Maternal and Neonatal Outcomes of Placenta Previa with and without Coverage of a Uterine Scar: A Retrospective Cohort Study in a Tertiary Hospital

Prevalence of placenta previa among deliveries: An update systematic review and meta-analysis after the introduction of the two-child policy in Mainland China

Background

As birth policy can affect maternal and infant health, we sought to identify whether and how the introduction of the two-child policy might have affected the prevalence of placenta previa in pregnant women in mainland China.

Methods

In this update meta-analysis and systematic review, we searched PubMed, Web of Science, the Cochrane Library, Weipu, Wanfang, and the China National Knowledge Infrastructure (CNKI) databases for studies evaluating the prevalence of placenta previa in China published between the inception of each database and March 2024, with no restrictions. Two investigators independently extracted the data from each included study. We then combined the prevalence of placenta previa using random-effects models.

Results

We included 128 studies in our analysis, 48 more than in our previous review. The prevalence of placenta previa among Chinese pregnant women was 1.44% (95% confidence interval (CI) = 1.32, 1.56). After the implementation of the two-child policy, the prevalence increased significantly, from 1.25% (95% CI = 1.16, 1.34) to 4.12% (95% CI = 3.33, 4.91).

Conclusions

The prevalence of placenta previa increased significantly from the one-child policy period to the two-child policy period among mainland Chinese pregnant women, with varying trends across regions. This change requires the attention of health officials and timely adjustment of resource allocation policies.

Registration

PROSPERO: CRD42021262309.

Major placenta previa among patients with and without previous cesarean section: Maternal characteristics, outcomes and risk factors

OBJECTIVES

To compare maternal characteristics and outcomes among patients having major placenta previa (PP) with and without previous cesarean section (CS). And to determine if previous CS alone is a risk factor for associated adverse maternal outcomes in these patients.

MATERIALS AND METHODS

This is a retrospective analysis including two groups of major PP patients, with previous CS (n = 184) and without CS (n = 115); who were admitted to Abha Maternity and Children's Hospital over the last ten-years (January 2012-December 2021), Aseer region, Saudi Arabia.

RESULTS

Compared to those without previous CS, major PP patients with previous CS had significantly advanced ages with higher mean numbers of gravidity and parity, but significantly less rates of previous uterine surgery and IVF pregnancies. Moreover, they were more likely to acquire higher rates of adverse maternal outcomes. In the same way, these patients had an increased Odds Ratios of cesarean hysterectomy (OR of 20.462), urinary tract injuries (OR of 12.361), associated PAS (OR of 4.375), moderate/ heavy intra-operative bleeding (OR of 2.153) and the need for transfusion of 3+ units of packed RBCs (OR of 1.849).

CONCLUSION

(1) Patients with combined existence of major PP and previous CS had significantly higher rates of adverse maternal outcomes (2) Alone, prior CS in major PP patients increased the Odds Ratios of cesarean hysterectomy, urinary tract injuries, diagnosis of PAS, excessive intra-operative bleeding and repeated packed RBCs transfusions. (3) Among our PP patients with previous CS, the increased rate and OR of PAS diagnosis could in-part explain the adverse maternal outcomes.

Blood Type and Outcomes in Pregnant Women with Placenta Previa

Background

Placenta previa increases the risks of obstetrical complications. Many studies have reported a link between various ABO blood types and pregnancy complications. This study is aimed at describing and comparing the characteristics and outcomes of women with placenta previa by ABO blood type.

Methods

Data for this study was obtained from a retrospective cohort study between January 1, 2014, and June 30, 2019, of all clinically confirmed placenta previa in a university-based tertiary medical center. Both types of A, B, O, AB, and combining O and non-O blood types were compared to the characteristics and outcomes.

Results

1678 participants with placenta previa were included in this study. The highest participants were blood type O with 666 (39.7%), followed by type A with 508 (30.3%) and type B with 395 (23.5%), and the lowest participants were AB with 109 (6.5%). Blood type AB had a higher incidence of antepartum hemorrhage (p = 0.017), predelivery anemia (p = 0.036), and preterm birth (p = 0.015) in placenta previa women. Meanwhile, the incidence of rhesus D positive (97.9% vs. 95.8%, p = 0.012) and twins (5.0% vs. 2.7%, p = 0.011) was higher in the non-O group, and the incidence of neonatal asphyxia (5.9% vs. 9.2%, p = 0.016) was lower in the non-O group.

Conclusion

Type AB blood may be a potential risk factor for women with placenta previa. This finding may help provide any obstetrician to predict the risk of complication for placenta previa women by the ABO blood types.

Anesthetic management in cesarean delivery of women with placenta previa: a retrospective cohort study

Background

The incidence of placenta preiva is rising. Cesarean delivery is identified as the only safe and appropriate mode of delivery for pregnancies with placenta previa. Anesthesia is important during the cesarean delivery. The aim of this study is to assess maternal and neonatal outcomes of patients with placenta previa managed with neuraxial anesthesia as compared to those who underwent general anesthesia during cesarean delivery.

Methods

A retrospective cohort study was performed of all patients with placenta preiva at our large academic institution from January 1, 2014 to June 30, 2019. Patients were managed neuraxial anesthesia and general anesthesia during cesarean delivery.

Results

We identified 1234 patients with placenta previa who underwent cesarean delivery at our institution. Neuraxial anesthesia was performed in 737 (59.7%), and general anesthesia was completed in 497 (40.3%) patients. The mean estimated blood loss at neuraxial anesthesia of 558.96 ± 42.77 ml were significantly lower than the estimated blood loss at general anesthesia of 1952.51 ± 180 ml (p < 0.001). One hundred and forty-six of 737 (19.8%) patients required blood transfusion at neuraxial anesthesia, whereas 381 out of 497 (76.7%) patients required blood transfusion at general anesthesia. The rate neonatal asphyxia and admission to NICU at neuraxial anesthesia was significantly lower than general anesthesia (2.7% vs. 19.5 and 18.2% vs. 44.1%, respectively). After adjusting confounding factors, blood loss was less, Apgar score at 1- and 5-min were higher, and the rate of blood transfusion, neonatal asphyxia, and admission to NICU were lower in the neuraxial group.

Conclusions

Our data demonstrated that neuraxial anesthesia is associated with better maternal and neonatal outcomes during cesarean delivery in women with placenta previa.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01472-w.