocia.
Fetal biacromial diameter is measured by proposed ultrasound formula: transverse thoracic diameter+ midarm diameter ×2.
Neonatal biacromial diameter is measured by two boards are added to each side of the shoulder then the distance between the outer most points of newborn shoulder is measured.
Results of the current study demonstrate that, there is no significant statistical difference between fetal and neonatal biacromial diameter (table10), also there is no significant statistical difference between fetal and neonatal abdominal circumference (table14).
There was proportional relationship between biacromial diameter, abdominal circumference and estimated fetal weight (table18).
Percentage of macrosomia associated with high abdominal circumference was 96,4% (ROC curve1).
Percentage of macrosomia associated with high biacromial diameter was 96,4% (ROC curve2).
percentage of shoulder dystocia associated with high abdominal circumference was 100% (ROC curve 3).
Percentage of shoulder dystocia associated with high biacromial diameter was 95% (ROC curve 4).
The proposed ultrasound formula for measurment of fetal biacromial diameter is more likely accurate to the biacromial diameter of the neoborn after deliveryWhen the abdominal circumferencer greater than 35.5cm, this predict fetal macrosomia (4000gm) with sensitivity 96.4% and spesificity 96.93%.
When the proposed fetal biacromial diameter greater than 15.4cm, this predict fetal macrosomia with sensitivity 96.4% and specificity 97.14% which is near to the predictive value of abdominal circumference.
When the abdominal circumference greater than 35.5cm, this predict shoulder dystocia with sensitivity 100% and specivicity 80.1%, but when the proposed fetal biacromial diameter greater than 15.4cm, this predict shoulder dystocia with sensitivity 95% and specificity 86.07%.