The epidemiology of placenta previa in the United States, 1979 through 1987

Impact of Pelvic Rest Recommendations on Follow-Up and Resolution of Placenta Previa and Low-Lying Placenta

OBJECTIVE

To determine the rate of resolution of placenta previa and low-lying placenta (LLP) and the effect of pelvic rest recommendations on the timing of follow-up imaging.

METHODS

Retrospective review of pregnancies with previa/LLP detected on mid-trimester exam at our ultrasound unit from 2019 to 2021. LLP was defined as the lower edge of placenta located within 2 cm of the internal cervical os. Previa was defined as any portion of the placenta touching with the internal os. Demographics, placental location, activity restrictions, and delivery outcomes were analyzed. Timing of follow-up imaging was stratified by individuals advised and not advised pelvic rest.

RESULTS

Exactly 144 patients had previa and 266 had LLP on the mid-trimester exam with complete records. Previa resolution happened in 51.4% (74/144) of cases. Exactly 62% (46/74) of previa resolutions occurred by the 28-week ultrasound. Exactly 45% (65/144) of previa patients were advised pelvic rest. Most pelvic rest and non-pelvic rest patients had a 28-week scan. Even when clearance occurred, most patients in both groups had a repeat ultrasound at 32 weeks. Exactly 75% of LLP resolved by the 28-week scan, and the remainder by delivery. Exactly 12% (32/259) of LLP patients were advised pelvic rest.

CONCLUSION

Most societies recommend follow-up imaging at 32 weeks; however, our results suggest this may be done sooner and closer to 28 weeks. Pelvic rest did not affect timing of repeat imaging or 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.

Prevalence and Fetomaternal Outcome of Placenta Previa at Salmaniya Medical Complex, Bahrain

Background

Placenta previa is a condition which occurs when the placenta implants in the lower uterine segment, thus obstructing delivery. It is considered a grave pregnancy complication as it is associated with massive maternal hemorrhage. The condition is associated with previous cesarean delivery, multiple gestations, and increased maternal age. The placental villi may abnormally adhere, invade, or penetrate the myometrium causing accreta, increta, or percreta, respectively. It is the most common indication of peripartum hysterectomy. The gold standard for diagnosis of placenta previa is transvaginal ultrasound. 

Objective

This study aims to calculate the prevalence of placenta previa in relation to the known risk factors and to determine the fetomaternal outcome which will aid in improving the obstetric care of patients with placenta previa. 

Methods

A total of 216 placenta previa cases diagnosed between October 2014 and December 2018 were evaluated in a retrospective cross-sectional study. Analysis of the data was conducted using SPSS software, version 20 (IBM Corp., Armonk, NY).

Results

The total number of deliveries during the study period was 25,693 out of which 216 were diagnosed with placenta previa. Thus, the prevalence of placenta previa is 0.84%. The mean age at diagnosis was 32.8 years. At diagnosis, 23.1% of the cases were primiparous. Of the 216 patients, 1.9% were diagnosed with placenta percreta, of which 5.1% received a hysterectomy; 59.7% had uncomplicated elective cesarean delivery at 37-38 weeks of gestation. The mean gestational age at emergency delivery was 35.97 (+-3.1).

Conclusion

The study highlights that although risk factors increase the likelihood of placenta previa, it is necessary to rule it out in women with no known risk factors.

Placental thickness correlates with placenta accreta spectrum (PAS) disorder in women with placenta previa

OBJECTIVE

To evaluate the association of placental thickness with placenta accreta spectrum disorder in placenta previa.

METHODS

In this IRB-approved, retrospective study, ultrasound (US) reports were retrospectively queried for keyword previa. US performed closest to mid-gestation were included. Three measurements were performed at the thickest portion of the placenta on longitudinal transabdominal images. Operative reports and surgical pathology were used as the reference standard. Statistical analysis was performed using unpaired T-tests and receiver operating curve (ROC) analysis.

RESULTS

Sixty-five patients with placenta previa were included: 38 with PAS disorder and 27 without PAS disorder, clinically or pathologically. 38/38 (100%) patients of PAS group and 16/27 (59.3%) patients of non-PAS group had history of prior cesarean section. The average placental thickness was 4.3 cm (range 1.8 cm to 7.8 cm) for PAS group and 3.0 cm (range 0.6 cm to 5.3 cm) for non-PAS group (p < 0.001). Placental thickness in patients without PAS disorder and history of prior cesarean section was 3.1 (± 1.1) cm. This was statistically different from patients who had history of prior cesarean section with PAS diagnosis (4.3 cm, P<0.01). Using ROC analysis, a threshold measurement of 4.5 cm leads to sensitivity of 50% and specificity of 96%.

CONCLUSION

Our results demonstrate that among women with placenta previa, increased placental thickness at lower uterine segment correlates with placenta accreta spectrum disorder. A threshold of 4.5 cm can be useful for screening patients with placenta previa and risks factors for PAS.

Fetal and Maternal Outcomes in Women With Major Placenta Previa Among Sudanese Women: A Prospective Cross-Sectional Study

Background

Placenta previa is a major obstetric problem with high rates of fetomaternal mortality and morbidity. This study aimed to determine the prevalence and fetal and maternal outcomes of major degree placenta previa among Sudanese women.

Method

This is a prospective descriptive study conducted in the period from January 1 to June 30, 2109, at Omdurman Maternity Hospital, Khartoum, Sudan. Fetal and maternal complications associated with major degree placenta were analyzed using descriptive statistics.

