A late-preterm, early-term stratified analysis of neonatal outcomes by gestational age in placenta previa: defining the optimal timing for delivery

Timing of cesarean delivery in women with uncomplicated placenta previa

OBJECTIVE

The optimal timing of an elective cesarean delivery for uncomplicated placenta previa remains controversial. Although the present guidelines recommend an elective cesarean delivery between 36^0/7 and 37^6/7weeks of gestation, data supporting this recommendation does not differentiate in outcomes between elective and emergent delivery, or between women with and without ante-partum hemorrhage. Recommendations regarding optimal timing of delivery are based on the risks and benefits associated with delivery at a certain gestational week, compared with a reference of 38 weeks. Therefore, the aim of this paper was to assess the maternal and neonatal adverse outcomes associated with elective delivery at different gestational weeks from 36^0/7 to 38^6/7weeks compared with expectant management in women with uncomplicated placenta previa.

METHODS

A retrospective cohort study in a single tertiary medical center of 251 women with a diagnosis of uncomplicated placenta previa, who delivered between 36^0/7 and 38^6/7weeks of gestation, who delivered at our center between Jan 2011 and Dec 2019. Maternal and neonatal outcomes at each gestational week were compared with expectant management.

RESULTS

At 36^0/7-36^6/7weeks, the rate of composite maternal adverse outcome was similar for elective delivery and expectant management (10.5% vs 7.7%, p = .68). Similarly, at 37^0/7-37^6/7 the rate of composite maternal adverse outcome was comparable for elective cesarean delivery and expectant management (7.2% vs 6.4%, p = .54). Maternal bleeding was the main indication of an urgent cesarean delivery, and account for 86% of urgent cesarean delivery at 36^0/7-36^6/7, 76.4% of urgent cesarean delivery at 37^0/7-37^6/7, and for 70.6% of all urgent cesarean delivery at 38^0/7-38^6/7weeks. This group of women who were delivered due to maternal bleeding had a history of maternal bleeding during 2nd and/or 3rd trimester in 75-92.3% of cases. Composite adverse neonatal outcome was similar for elective cesarean delivery at each gestational age compared with expectant management. The risk for lower 5-min APGAR score and hypoglycemia was higher for newborns that were delivered electively a 36th weeks of gestation compared with expectant management.

CONCLUSION

Our study suggests that the optimal time of delivery for women with an uncomplicated placenta previa is between 38^0/7 and 38^6/7weeks of gestation, especially in women without ante-partum bleeding.

Potential resolution of placenta previa from the 28th-to the 36th-week of pregnancy: A retrospective longitudinal cohort study

INTRODUCTION

Placenta previa greatly contributes to severe antenatal and post-partum hemorrhage. Previous studies have mainly focused on the risk factors of placenta previa, with very few studies reporting which factors may affect the potential resolution of 28th-week previa. This study aimed to investigate the impact of maternal characteristics on potential resolution of placenta previa from the 28th-to the 36th-week of pregnancy.

METHODS

A retrospective longitudinal sub-cohort investigation was carried out among 368 pregnant women with 28th-week previa from the Longitudinal Placenta Previa Study (LoPPS). Logistic regression analysis was used to discover the connections between maternal covariates and the placental potential resolution. Multivariable linear regression analysis was used to detect the associations between perioperative characteristics and volume of intraoperative bleeding.

RESULTS

Among pregnant women whose placenta completely or partially covered the internal os at the 28th-week of pregnancy, 37.5% were without placenta previa at the 36th-week and 25.8% converted into marginal placenta previa. There were significant correlation between placenta previa type and GHD (Beta: 2.808, 95% CI: 1.642, 7.138; p = 0.041), type of 28th-week previa (Beta: 6.767, 95% CI: 1.592, 18.767; p < 0.001), and number of prior cesarean sections (Beta: 3.326, 95% CI: 1.580, 9.081; p < 0.001).

DISCUSSION

62.5% of the pregnant women with 28th-week placenta previa were still with previa at the 36 weeks of gestation (25.8% with marginal and 36.7% with partial/complete placenta previa). This proportion is even higher for 28th-week complete placenta previa.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100054068, December 8, 2021.

Guideline No. 402: Diagnosis and Management of Placenta Previa

OBJECTIVES

To summarize the current evidence and to make recommendations for diagnosis and classification of placenta previa and for managing the care of women with this diagnosis.

OPTIONS

To manage in hospital or as an outpatient and to perform a cesarean delivery preterm or at term or to allow a trial of labour when a diagnosis of placenta previa or a low-lying placenta is suspected or confirmed.

OUTCOMES

Prolonged hospitalization, preterm birth, rate of cesarean delivery, maternal morbidity and mortality, and postnatal morbidity and mortality.

INTENDED USERS

Family physicians, obstetricians, midwives, and other maternal care providers.

TARGET POPULATION

Pregnant women with placenta previa or low-lying placenta.

EVIDENCE

Medline, PubMed, Embase, and the Cochrane Library were searched from inception to October 2018. Medical Subject Heading (MeSH) terms and key words related to pregnancy, placenta previa, low-lying placenta, antepartum hemorrhage, short cervical length, preterm labour, and cesarean. This document represents an abstraction of the evidence rather than a methodological review.

VALIDATION METHODS

This guideline has been reviewed by the Maternal-Fetal Medicine and Diagnostic Imaging committees of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and approved by the SOGC Board of Directors.

BENEFITS, HARMS, AND/OR COSTS

Women with placenta previa or low-lying placenta are at increased risk of maternal, fetal and postnatal adverse outcomes that include a potentially incorrect diagnosis and possibly unnecessary hospitalization, restriction of activities, early delivery, or cesarean delivery. Optimization of diagnosis and management protocols has potential to improve maternal, fetal and postnatal outcomes.

SUMMARY STATEMENTS (GRADE RATINGS IN PARENTHESES)

RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Management of pregnancy after fertility-sparing surgery for cervical cancer

Cervical cancer is increasingly diagnosed in women who have not yet completed their reproductive plans. For women with early-stage disease (FIGO stage IA1-IB1), fertility-sparing procedures, such as conization, trachelectomy or radical trachelectomy, represent the treatments of choice. However, women who undergo repeated conization or trachelectomy represent a challenge for obstetricians because they are at increased risk of infertility, mid-trimester miscarriage, preterm premature rupture of membranes and preterm delivery. So far, the evidence-based guidance on the management of these pregnancies is limited. This article reviews the literature discussing pregnancy management in women after fertility-sparing surgery for early cervical cancer. Although the evidence is limited, certain measures are desirable, including screening and treatment of asymptomatic bacteriuria, screening for cervical incompetence and progressive cervical shortening by transvaginal ultrasonography, and fetal fibronectin testing. Vaginal progesterone supplementation should be primary prevention for all women after trachelectomy. Women with a history of preterm delivery or late miscarriage may benefit from cervical cerclage. Elective delivery by cesarean section in the early-term period is desirable.