Changes in ultrasonography indicators of abnormally invasive placenta during pregnancy

Abstract

The prevalence of ultrasonography signs suggestive of AIP varied throughout pregnancy. During the early first trimester, indicators of AIP were similar to those of a cesarean scar pregnancy; classical ultrasonography signs of AIP were already present at 11-14 weeks of pregnancy for most patients.

Diagnostic accuracy of ultrasound in detecting the depth of invasion in women at risk of abnormally invasive placenta: A prospective longitudinal study

“…We have previously shown that ultrasound signs suggestive of AIP were present in a large majority of affected women already since the first trimester of pregnancy and that there was no difference in the distribution of such signs between the second and third trimester, even in cases with placenta percreta . Despite this, longitudinal assessment of women at risk for AIP through the third trimester is fundamental in order to delineate more accurately the extent and topography of placental invasion, which may become evident only later on in gestation.…”

Early first‐trimester transvaginal ultrasound is indicated in pregnancy after previous Cesarean delivery: should it be mandatory?

“…However, previa in the setting of CSP is an entirely different scenario and frequently these abnormally implanted placentae not only fail to resolve, but also hint at underlying invasion. Furthermore, one of the hallmark diagnostic findings for CSP, namely low anterior gestational sac position between 5 and 7 weeks, correlated 100% of the time with development of PAS. Given this well‐documented connection, we argue that CSP, which we know can be diagnosed accurately in the early first trimester, can itself serve as the sought‐after early‐pregnancy sonographic marker for predicting PAS.…”

“…Fortunately, two easily applicable methods are available to facilitate the diagnosis of CSP and differentiate it from a correctly implanted intrauterine pregnancy. These use evaluation of sagittal ultrasound images to determine the location of the center of the gestational sac relative to transverse and/or longitudinal ,42 lines that are placed specifically on the image to mark the lower and/or anterior halves of the uterus.…”

“…Fortunately, two easily applicable methods are available to facilitate the diagnosis of CSP and differentiate it from a correctly implanted intrauterine pregnancy. These use evaluation of sagittal ultrasound images to determine the location of the center of the gestational sac relative to transverse and/or longitudinal ,42 lines that are placed specifically on the image to mark the lower and/or anterior halves of the uterus. These methods work best if applied in the early first trimester, since after that point, the growing gestational sac begins to fill the uterine cavity, distorting the location of initial implantation, although the placenta and associated vessels remain in place; such assessment has up to 98.9% specificity and 93% sensitivity when used between 5 and 10 weeks' gestation.…”

Placental Malformation: Accreta and Beyond

“…Ultrasonography is the primary screening tool for placental invasion in women at high risk of AIP usually performed during the second and third trimesters of pregnancy [8][9][10]. Its sensitivity for the diagnosis of AIP ranges from 77 to 93% and specificity from 71 to 97% according to a recent review [6,8,11], but its sensitivity and specificity may increase to 100% when applied to a high-risk population [3].…”