Impact of placenta previa with placenta accreta spectrum disorder on fetal growth

Abstract

Objectives To evaluate fetal growth in pregnancies complicated by placenta previa with or without placenta accreta spectrum (PAS) disorder, compared with in pregnancies with a low‐lying placenta. Methods This was a multicenter retrospective cohort study of singleton pregnancies complicated by placenta previa with or without PAS disorder, for which maternal characteristics, ultrasound‐estimated fetal weight and birth weight were available. Four maternal–fetal medicine units participated in data collection of diagnosis, treatment and outcome. The control group comprised singleton pregnancies with a low‐lying placenta (0.5–2 cm from the internal os). The diagnosis of PAS and depth of invasion were confirmed at delivery using both a predefined clinical grading score and histopathological examination. For comparison of pregnancy characteristics and fetal growth parameters, the study groups were matched for smoking status, ethnic origin, fetal sex and gestational age at delivery. Results The study included 82 women with placenta previa with PAS disorder, subdivided into adherent (n = 35) and invasive (n = 47) PAS subgroups, and 146 women with placenta previa without PAS disorder. There were 64 controls with a low‐lying placenta. There was no significant difference in the incidence of small‐for‐gestational age (SGA) (birth weight ≤ 10th percentile) and large‐for‐gestational age (LGA) (birth weight ≥ 90th percentile) between the study groups. Median gestational age at diagnosis was significantly lower in pregnancies with placenta previa without PAS disorder than in the low‐lying placenta group (P = 0.002). No significant difference was found between pregnancies complicated by placenta previa with PAS disorder and those without for any of the variables. Median estimated fetal weight percentile was significantly lower in the adherent compared with the invasive previa–PAS subgroup (P = 0.047). Actual birth weight percentile at delivery did not differ significantly between the subgroups (P = 0.804). Conclusions No difference was seen in fetal growth in pregnancies complicated by placenta previa with PAS disorder compared with those without and compared with those with a low‐lying placenta. There was also no increased incidence of either SGA or LGA neonates in pregnancies with placenta previa and PAS disorder compared with those with placenta previa with spontaneous separation of the placenta at birth. Adverse neonatal outcome in pregnancies complicated by placenta previa and PAS disorder is linked to premature delivery and not to impaired fetal growth. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Placental Implantation Disorders

“…low-lying placenta (partial previa) and placenta previa (marginal or complete) did not impact the risk of FGR. These data and our recent study showing no difference in the rate of FGR in both low-lying and placenta previa [31] suggest that implantation in the lower uterine segment does not affect the normal development of the uteroplacental circulation and/or normal placental functions.…”

“…The pathological and phenotypic changes are hard to define as the normal vascular architecture of the placental bed may be distorted in the scar area. Furthermore, these changes in remodelling of the utero-placental circulation in placenta accreta are not associated with any impact on placental or fetal growth, nor on the incidence of pre-eclampsia [31].…”

Effect of previous placenta previa on outcome of next pregnancy: a 10-year retrospective cohort study

“…A meta-analysis showed that placenta previa was associated with a mild increase in the risk of intrauterine growth restriction [29]. Jauniaux et al found no difference in fetal growth between women with placenta previa and PAS disorders and women with placenta previa only [30]. The effects of placenta previa on the neonatal outcomes in subsequent pregnancies have seldom been reported.…”

Investigating Outcome and Risk Factors of Placenta Previa and Placental Abruption in Pregnant Women Referred to Ali Ibn Abitalib Hospital in Zahedan

“…Other studies including Moradan et al (2018) and Barzegar Jalali (2016) have also been consistent with our study (22,23) but in some studies, different findings have been reported and a significant relationship between cesarean and placenta previa history was not reported (24,25). Many studies have indicated the presence of risk factors and demographic characteristics associated with placenta previa or placental abruption that the role of risk factors in the identification and reduction of complications have been highlighted (26)(27)(28).…”