Results

The total number of deliveries was 22,000, of which 87 cases were of major degree placenta previa, giving a prevalence rate of 0.4%, the hysterectomies rate was 23% (n= 20), and the total maternal deaths were 6.9% (n= 6). Intraoperative interventions used to control the bleeding were multiple hemostatic sutures in 34.5% (n=30) of cases, followed by uterine backing (20.7%; n= 18), and uterine artery ligation (12.6%; n=11). The common reported maternal complications were bladder injuries (28.7%; n= 25) followed by bowel injuries (4.6%; n=5). Of all mothers, 48.27% (n=42) were admitted to the intensive care unit (ICU). Of all deliveries, 26.4% (n=23) were preterm, and 38% (n=33) of neonates were admitted to the newborn intensive care unit (NICU), and 9.2% (n=8) were fresh stillbirth (FSB).

Conclusion

Neonatal complications were comparable to other studies but maternal deaths were relatively high. The study indicated the need for effective management protocols and more training of the medical staff in order to overcome the problem.

Predictors of adverse neonatal outcome in pregnancies complicated by placenta previa

INTRODUCTION

We aimed to underline the determinants of adverse neonatal outcome in gestations complicated by placenta previa (PP).

METHODS

A retrospective study including all women diagnosed with placenta previa carrying a singleton gestation who delivered between 2011 and June 2019. Gestations with adverse neonatal outcomes were compared to those without. In a secondary analysis, we further studied the rate of Placenta accreta spectrum (PAS) in relation to number of previous cesarean deliveries.

RESULTS

Overall, 548/84,558 (0.6%) singleton deliveries were complicated by PP (0.6%). PAS was noted in 105 (19.2%) cases. After exclusion of PAS cases, adverse neonatal outcome occurred in 149/443 (33.6%), median gestational age of delivery was 37 ^0/7 with a median birthweight of 2780 g. In a univariate analysis, adverse neonatal outcome was associated with emergent delivery and general anesthesia [56.8% vs. 20.8%, OR 5.00 (95% CI) 3.24-7.72, p < 0.001 and 54.4% vs. 24.8%, OR 3.60 (95% CI) 2.37-5.47, p < 0.001, respectively]. Gestational age at delivery was lower in the adverse outcome group (mean 35 ^1/7 vs. 37 ^3/7, p < 0.001). In a multivariate regression analysis, general anesthesia and gestational age at delivery were independently associated with adverse neonatal outcome [adjusted odds ratio (aOR) 2.26 (95% CI) 1.18-4.31, p = 0.01, aOR 1.10 (95% CI) 1.05-1.16, p < 0.001. Analysis of the rate of PAS among women with previous cesarean delivery and PP revealed that no cases of PAS were noted when no prior cesarean delivery was present. The rate of PAS for previous 1, 2, 3, 4 and 5 cesarean deliveries was 26.7%, 43.5%, 65.5%, 55.6% and 66.7% respectively.

DISCUSSION

Efforts should be made to avoid general anesthesia in deliveries of PP.

Follow-up ultrasound in second-trimester low-positioned anterior and posterior placentae: prospective cohort study

OBJECTIVES

The majority of cases of placenta previa or a low-lying placenta in the second trimester will have a normal placental position in the third trimester. The aim of this study was to assess the accuracy of the distance between the placenta and the internal os of the cervix (IOD) in the second trimester for the prediction of third-trimester low-positioned placenta, and to define a cut-off value at which all cases of third-trimester low-positioned placenta are identified.

METHODS

This was a prospective cohort study including women undergoing a transvaginal ultrasound examination between 18 and 24 weeks' gestation who had a low-positioned placenta, defined as an IOD of < 20 mm. Low-positioned placenta included placenta previa, defined as a placenta covering the internal os of the cervix, and a low-lying placenta, defined as a placenta lying near to (within 20 mm) but not overlying the internal os. All women were re-evaluated in the third trimester. Relative risks for a low-positioned placenta in the third trimester were calculated for women with placenta previa vs a low-lying placenta, posterior vs anterior placenta and positive vs negative history of Cesarean section. Multilevel likelihood ratios for ranges of IOD in the prediction of a low-positioned placenta in the third trimester were calculated separately for anteriorly and posteriorly located placentae. Corresponding receiver-operating-characteristics curves were constructed.

RESULTS

In total, 958 women were included in the study. In the second trimester, placentae were more frequently located on the posterior side (62.0%) than on the anterior side (38.0%). In the third trimester, 48/958 (5.0%) placentae persisted as a low-positioned placenta. Women with placenta previa in the second trimester had a higher risk of a low-positioned placenta in the third trimester than did those with a low-lying placenta in the second trimester (37/181 (20.4%) vs 11/777 (1.4%); relative risk (RR), 17.9 (95% CI, 8.9-36.0)). Women with a posterior placenta had a higher risk of a low-positioned placenta in the third trimester than did those with an anterior placenta (38/594 (6.4%) vs 10/364 (2.7%); RR, 2.4 (95% CI, 1.2-4.9)), as did women with a history of Cesarean section compared with those without such a history (14/105 (13.3%) vs 34/853 (4.0%); RR, 3.7 (95% CI, 1.9-7.2)). The cut-off value of IOD in the second trimester to identify all cases of an abnormally located placenta in the third trimester was 15.5 mm for posteriorly located placentae, while for anteriorly located placentae the IOD cut-off was lower, namely -4.5 mm, representing a 4.5-mm overlap of the placental edge over the internal os of the cervix.

