Placenta previa without morbidly adherent placenta: comparison of characteristics and outcomes between planned and emergent deliveries in a tertiary center

Objective: The objective of this study is to compare patient outcomes between planned and emergent cesarean deliveries for placenta previa without morbidly adherent placenta.

Study design: All patients with confirmed, persistent placenta previa (without morbidly adherent placentation) who underwent the surgery between January 2010 and April 2016 were included in this retrospective study. Primary outcome was composite maternal morbidity defined as the presence of at least one of the followings: death, red blood cell (RBC) transfusion, hysterectomy, reoperation, hospital stay >7 d, ureteral injury, bowel injury, or cystotomy.

Results: Three hundred and four patients with placenta previa were identified during the study period, of whom 154 (50.65%) had an antenatal and 10 (3.28%) had an intraoperative diagnosis of morbidly adherent placenta. One hundred and forty patients met the inclusion criteria. Eighty (57.1%) underwent planned cesarean delivery (planned cesarean delivery (PCD) group), and 60 (42.8%) required emergent cesarean delivery due to uterine contractions and/or bleeding (emergent cesarean delivery (ECD) group). Baseline characteristics were similar between the two groups except for the gestational age at delivery (36.0 weeks (36.0, 37.0) in PCD versus 34.0 weeks (32.0, 36.0) in ECP, p?p?=?.35)

Conclusions: In our referral tertiary centre, emergent and planned cesarean deliveries for placenta previa without morbidly adherent placenta have similar maternal outcomes. In patients without significant hemorrhage, delivery may be safely deferred until 36–37 weeks.     

Abnormal placentation: twenty-year analysis

OBJECTIVE: This study was undertaken to determine whether the rate of abnormal placentation is increasing in conjunction with the cesarean rate and to evaluate incidence, risk factors, and outcomes. STUDY DESIGN: Cases from 1982-2002 were identified by histopathologic or strong clinical criteria. Risk factors were assessed in a matched case-control study, and analyzed using conditional logistic regression models. RESULTS: There were 64,359 deliveries, with cesarean rates increasing from 12.5% (1982) to 23.5% (2002). The overall incidence of placenta accreta was 1 in 533. Significant risk factors for placenta accreta in our final analysis included advancing maternal age (odds ratio [OR] 1.13, 95% CI 1.089-1.194, P < .0001), 2 or more cesarean deliveries (OR 8.6, 95% CI 3.536-21.078, P < .0001), and previa (OR 51.4, 95% CI: 10.646-248.390, P < .0001). CONCLUSION: The rate of placenta accreta increased in conjunction with cesarean deliveries; the most important risk factors were previous cesarean delivery, previa, and advanced maternal age.     

Peripartum hysterectomy in 38 hospitals in China: a population-based study

Objective

To investigate the incidence, indications, risk factors and transfusions of peripartum hysterectomy in China.

Methods

A population-based study was conducted using inpatient records of 38 hospitals between 1 January 2011 and 31 December 2011; multivariate logistic regression analysis was used to identify independent risk factors for peripartum hysterectomy.

Results

During the study period, there were 43 peripartum hysterectomy cases out of 114,420 deliveries (0.38 ‰). Abnormal placentation was major indication for peripartum hysterectomy. Several factors significantly increased the risk of peripartum hysterectomy in this population: placenta previa/accreta [adjusted odds ratio (aOR) 49.7, 95 % CI 25.0–98.9], maternal age ≥35 years (aOR 8.1, 95 % CI 4.0–16.0), preeclampsia/eclampsia (aOR 7.5, 95 % CI 2.6–21.7), cesarean delivery (aOR 3, 95 % CI 1.1–8.0), and multiparity (aOR 2.7, 95 % CI 1.2–5.4). In contrast, multiple gestations did not.

Conclusions

Placenta previa/accreta, maternal age ≥35 years, preeclampsia/eclampsia, cesarean delivery and multiparity were risk factors of peripartum hysterectomy.     

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.     

The effect of cesarean delivery rates on the future incidence of placenta previa,placenta accreta,and maternal mortality

Objective.?The overall annual incidence rate of caesarean delivery in the United Sates has been steadily rising since 1996, reaching 32.9% in 2009. Primary cesareans often lead to repeat cesareans, which may lead to placenta previa and placenta accreta. This study's goal was to forecast the effect of rising primary and secondary cesarean rates on annual incidence of placenta previa, placenta accreta, and maternal mortality.

