Objective:

To compare between the role of Transabdominal ultrasound versus Transvaginal ultrasound in evaluation of placental invasion in cases of placenta previa anterior wall with previous uterine scar applying the unified ultrasonographic descriptors suggested by the European working group on abnormally invasive placenta "EW-AIP' Also to evaluate the sensitivity and specificity of each criterion by comparing them with the final outcome of pregnancy Fifty pregnant women with persistent placenta previa (after 28 weeks' gestation) were prospectively enrolled into this study. Both transabdominal and transvaginal ultrasound were performed by two different operators who were blinded to the results of each other.

the placenta was studied as regarding the exact loacalization and the unified descriptors were applied and evaluated by TAS and TVS.

The ultrasound findings were analyzed with reference to the final diagnosis made during Cesarean delivery and histopathological examination

Definitive diagnosis of Abnormally Invasive Placenta was made at delivery when the myometrium was seen to be invaded by the placenta, and the pathological examination of the removed uterus showed the villi attached to the myometrium without intervening decidua (accreta), invading into the myometrium (increta) or reaching the serosa (percreta).

-Complete imaging using all diagnostic techniques (gray-scale, color Doppler) by both transabdominal and transvaginal by two expert operators, then an offline analysis of the acquired images & volumes was done Ultrasound examination was performed using a 2D ultrasound system equipped with a 4-8-MHz trans-abdominal transducer and a 12 MHz transvaginal transducer The transvaginal ultrasound was performed by a highly experienced operator whereas the transabdominal ultrasound was performed by a less experienced one and both were blinded from the results of each other Placenta was examined while the bladder was partially full about 300 ml for adequate visualization and precise localization

The Examined placenta is considered to be suspicious of abnormal invasion in case of having one or more of the unified descriptors described by the European working Group on Abnormally Invasive Placenta "EW-AIP":

Inclusion Criteria:

• Pregnant women in the reproductive age group (18 - 45) diagnosed persistent placenta previa anterior wall after 28 weeks of gestation , with history of previous Caesarian Section and/or any other type of uterine surgeries

Exclusion Criteria:

• Placenta previa posterior wall
• unscarred uterus

Pregnant women in the reproductive age group (18 - 45) diagnosed persistent placenta previa anterior wall after 28 weeks of gestation , with history of previous Caesarian Section and/or any other type of uterine surgeries