CONCLUSIONS

With incorporation of a safety margin of 5 mm and ensuring that all women with placenta previa undergo a follow-up scan, we recommend lowering the IOD cut-off value for follow-up in cases of an anterior low-positioned placenta from 20 to 5 mm, which would decrease the number of unnecessary follow-up ultrasound examinations without missing any high-risk women. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Maternal risk factors associated with persistent placenta previa

INTRODUCTION

Maternal risk factors associated with placenta previa are well documented in the literature. However, there are limited studies identifying maternal characteristics associated with the persistence of placenta previa. The objective of the study was to determine maternal characteristics associated with the persistent placenta previa.

METHODS

A retrospective cohort study was conducted in which 705 pregnant women diagnosed with low-lying placenta or placenta previa between 17 and 24 weeks gestation were identified from a single institution between 2003 and 2017. The primary outcome included persistent placenta previa (i.e., persistent placental tissue within 2 cm of the internal os) at or after 36 weeks 0 days. Those with abnormal placentation (e.g., vasa previa, placenta accreta) or delivery prior to 36 weeks 0 days were excluded. Multivariable logistic regression modeling was utilized to determine significant maternal characteristics associated with persistent placenta previa among women diagnosed with either placenta previa or low-lying placenta.

RESULTS

Women with a prior cesarean delivery were seven times more likely to have persistent placenta previa (odds ratio, 7.0, 95% confidence interval, 3.7-13.1). A history of intrauterine curettage or evacuation in the setting of placenta previa increases the likelihood of persistent placenta previa almost 3-fold (odds ratio, 2.5, 95% confidence interval, 1.3-5.0).

DISCUSSION

To date, our study is the largest, retrospective cohort study assessing maternal risk factors associated with persistent placenta previa; and is the first to detect a statistically significant correlation between a history of intrauterine surgeries and persistent placenta previa.

Cervical Pessary versus Expectant Management for the Prevention of Delivery Prior to 36 Weeks in Women with Placenta Previa: A Randomized Controlled Trial

Objective  This multicenter randomized controlled trial compared cervical pessary (CP) versus expectant management (EM) in women with placenta previa between 22.0 and 32.0 in prolonging gestation until ≥ 36.0 weeks' gestation. Study Design  This study took place from November 2016 to June 2018. Women were randomized to receive either the Bioteque CP or EM. The pessary was removed at ≥ 36.0 weeks unless indicated. The primary outcome was gestational age (GA) at delivery, with secondary outcomes including need for transfusion, number and duration of antepartum admissions, type of delivery, and neonatal outcomes. A total of 140 patients were needed to show a 3-week prolongation of pregnancy in the pessary group; however, the trial was stopped early due to budgetary issues. Results  Of the 33 eligible women, 17 were enrolled. Although not statistically significant, the mean GA at delivery in the CP group was greater than women in the EM group (36.5 ± 1.23 vs. 36.0 ± 2.0; p  = 0.1673). The number and duration of antepartum admissions was greater in the EM group (2.7 ± 0.58 vs. 16.0 ± 22.76 days; p  = 0.1264) as well. Conclusion  Although the study was underpowered to determine the primary outcome, safety and feasibility of CP in pregnancies complicated with previa were demonstrated.

Using tocolysis in pregnant women with symptomatic placenta praevia does not significantly improve prenatal, perinatal, neonatal and maternal outcomes: a systematic review and meta-analysis

BACKGROUND

Placenta praevia refers to a placenta located in the lower segment of the uterus. This abnormal location predisposes the placenta to abnormal bleeding with an increased risk of premature labour. The merits of tocolytic drugs (tocolysis) to calm uterine contractions and prolong pregnancy in women with placenta praevia are uncertain.

OBJECTIVES

The primary objective is to determine the effects of tocolysis versus no tocolysis on pregnancy prolongation. Secondary objectives include to determining the effects of tocolysis versus no tocolysis on gestational age at delivery, maternal hospitalisations, recurrent vaginal bleeding, prematurity, admissions into neonatology, and perinatal deaths.

METHODS

We searched MEDLINE, EMBASE, The Cochrane Central Register of Controlled Trials, reference lists of pertinent articles and trial registries for randomised controlled trials comparing tocolysis to no tocolysis or placebo in patients with placenta praevia. Risk of bias and data extraction was done independently by two reviewers. We pooled data using a random-effects model. We used the GRADE system to assess the certainty of evidence for each outcome.

MAIN RESULTS

There is no significant difference in pregnancy prolongation with the use of tocolysis in cases of placenta praevia (mean difference [MD] 11.51 days; 95% CI, - 1.75, 24.76; 3 trials, 253 participants; low certainty evidence). Tocolysis has no significant effect on gestational age at delivery (MD 0.33 weeks [95% CI - 1.53, 2.19]: 2 trials, 169 participants, moderate certainty evidence), birthweight (MD 0.12 kg [95% CI - 0.26, 0.5 kg]: 2 trials, 169 participants, moderate certainty evidence), risk of premature delivery (risk ratio [RR] 1.04; 95% CI 0.56, 1.94): 2 trials, 169 participants, low certainty evidence), risk of repeat vaginal bleeding (RR 1.05 [95% CI 0.73, 1.51]: 2 trials, 169 participants, moderate certainty evidence). Tocolysis has no significant effect on the risk of perinatal death (risk difference [RD]: 0.00 [95% CI - 0.04, 0.03]: 2 trials, 169 women; low certainty evidence), number of days of maternal hospitalisation (MD 0.60 days [95% CI - 0.79, 1.99]: 1 trial, 109 women; low certainty evidence), risk of fetal admissions into neonatology (RR 1.30 [95% CI 0.80, 2.12]: 1 trial, 109 participants, low certainty evidence) and on the duration of stay in neonatology units (MD 0.70 days [95% CI - 5.26, 6.66]: 1 trial, 109 participants, low certainty evidence).

