الفهرس 
Introduction
Placenta Accreta HistoryOnly 14 pages are availabe for public view
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Abstract
Placenta accreta is a substantially life threatening condition and one of the causes of maternal morbidity and mortality in the world. Life-threatening obstetric hemorrhage, unplanned cesarean hysterectomy, and complications related to the abnormal invasion of the placenta into adjacent organs are the catastrophic morbidities associated with placenta accreta. Additionally, there has been increase in placenta accreta rate over the last decades. This increase is not uniformly distributed but associated with variations among and within countries.
Because placenta accreta can lead to life-threatening blood loss, identification of these high-risk patients would be helpful in management of the pregnancy in addition to enabling the surgeon to be prepared adequately before the time of delivery. Many studies have been done on identification of placenta accreta in the third trimester by 2D ultrasound and color Doppler. But few studies have been done on identification of placenta accreta in the early pregnancy with limited number of cases and retrospective design.
Early suspicion and diagnosis of placenta accreta in the first trimester provide an ample opportunity to counsel the patient about potential antepartum and intrapartum complications, allow for appropriate surveillance, and provide valuable information for a patient to make informed decisions about the remainder of the pregnancy. In the event of impending miscarriage or a decision to terminate the pregnancy, an earlier diagnosis has the potential to improve patient safety because physicians and staff can take appropriate steps to ensure the availability of blood products, assemble the proper surgical personnel, and schedule the appropriate surgery and surgical time
This is a prospective study is conducted in Obstetrics and Gynecology Department, Women Health Centre, Faculty of Medicine, Assiut University and covering the period from March 2016 to September 2019. It was aimed to early prediction of placenta accreta. First of all, we have passed through a screening phase of the participants to ensure their gestational age using Naegle’s rule and/or CRL. Then the eligible participants according to inclusion criteria (1st trimester pregnancy between 11 weeks and 20 weeks and at least one of the following signs suggestive of placenta accreta; low implantation of the gestational sac, presence of placental lacunae, Disruption of placental-myometrial interface and gestational sac or placenta overlapping a uterine scar by 2D transvaginal ultrasound and Intraplacental dilated vessels and greatly increased periplacental vascularity by Doppler ultrasound) and exclusion criteria (Cases far away from our hospital and expected to be lost to be followed and pregnant women who refused to Participate (after informed verbal consent) were searched for the pre mentioned signs suggestive of placenta accreta by level II sonographer and co-investigator under his supervision using Medison SONOACE X6 ultrasound device.
The selected participants had been coming for antenatal care at regular visits. At 31-34 weeks, the selected participants was investigated for placenta praevia, loss or irregular retroplacental sonolucent zone, abnormal placental lacunae and thinning or disruption of the hyperechoic serosa bladder interface by transabdominal and two dimensional transvaginal ultrasound and investigated for vascular lacunae with turbulent flow within the placenta (PSV ≥ 15 cm / sec) and hypervascularity of serosa–bladder interface using the same device by same investigator.
At time of delivery, diagnosis of placenta accreta was done clinically by difficult manual, piecemeal removal of placenta if there was no evidence of placental separation 20 minutes after parturition, despite active management in third-stage labor.
In our prospective study, we found that all cases with placental invasion had at least one of the searched predictor two dimensional and Doppler ultrasound signs of placental invasion, while either of these signs was present in only about half of cases without placental invasion and this was significant. Regarding each sign alone, all cases of placental invasion were having low sac implantation with no cases of placenta accreta among those with sac in normal. In addition, placental invasion was associated significantly with placental lacunae, number of CS ≥3 and Gestational sac or placenta overlapping the uterine scar. Oppositely, disruption of placental myometrial-interface had no significant difference between the two groups.
Because the low sac sign was present in all cases of placenta accreta we did sub group analysis for the low sac cohort. The incidence of the two dimensional ultrasound and Doppler Parameters in the low sac cohort among the group of placental invasion and the non-invasion group was the same as in the entire cohort. Furthermore, number of CS ≥3 was significantly higher with the invasion group.
Regarding third trimester, we found a very strong association between placenta accreta and previa where all cases of placenta accreta were placenta previa and neither of cases of placenta accreta was not placenta previa. Additionally, placental invasion was associated significantly with Irregular or loss of retroplacental sonolucent zone, placental lacunae, Thinning or disruption of the hyperechoic serosa bladder interface and Hypervascularity of serosa bladder interface. On the opposite side, presence of vascular lacunae with turbulent flow within the placenta (PSV ≥ 15 cm / sec) had no significant difference between the two groups.
In trial to standardize prediction of placenta accreta in early pregnancy, we created a scoring index for prediction of placenta accreta at early pregnancy (Assiut index for prediction of placenta accreta in early pregnancy). We found that a score derived from variables which were statistically significant from first trimester two dimensional transvaginal (2D) ultrasound parameters and Doppler ultrasound parameters; gestational sac or placenta overlapping the scar, Intraplacental dilated vessels and Placental lacunae in addition to number CS ≥3 was highly predictive of placental invasion early in pregnancy among pregnancies at increased risk with low sac implantation.
The application of the Assiut index for prediction of placenta accreta in early pregnancy can be helpful in identification of pregnant women at high risk of placenta accreta at early pregnancy. For this, the cut off point for prediction of placenta accreta in the score was >4.5 with the highest possible specificity (95%) and associated sensitivity (77%). Assigning a scoring index for prediction of placenta accreta in early pregnancy in clinical practice may be helpful in interpreting these various sonographic variables in light of the patient’s history (number of prior CS).
As an example, if a woman who has had 3 prior cesarean deliveries with low implanted sac is found to have gestational sac or placenta overlapping the scar, and Placental lacunae she would receive 2 points for the prior cesarean deliveries, 1 point for placental lacunae and 2.5 points for gestational sac or placenta overlapping the scar. This would result in a score of 5.5 which is more than 4.5 indicating high risk of placenta accreta. Conversely, a woman with 2 prior cesarean deliveries (0 point), placental lacunae (1 point), Intraplacental dilated vessels (1.5 points), and trophoblast away from the scar (0 points) would have a score of only 2.5 which is less than 4.5 indicating low risk of placenta accreta. According to the availability of local resources and multidisciplinary care, results from our scoring index could thus be used for counseling and assist with referral decisions in case.