Data of eligible patients were reviewed and abstracted using a
standardized spreadsheet that comprise patient baseline information(e.g. age, parity, body mass index “BMI”, ethnicity, smoking
status), obstetric and gynaecologic data (e.g. obstetric
complications, previous CS, prior gynaecologic surgeries), medical
history, antepartum and intrapartum disease characteristics (e.g.
PAS type, complete versus focal uterine wall invasion, bladder invasion,
parametrial invasion, placental location), diagnosis (antepartum
versus intrapartum diagnosis, imaging modality, and gestational age at
diagnosis), antepartum haemoglobin level, intraoperative details(e.g. hysterectomy versus uterine preservation, uterus preserving
procedures used either surgical or IR-related, success of uterine
preservation, use of preoperative or intraoperative sonographic
assessment, type of uterine incision and its relation to the placenta,
intraoperative blood loss, transfused blood products, surgical
complications), maternal outcomes (success of uterine
preservation, length of hospital stay, admission to intensive care unit
[ICU], postoperative complications), and neonatal outcomes. Data
collection was completed on June 15th, 2020.
Primary outcome of the study was massive PAS-associated blood loss. This
indicates intraoperative blood loss equal to or greater than 2500 ml,
blood loss necessitating massive blood transfusion (defined as
transfusion of at least 10 units of packed red blood cells [RBCs]
within 24 hours) or disseminated intravascular coagulopathy (DIC)
secondary to intraoperative blood loss.
Statistical analysis
Continuous variables were described in means and standard
deviations/medians and interquartile ranges (IQR), and categorical
variables were summarized in numbers and percentages. Shapiro-wilk test
was used to test normality of distribution; parametric variables were
compared using student’s t test while non-parametric variables were
tested using Mann-Whitney U test. Logistic regression was used to test
association between the primary independent variable (uterus
preservation vs. caesarean hysterectomy), with adjustment for potential
confounders, and outcomes (massive PAS-associated blood loss and
admission to ICU). Each independent variable was first tested using
univariable logistic regression and results were expressed in unadjusted
odds ratio (OR) and 95% confidence interval (CI). Variables which
yielded p-values of less than 0.2 in univariable logistic regression
were included in the final multivariable logistic regression model.
Results were presented as adjusted ORs (aORs) and 95% CIs. Statistical
analysis was conducted using STATA 16 software (StataCorp, College
Station, TX).