CONCLUSION

In women with symptomatic placenta praevia, there is no significant effect on pregnancy prolongation with the use of tocolysis. Tocolysis has no significant effect on other prenatal, perinatal, neonatal and maternal outcomes among women with symptomatic placenta praevia.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018091513.

Progressive Devascularization: A Novel Surgical Approach for Placenta Previa

Background  The gold standard for antenatal diagnosis of placenta previa is the transvaginal ultrasonography. In placenta previa cases, separation of placental and uterine tissues is challenging even for the most experienced surgeons. Life-threatening obstetrical complications from cesarean deliveries with placenta previa include peripartum hemorrhage, coagulopathy, blood transfusion, peripartum hysterectomy, and multiple organ failure. Cases  We detailed the 3 cases of placenta previa that underwent bilateral uterine artery ligation; if hemostasis was not achieved, horizontal mattress sutures were placed in the lower uterine segment. All patients were discharged with minimal morbidity. Conclusion  For patients with placenta previa and low risk for placenta creta, counseling should include the risk for maternal morbidity and criteria for pursuing peripartum hysterectomy. Our devascularization, a stepwise surgical approach, shows promising outcomes in placenta previa cases. Précis  We propose a novel surgical approach, using a progressive devascularization surgical technique, for management of women with placenta previa, undergoing cesarean delivery.

Women with Endometriosis, Especially Those Who Conceived with Assisted Reproductive Technology, Have Increased Risk of Placenta Previa: Meta-analyses

BACKGROUND

Many women with endometriosis have become pregnant through assisted reproductive technology (ART), and have often experienced placenta previa (PP) during pregnancy. The objective of this study was to assess the association between women with endometriosis, especially those who conceived with ART, and the risk of PP.

METHODS

Two reviewers independently determined studies that were considered suitable for meta-analyses published in various medicine-related databases from March 1, 2004 through July 31, 2017 without language restrictions. Eight studies met the inclusion criteria, with a combined sample size of 21,930 women. Of these 21,930 pregnancies, 6,256 had endometriosis (endometriosis) and 15,674 had no endometriosis. Four of these studies included 8,161 women who conceived with ART, 1,640 of whom had endometriosis (endometriosis + ART), and 6,521 of whom did not have endometriosis. Meta-analyses were estimated with odds ratios (ORs) and 95% confidence intervals (CIs) using random effect analysis according to heterogeneity of studies.

RESULTS

These meta-analyses showed women with endometriosis (endometriosis) have an increased risk of PP (OR, 4.038; 95% CI, 2.291-7.116; P = 0.000). These results showed women who conceived with ART (endometriosis + ART), have a substantially increased risk of PP (OR, 5.543; 95% CI, 1.659-18.523; P = 0.005).

CONCLUSION

These meta-analyses demonstrate women with endometriosis have an increased risk of PP.

The effect of advanced maternal age on maternal and neonatal outcomes of placenta previa: A register-based cohort study

OBJECTIVES

Advanced maternal age (AMA) at the time of delivery generally worsens obstetric outcomes, but its effects on specific pregnancy problems, such as placenta previa, have not been adequately assessed. Therefore, the objective of the study was to explore the effect of AMA on adverse maternal and neonatal outcomes among pregnancies complicated by placenta previa.

STUDY DESIGN

The study was a register-based cohort study using data of three Finnish health registries, including information of 283 324 women and their newborns. Separate multivariable logistic regression modeling was performed for women under age 35 and women aged 35 or older to assess the association between placenta previa and adverse maternal and neonatal outcomes. Furthermore, interactions between maternal age and placenta previa were tested.

RESULTS

A total of 283 324 deliveries of which 714 (0.3%) were complicated by placenta previa. Adverse maternal and neonatal outcomes increased in women with placenta previa, with different patterns across age groups. The adjusted odds ratios and 95% confidence intervals for AMA and young women with previa were 7.3 (5.0-10.6) and 6.8 (5.2-8.9) in blood transfusion, 11.3 (5.4-23.3) and 10.9 (6.1-19.6) in placental abruption. In neonatal outcomes the adjusted odds ratios for AMA and young women with placenta previa were 8.8 (6.6-11.6) and 11.7 (9.7-14.1) in preterm birth <37 weeks, 4.0 (3.0-5.3) and 4.9 (4.1-5.9) in neonatal intensive care unit (NICU) admission, 4.0 (2.8-5.7) and 5.9 (4.7-7.4) low birth weight <2500 g, 2.7 (1.5-4.9) and 3.3 (2.2-5.0) in low Apgar score at 5 min. The joint effects of maternal age and placenta previa on the risk of adverse maternal and neonatal outcomes were non-significant.

CONCLUSIONS

The risk of adverse maternal and neonatal outcomes for women with placenta previa was not substantially affected by maternal age if their different risk profiles were taken into account.

Parental ethnicity and placental maternal vascular malperfusion pathology in healthy nulliparous women

INTRODUCTION

Rates of some placental-associated pregnancy complications vary by ethnicity, though the strength of association with underlying placental pathology is presently unknown. Our objective was to determine whether an association between ethnicity and placental pathology occurs in low-risk pregnancies.

