Clinical profiles of placenta accreta spectrum: the PACCRETA population‐based study

Abstract

Objective To describe and compare the characteristics of women with placenta accreta spectrum (PAS) and their pregnancy outcomes according to the presence of placenta praevia and a prior caesarean section. Design Prospective population‐based study. Setting All 176 maternity hospitals of eight French regions. Population Two hundred and forty‐nine women with PAS, from a source population of 520 114 deliveries. Methods Women with PAS were classified into two risk‐profile groups, with or without the high‐risk combination of placenta praevia (or an anterior low‐lying placenta) and at least one prior caesarean. These two groups were described and compared. Main outcome measures Population‐based incidence of PAS, characteristics of women, pregnancies, deliveries and pregnancy outcomes. Results The PAS population‐based incidence was 4.8/10 000 (95% CI 4.2–5.4/10 000). After exclusion of women lost to follow up from the analysis, the group with placenta praevia and a prior caesarean included 115 (48%) women and the group without this combination included 127 (52%). In the group with both factors, PAS was more often suspected antenatally (77% versus 17%; P < 0.001) and more often percreta (38% versus 5%; P < 0.001). This group also had more hysterectomies (53% versus 21%, P < 0.001) and higher rates of blood product transfusions, maternal complications, preterm births and neonatal intensive care unit admissions. Sensitivity analysis showed similar results after exclusion of women who delivered vaginally. Conclusion More than half the cases of PAS occurred in women without the combination of placenta praevia and a prior caesarean delivery, and these women had better maternal and neonatal outcomes. We cannot completely rule out that some of the women who delivered vaginally had placental retention rather than PAS; however, we found similar results among women who delivered by caesarean. Tweetable abstract Half the women with PAS do not have both placenta praevia and a prior caesarean delivery, and they have better maternal outcomes.

Characteristics and outcomes of pregnant women with placenta accreta spectrum in Italy: A prospective population-based cohort study

“…Rate of maternal death in our study (2.6‰, national rate 0.09‰ [ 25 ]), was higher compared to the UKOSS, NOSS, and Australian cohorts, which did not report any fatal case [ 16 , 34 , 36 ], but lower than the French cohort (4.1‰) [ 38 ]. Of note, the only death in our cohort occurred in an unsuspected woman without risk factors for PAS.…”

“…However, a lower rate of PAS (0.46‰) was still identified when these women were included in a previous analysis [ 32 ], thus suggesting a more relevant role of prior CS rate (10% in Nordic countries vs 16.8% in Italy) in causing such a difference [ 20 , 36 ]. Similarly, the higher rate of prior CS might explain the increased PAS prevalence in Italy compared to France (0.48‰, prior CS rate 11.4%) [ 38 ] and to the United Kingdom (0.17‰, prior CS rate 14.9%) [ 34 ]. In turn, the use of statistic record-linkage procedures instead of active reporting may account for our lower prevalence estimates compared to a recent Australian-population based study (2.5‰, prior CS rate 14.4%) [ 16 ].…”

“…Of note, there were 25 (6.5%) women with both placenta previa or low-lying and prior CS, a combination of risk factors defining a clinical profile at high risk for adverse outcomes [ 38 ], who were not antenatally suspected. Knowledge of relevant risk factors for PAS is pivotal to guide a targeted prenatal ultrasound scan and increase the rate of antenatal diagnosis [ 42 , 47 – 55 ].…”

“…Almost half of our patients had a high-risk clinical profile [ 38 ]. Although such profile was substantially more common among women in the South compared to the North, we observed improved outcomes with decreased rates of PPH, blood transfusion, ICU admission, and severe maternal morbidity.…”

“…Although such profile was substantially more common among women in the South compared to the North, we observed improved outcomes with decreased rates of PPH, blood transfusion, ICU admission, and severe maternal morbidity. Also, these women less frequently experienced intra- and post-hysterectomy complications, notwithstanding higher rates of placenta previa and previous CS, conditions known to make surgery more technically challenging [ 38 , 44 , 56 , 57 ]. Since referral of expected cases has been suggested as a more important determinant of outcomes than the patient’s clinical risk profile [ 45 , 53 , 58 ], it is plausible that this finding may be related to the higher rate of antenatal diagnosis observed among Southern women (61.7% vs 28.7%) with their subsequent referral to specialized centers, which occurred in 71.9% of the cases.…”