Methods.?A decision-analytic model was built using TreeAge Pro software to estimate the future annual incidence of placenta previa, placenta accreta, and maternal mortality using data on national birthing order trends and cesarean and vaginal birth after cesarean rates. Baseline assumptions were derived from the literature, including the likelihood of previa and accreta among women with multiple previous cesarean deliveries.

Results. If primary and secondary cesarean rates continue to rise as they have in recent years, by 2020 the cesarean delivery rate will be 56.2%, and there will be an additional 6236 placenta previas, 4504 placenta accretas, and 130 maternal deaths annually. The rise in these complications will lag behind the rise in cesareans by approximately 6 years.

Conclusions.?If cesarean rates continue to increase, the annual incidence of placenta previa, placenta accreta, and maternal death will also rise substantially.     

Composite neonatal and maternal morbidities with small- versus appropriate- for gestational age among uncomplicated obese women undergoing repeat cesarean delivery*

Purpose: Our goal was to compare composite neonatal and maternal morbidities (composite neonatal morbidity (CNM), composite maternal morbidity (CMM)) among deliveries with small for age (SGA) versus appropriate for gestational age (AGA; birthweight 10–89%) among obese versus non-obese women undergoing repeat cesarean delivery (CD).

Study design: This is a secondary analysis of a prospective observational study. Women who had elective CD ≥37 weeks were studied. We excluded multiple gestations, fetal anomalies,?>?1 prior CD, and medical diseases. Patients were divided into BMI ≥30 versus <30?kg/m². CNM included respiratory distress syndrome, necrotizing enterocolitis, severe intraventricular hemorrhage, seizure, or death; CMM included transfusion, hysterectomy, operative injury, coagulopathy, thromboembolism, pulmonary edema, or death. Multivariate logistic regression was used to control for confounding factors.

Results: Of 7561 women, we included 65% were obese and 35% were not. SGA rates differed significantly: 8 versus 12% (p?Conclusions: SGA occurred in 8% of low-risk obese women with prior CD. CNM of SGA babies in obese versus non-obese women were similar. Paradoxically, CMM was lower in obese cases, possibly reflecting the caution that obese patients receive preoperatively. Our findings may assist in counseling patients and designing trials.     

Peripartum cesarean hysterectomy: critical analysis of risk factors and trends over the years

Objective.?To investigate time trends and risk factors for peripartum cesarean hysterectomy.

Methods.?A population-based study comparing all deliveries that were complicated with peripartum hysterectomy to deliveries without this complication was conducted. Deliveries occurred during the years 1988–2007 at a tertiary medical center. A multiple logistic regression model was constructed to find independent risk factors associated with peripartum hysterectomy.

Results.?Emergency peripartum cesarean hysterectomy complicated 0.06% (n?=?125) of all deliveries in the study period (n?=?211,815). The incidence of peripartum hysterectomy increased over time (1988–1994, 0.04%; 1995–2000, 0.05%; 2001–2007, 0.095%). Independent risk factors for emergency peripratum hysterectomy from a backward, stepwise, multivariable logistic regression model were: uterine rupture (OR?=?487; 95% CI 257.8–919.8, p?<?0.001), placenta previa (OR?=?66.4; 95% CI 39.8–111, p?<?0.001), postpartum hemorrhage (PPH) (OR?=?40.8; 95% CI 22.4–74.6, p?<?0.001), cervical tears (OR?=?22.3; 95% CI 10.4–48.1, p?<?0.001), second trimester bleeding (OR?=?6; 95% CI 1.8–20, p?=?0.003), previous cesarean delivery (OR?=?5.4; 95% CI 3.5–8.4, p?<?0.001), placenta accreta (OR?=?4.7; 95% CI 1.9–11.7, p?=?0.001), and grand multiparity (above five deliveries, OR?=?4.1; 95% CI 2.5–6.6, p?<?0.001). Newborns of these women had lower Apgar scores (<7) at 1 and 5?min (32.7% vs.4.4%; p?<?0.001, and 10.5% vs. 0.6%; p?<?0.001, respectively), and higher rates of perinatal mortality (18.4% vs. 1.4%; p?<?0.001) as compared to the comparison group.