METHODS

829 low-risk nulliparous pregnant women were prospectively studied. Data were obtained from standardized obstetrical appointments (clinical history, serum biomarkers, placental ultrasound) and hospital delivery records (pregnancy complications, delivery details and perinatal outcomes). Placental pathology was performed in all subjects using standard criteria.

RESULTS

In our cohort, 72% of women were Caucasian, 14% East Asian, 8% South Asian, 4% Afro-Caribbean and 3% Hispanic women. 81% of couples were concordant (same ethnic background) and 19% discordant (mixed ethnicities). South Asian women had the highest rate of small for gestational age (SGA) birth (customized birthweight <10th percentile) (24.2%), which was associated with the placental features of uteroplacental vascular insufficiency (placental weight <10th percentile with decidual vasculopathy, focal infarction, and/or syncytial knot formation) (p = 0.05). Placental efficiency varied significantly by ethnicity; Caucasian women had the highest efficiency (7.1 ± 1.2) and Afro-Caribbean women the lowest (6.5 ± 0.9) (p < 0.003). Afro-Caribbean women had the highest rate of marginal cord insertion. Placental efficiency, was higher in concordant vs. discordant couples (7.0 ± 1.2 vs. 6.8 ± 1.1; p < 0.05). Placental histopathology was not affected by parental ethnic discordance.

DISCUSSION

Maternal ethnicity influences placental efficiency and relationship between uteroplacental vascular insufficiency and SGA birth, but was not associated with other placental pathologies. Discordant parental ethnicity did not affect the development of placental pathologies or adverse pregnancy outcomes.

Complete Placenta Previa: Ultrasound Biometry and Surgical Outcomes

Objective  To evaluate the relationship between surgical outcomes and ultrasound measurement of placental extension beyond the cervical os in women with placenta previa. Study Design  This is a retrospective cohort study of singleton pregnancies with placenta previa undergoing third-trimester ultrasound and delivering at our institution from 2002 through 2011. For study purposes, an investigator measured placental extension, defined as the placental distance from the internal os across the placenta continuing out to the lowest placental edge. If morbidly adherent placentation was suspected, women were excluded. Receiver operating characteristic (ROC) curves were developed for pertinent surgical outcomes, and multivariate analysis was performed to determine the placental extension with the best predictive discriminatory zone. Results  In total, 157 women had placenta previa, ultrasound, and delivery data: 86 (55%) had a placental extension of <40 mm, and 71 (45%) had a placental extension of ≥40 mm. Women with placental extension of ≥40 mm had increased surgical time, blood loss > 2,000 mL, blood transfusion, and rate of peripartum hysterectomy. After multivariate analysis, only peripartum hysterectomy and surgical time > 90 minutes remained significant, p ≤ 0.05 and p ≤ 0.01, respectively. Conclusion  In women with placenta previa, the placental extension ultrasound measurement of ≥40 mm is a predictor of adverse surgical outcomes.

Association of Placenta Previa with a History of Previous Cesarian Deliveries and Indications for a Possible Role of a Genetic Component

A prior Cesaria section (C-section) is an important risk factor that leads to endometrial damage and abnormal implantation of the placenta. Our retrospective study aims to correlate the frequency of placenta previa to previous C-sections, to determine the effect of male gender in this condition and to evaluate further the maternal outcome. Seventy-six cases with placenta previa were selected out of 5200 live births. Diagnosis was confirmed by ultrasound and in the operating theater. In the 76 women examined, we found 50 cases with a history of a previous C-section (66.0%) and 49 male offspring (65.0%) (p <0.001), with a mean birth weight of 2635 ± 740 g. Of all these patients, six (8.0%) cases developed placenta percreta, seven (9.0%) were transferred to the intensive care unit (ICU), 14 (18.0%) women needed blood transfusion and eight (11.0%) underwent hysterectomy. The results of our series show a strong correlation of placenta previa to a history of previous C-sections and a predominance of male fetuses. Early recognition and proper monitoring could minimize the possibility of a poor outcome.

Maintenance nifedipine therapy for preterm symptomatic placenta previa: A randomized, multicenter, double-blind, placebo-controlled trial

Objective

To assess the impact of maintenance nifedipine therapy on pregnancy duration in women with preterm placenta previa bleeding.

Methods

PPADAL was a randomized, double-blind, placebo-controlled trial conducted between 05/2008 and 05/2012 in five French hospitals. The trial included 109 women, aged ≥ 18 years, with at least one episode of placenta previa bleeding, intact membranes and no other pregnancy complication, at gestational age 24 to 34 weeks and after 48 hours of complete acute tocolysis. Women were randomly allocated to receive either 20 mg of slow-release nifedipine three times daily (n = 54) or placebo (n = 55) until 36 + 6 weeks of gestation. The primary outcome for the trial was length of pregnancy measured in days after enrolment. Main secondary outcomes were rates of recurrent bleeding, cesarean delivery due to hemorrhage, blood transfusion, maternal side effects, gestational age at delivery and adverse perinatal outcomes (perinatal death, chronic lung disease, neonatal sepsis, intraventricular hemorrhage > grade 2, perventricular leukomalacia > grade 1, or necrotizing enterocolitis). Analysis was by intention to treat.

Results

Mean (SD) prolongation of pregnancy was not different between the nifedipine (n = 54) and the placebo (n = 55) group; 42.5 days ± 23.8 versus 44.2 days ± 24.5, p = 0.70. Cesarean due to hemorrhage performed before 37 weeks occurred more frequently in the nifedipine group in comparison with the placebo group (RR, 1.66; 95% confidence interval, 1.05–2.72). Adverse perinatal outcomes were comparable between groups; 3.8% for nifedipine versus 5.5% for placebo (relative risk, 0.52; 95% confidence interval 0.10–2.61). No maternal mortality or perinatal death occurred.

Conclusion

Maintenance oral nifedipine neither prolongs duration of pregnancy nor improves maternal or perinatal outcomes.

Trial registration

ClinicalTrials.gov NCT00620724

Identification and Management of Obstetric Hemorrhage

Obstetric hemorrhage remains the leading cause of maternal death and severe morbidity worldwide. Although uterine atony is the most common cause of peripartum bleeding, abnormal placentation, coagulation disorders, and genital tract trauma contribute to adverse maternal outcomes. Given the inability to reliably predict patients at high risk for obstetric hemorrhage, all parturients should be considered susceptible, and extreme vigilance must be exercised in the assessment of blood loss and hemodynamic stability during the peripartum period. Obstetric-specific hemorrhage protocols, facilitating the integration and timely escalation of pharmacologic, radiological, surgical, and transfusion interventions, are critical to the successful management of peripartum bleeding.

Brief communication (Original). Anesthesia for cesarean section in parturients diagnosed with placenta previa in a Thai university hospital: a retrospective analysis of 562 consecutive cases

Background: Anesthesia for cesarean delivery in parturients diagnosed with placenta previa remains controversial.

Objectives: To investigate factors correlated with choice of anesthesia in these parturients and their outcomes.

Methods: Retrospective analysis of patients with placenta previa and cesarean delivery at King Chulalongkorn Memorial Hospital. Peri operative anesthetic and complication data were collected using a structured collection form. Univariate analysis and multivariate logistic regression were used. P < 0.05 was considered significant.

Results: Among 50,237 deliveries from July 1, 2005 to June 30, 2011, there were 562 cesarean sections in diagnosed cases of placenta previa. Cesarean deliveries (479) were performed under spinal anesthesia (81%), epidural anesthesia (1.8%), and if the effects spinal anesthesia dissipated, general anesthesia (2.3%). Among 46 cases of cesarean hysterectomy, 27 patients (58.7%) received regional anesthesia. However, 6 of 10 patients with planned cesarean hysterectomy underwent general anesthesia, while 1 of 4 of a group with regional anesthesia needed conversion to general anesthesia. There was no serious anesthesia-related complication. Factors related to general anesthesia were: a higher American Society of Anesthesiologists (ASA) physical status OR 2.7 (95% CI 1.7-4.3) P < 0.001; presentation with bleeding OR 1.8(95% CI 1.0-3.1) P = 0.033; anterior site of placenta OR 1.8 (95% CI 1.1-3.2) P = 0.025; heart rate >125 bpm OR 5.6 (95% CI 1.5-214) P = 0.01; and pack red cell transfusion OR 3.4 (95% CI 2.0-5.7) P < 0.001.

Conclusions: Most parturients received regional anesthesia. Neuroaxial anesthesia and general anesthesia are safe.

Safety of cesarean delivery through placental incision in patients with anterior placenta previa

OBJECTIVE

To demonstrate the safety of fetal delivery through placental incision in a placenta previa pregnancy.

METHODS

We examined the medical records of 80 women with singleton pregnancy diagnosed with placenta previa who underwent cesarean section between May 2010 and May 2015 at the Department of Obstetrics and Gynecology, Chungbuk National University Hospital. Among the women with placenta previa, those who did not have the placenta in the uterine incision site gave birth via conventional uterine incision, while those with anterior placenta previa or had placenta attached to the uterine incision site gave birth via uterine incision plus placental incision. We compared the postoperative hemoglobin level and duration of hospital stay for the mother and newborn of the two groups.

RESULTS

There was no difference between the placental incision group and non-incision group in terms of preoperative and postoperative hemoglobin change, the amount of blood transfusions required by the mother, newborns with 1-min or 5-min Apgar scores below 7 points or showing signs of acidosis on umbilical cord blood gas analysis result of pH below 7.20. Moreover, neonatal hemoglobin levels did not differ between the two groups.

CONCLUSION

Fetal delivery through placental incision during cesarean section for placenta previa pregnancy does not negatively influence the prognosis of the mother or the newborn, and therefore, is considered a safe surgical technique.

Placenta previa associated with severe bleeding leading to hospitalization and delivery: a retrospective population-based cohort study

INTRODUCTION

The aim of our study was to compare maternal and neonatal outcomes in women with placenta previa complicated with severe bleeding leading to hospitalization until delivery versus those without severe bleeding episodes.

METHODS

This is a population-based retrospective cohort study including all pregnant women with placenta previa who delivered at our medical center in the study period, divided into the following groups: 1) women with severe bleeding leading to hospitalization resulting with delivery (n = 32); 2) patients with placenta previa without severe bleeding episodes (n = 1217).

RESULTS

Out of all women with placenta previa who delivered at our medical center, 2.6% (32/1249) had an episode of severe bleeding leading to hospitalization and resulting with delivery. The rate of anemia was lower (43.8% versus 63.7%, p = 0.02) while the need for blood transfusion higher (37.5% versus 21.1%, p = 0.03) in the study group. The rate of cesarean sections was significantly different between the groups, and a logistic regression model was constructed in order to find independent risk factors for cesarean section in our patients.

CONCLUSION

To the best of our knowledge, this is the first study to evaluate the impact of severe bleeding on the outcome of pregnancies complicated with placenta previa. Our study demonstrates that, in women with placenta previa, severe bleeding does not lead to increased adverse maternal or neonatal outcomes.

Abnormal Placentation: Placenta Previa, Vasa Previa, and Placenta Accreta

Placental disorders such as placenta previa, placenta accreta, and vasa previa are all associated with vaginal bleeding in the second half of pregnancy. They are also important causes of serious fetal and maternal morbidity and even mortality. Moreover, the rates of previa and accreta are increasing, probably as a result of increasing rates of cesarean delivery, maternal age, and assisted reproductive technology. The routine use of obstetric ultrasonography as well as improving ultrasonographic technology allows for the antenatal diagnosis of these conditions. In turn, antenatal diagnosis facilitates optimal obstetric management. This review emphasizes an evidence-based approach to the clinical management of pregnancies with these conditions as well as highlights important knowledge gaps.

Major Placenta Previa: Rate, Maternal and Neonatal Outcomes Experience at a Tertiary Maternity Hospital, Sohag, Egypt: A Prospective Study

INTRODUCTION

Major degree placenta is a serious health issue and is associated with high fetal-maternal morbidity and mortality. Literature from developing countries is scant.

AIM

To determine the prevalence and maternal and neonatal outcomes among women with major placenta previa (PP).

MATERIALS AND METHODS

A prospective descriptive study of 52 singleton pregnancies with PP was evaluated in this study. The study was conducted at Sohag University Hospital, Egypt from January through June 2014. Outcome measures, including the prevalence of PP, maternal and neonatal outcomes, and case-fatality rate.

RESULTS

The total number of deliveries performed during the study period was 3841, of them, 52 cases were placenta previa. Thus, the prevalence of PP was 1.3%. The mean of previous cesarean scars was 2.2±1.4. Of women with PP, 26.4% (n=14) had placenta accreta. In total, 15.1% (n=8) of women underwent an obstetric hysterectomy. From the total no. of babies, 13.2% (n=7) were delivered fresh stillborn babies. Of the surviving babies (n=45), 20% (n=9) required admission to NICU. The frequencies of bowel and bladder injuries were 3.8% (n=2) and 13.2% (n=7) respectively. There was no maternal death in this study.

CONCLUSION

The rate of PP is comparable to previous studies, however, the rate of placenta accreta is high. Also, there are high rates of neonatal mortality and intraoperative complications which can be explained by accreta. The study highlights the need to revise maternity and child health services.

Efficacy of Intrauterine Bakri Balloon Tamponade in Cesarean Section for Placenta Previa Patients

PURPOSE

The aims of this study were to analyze the predictive factors for the use of intrauterine balloon insertion and to evaluate the efficacy and factors affecting failure of uterine tamponade with a Bakri balloon during cesarean section for abnormal placentation.

METHODS

We reviewed the medical records of 137 patients who underwent elective cesarean section for placenta previa between July 2009 and March 2014. Cesarean section and Bakri balloon insertion were performed by a single qualified surgeon. The Bakri balloon was applied when blood loss during cesarean delivery exceeded 1,000 mL.

RESULTS

Sixty-four patients (46.7%) required uterine balloon tamponade during cesarean section due to postpartum bleeding from the lower uterine segment, of whom 50 (78.1%) had placenta previa totalis. The overall success rate was 75% (48/64) for placenta previa patients. Previous cesarean section history, anterior placenta, peripartum platelet count, and disseminated intravascular coagulopathy all significantly differed according to balloon success or failure (all p<0.05). The drainage amount over 1 hour was 500 mL (20-1200 mL) in the balloon failure group and 60 mL (5-500 mL) in the balloon success group (p<0.01).

CONCLUSION

Intrauterine tamponade with a Bakri balloon is an adequate adjunct management for postpartum hemorrhage following cesarean section for placenta previa to preserve the uterus. This method is simple to apply, non-invasive, and inexpensive. However, possible factors related to failure of Bakri balloon tamponade for placenta previa patients such as prior cesarean section history, anterior placentation, thrombocytopenia, presence of DIC at the time of catheter insertion, and catheter drainage volume more than 500 mL within 1 hour of catheter placement should be recognized, and the next-line management should be prepared in advance.

Fetal imaging: executive summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging (MRI) in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and MRI in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost effectiveness, and to identify research opportunities. This article is the executive summary of the workshop.

Fetal imaging: Executive summary of a Joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging Workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and magnetic resonance imaging in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost-effectiveness and to identify research opportunities. This article is the executive summary of the workshop.

Fetal imaging: executive summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging Workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging (MRI) in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and MRI in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost effectiveness, and to identify research opportunities. This article is the executive summary of the workshop.

Toward consistent terminology of placental location

The diagnosis of placenta previa has shifted from clinical examination of the dilated cervix to sonographic assessment of the closed internal os, resulting in terminology confusion. If the cervix is closed, the distinction between a placental edge at the cervical margin and one partially covering the os is neither reliable nor clinically important. Cesarean delivery is recommended if the placenta reaches the cervical margin at time of delivery, and this entity may be grouped with placenta previa. Partial previa should probably be restricted to those with cervical dilatation. The terms marginal previa and low-lying placenta have been used interchangeably. However, if the placenta implants in the lower uterine segment but does not reach the cervix, low-lying placenta is preferred, and vaginal delivery may be achieved, depending on placental-os distance and presence of bleeding. Limited data suggest that if the placenta is within 2 cm of the os-low-lying placenta, cesarean delivery is performed for bleeding in one-third of cases.

The influence of pregnancy termination on the outcome of subsequent pregnancies: a retrospective cohort study

OBJECTIVE

To compare the incidences of preterm delivery, cervical incompetence treated by cerclage, placental implantation or retention problems (ie, placenta praevia, placental abruption and retained placenta) and postpartum haemorrhage between women with and without a history of pregnancy termination.

DESIGN

 A retrospective cohort study using aggregated data from a national perinatal registry.

SETTING

All midwifery practices and hospitals in the Netherlands.

PARTICIPANTS

All pregnant women with a singleton pregnancy without congenital malformations and a gestational age of ≥20 weeks who delivered between January 2000 and December 2007.

MAIN OUTCOME MEASURES

Preterm delivery, cervical incompetence treated by cerclage, placenta praevia, placental abruption, retained placenta and postpartum haemorrhage.

RESULTS

A previous pregnancy termination was reported in 16 000 (1.2%) deliveries. The vast majority of these (90-95%) were performed by surgical methods. The incidence of all outcome measures was significantly higher in women with a history of pregnancy termination. Adjusted ORs (95% CI) for cervical incompetence treated by cerclage, preterm delivery, placental implantation or retention problems and postpartum haemorrhage were 4.6 (2.9 to 7.2), 1.11 (1.02 to 1.20), 1.42 (1.29 to 1.55) and 1.16 (1.08 to 1.25), respectively. Associated numbers needed to harm were 1000, 167, 111 and 111, respectively. For any listed adverse outcome, the number needed to harm was 63.

CONCLUSIONS

In this large nationwide cohort study, we found a positive association between surgical termination of pregnancy and subsequent preterm delivery, cervical incompetence treated by cerclage, placental implantation or retention problems and postpartum haemorrhage in a subsequent pregnancy. Absolute risks for these outcomes, however, remain small. Medicinal termination might be considered first whenever there is a choice between both methods.

Increased risk of placenta previa is associated with endometriosis and tubal factor infertility in assisted reproductive technology pregnancy

Although assisted reproductive technology (ART) is suspected to increase the risk of placenta previa, a life-threatening complication of pregnancy, the reason is poorly understood. We recruited consecutive 318 pregnancies conceived by ART in our clinic and examined relation of ten variables, i.e. maternal age, gravidity, parity, male or female fetus, previous abortion, previous cesarean delivery, endometriosis, ovulatory disorder, tubal disease, and male infertility, to placenta previa, by logistic regression analysis. As a result, we found that endometriosis (odds ratio = 15.1; 95% CI = 7.6-500.0) and tubal disease (odds ratio = 4.4; 95% CI = 1.1-26.3) were significantly associated with placenta previa. It would be preferable to take the increased risk of placenta previa into account in treating ART pregnancy with endometriosis and tubal disease.

Complications in late pregnancy

Complications of late pregnancy are managed infrequently in the emergency department and, thus, can pose a challenge when the emergency physician encounters acute presentations. An expert understanding of the anatomic and physiologic changes and possible complications of late pregnancy is vital to ensure proper evaluation and care for both mother and fetus. This article focuses on the late pregnancy issues that the emergency physician will face, from the bleeding and instability of abruptio placentae to the wide spectrum of complications and management strategies encountered with preterm labor.

Implications of the first cesarean: perinatal and future reproductive health and subsequent cesareans, placentation issues, uterine rupture risk, morbidity, and mortality

Rates of cesarean delivery have substantially increased worldwide during the past 30 years. Indeed, almost one-third of deliveries in the United States are cesareans. Most cesareans are safe, and major complications are uncommon. However, there is a "concealed" downside to cesarean deliveries. There are rare but life-threatening morbidities that may occur, which are often overlooked because most cesareans go well. In addition, subsequent pregnancies are fraught with an increased risk of both maternal and fetal complications. The worst of these are associated with placental problems such as previa, abruption, and accreta. The risk dramatically worsens in patients with multiple repeat cesarean deliveries. This article will summarize and highlight the implications of the rising cesarean rate on maternal and fetal morbidity and mortality.

Early preterm delivery due to placenta previa is an independent risk factor for a subsequent spontaneous preterm birth

BACKGROUND

To determine whether patients with placenta previa who delivered preterm have an increased risk for recurrent spontaneous preterm birth.

METHODS

This retrospective population based cohort study included patients who delivered after a primary cesarean section (n = 9983). The rate of placenta previa, its recurrence, and the risk for recurrent preterm birth were determined.

RESULTS

Patients who had a placenta previa at the primary CS pregnancy had an increased risk for its recurrence [crude OR of 2.65 (95% CI 1.3-5.5)]. The rate of preterm birth in patients with placenta previa in the primary CS pregnancy was 55.9%; and these patients had a higher rate of recurrent preterm delivery than the rest of the study population (p < .001). Among patients with placenta previa in the primary CS pregnancy, those who delivered preterm had a higher rate of recurrent spontaneous preterm birth regardless of the location of their placenta in the subsequent delivery [OR 3.09 (95% CI 2.1-4.6)]. In comparison to all patients with who had a primary cesarean section, patients who had placenta previa and delivered preterm had an independent increased risk for recurrent preterm birth [OR of 3.6 (95% CI 1.5-8.5)].

CONCLUSIONS

Women with placenta previa, who deliver preterm, especially before 34 weeks of gestation, are at increased risk for recurrent spontaneous preterm birth regardless to the site of placental implantation in the subsequent pregnancy. Thus, strict follow up by high risk pregnancies specialist is recommended.