Conclusion.?Significant risk factors for peripartum hysterectomy are uterine rupture, placenta previa, PPH, cervical tears, previous cesarean delivery, placenta accreta, and grand multiparity. Since the incidence rates are increasing over time, careful surveillance is warranted. Cesarean deliveries in patients with placenta previa-accreta, specifically those performed in women with a previous cesarean delivery, should involve specially trained obstetricians, following informed consent regarding the possibility of peripartum hysterectomy.     

Prostaglandin versus mechanical dilation and the effect of maternal obesity on failure to achieve active labor: a cohort study

Purpose: Assess the impact of obesity on successful cervical ripening with mechanical versus prostaglandin ripening.

Materials and methods: We compared obese to non-obese women in an analysis stratified by induction method, prostaglandin versus mechanical. Misoprostol dosing was the same for obese and non-obese women. Pitocin was titrated to effect. Our primary outcome was failure to achieve active labor. Secondary outcomes included overall cesarean delivery rate, doses of misoprostol used and need for protocol deviation.

Results: Obese women had a higher cesarean delivery rate with misoprostol (35% versus 26%, p?=?0.03) but not with mechanical ripening (31% versus 29%, p?=?0.69). Obesity was associated with a higher rate of failure to achieve active labor in women undergoing prostaglandin ripening with misoprostol (24 versus 15%, p?=?0.01) but not in women undergoing mechanical ripening (19 versus 15%, p?=?0.55). After controlling for confounding variables, obese women who underwent cervical ripening with misoprostol had a higher rate of failure to achieve active labor, aOR 1.29 (95%CI: 1.00–1.67), which was not seen with mechanical ripening, aOR 1.09 (95%CI: 0.69–1.73).

Conclusion: Obese women receiving the same dose of misoprostol as non-obese women have higher rates of failure to achieve active labor, an effect not seen with mechanical ripening.     

Obstetrical and neonatal outcomes of pregnancies complicated by endometriosis

Objective: Endometriosis is defined as the presence of endometrial-like tissue outside the uterus, associated with pelvic pain and subfertility, affecting 0.6–10% of the general female population. The association between endometriosis and obstetrical outcomes is not well established. We aimed to evaluate whether endometriosis is associated with a higher incidence of obstetrical and neonatal complications.

Study design: A retrospective cohort study of all deliveries in a university-affiliated tertiary hospital (2007–2014). Eligibility was limited to women with previously diagnosed endometriosis and singleton pregnancies. Fetuses or neonates diagnosed with structural or chromosomal anomalies were excluded. We compared labor and delivery outcomes and immediate neonatal outcomes among women with endometriosis compared with women without endometriosis.

Results: Overall, 61,535 deliveries were eligible for analysis, of which 135 (0.002%) had endometriosis. Women with in the endometriosis group were characterized by higher maternal age, lower parity and higher nulliparity rate, and an earlier gestational age at delivery. Women with endometriosis had higher rate of failure of induction of labor (aOR 5.2, 95%CI 1.8–14.9), cesarean delivery (aOR 5.0, 95%CI 3.3–7.4), postpartum hemorrhage (aOR 3.7, 95%CI 1.6–8.5), placenta accreta (aOR 6.24, 95%CI 2.20–17.67), postpartum hemoglobin <10?mg/dL (aOR 2.03, 95%CI 1.31–3.14), and packed cell transfusion (aOR 3.66, 95%CI 1.94–6.91). No significant differences in neonatal outcomes were observed.

Conclusions: Endometriosis is associated with higher risk of cesarean delivery and postpartum hemorrhage. Our findings suggest appropriate preparations for delivery, such as uterotonic agents and blood products, should be considered in these women.     

Association between maternal serum alpha-fetoprotein and adverse outcomes in pregnancies with placenta previa

OBJECTIVE: To determine whether increased maternal serum alpha-fetoprotein (MSAFP) level at 15-20 weeks' gestation is a marker of adverse outcomes in women with placenta previa at delivery. METHODS: We conducted a retrospective cohort study of singleton pregnancies complicated by placenta previa, diagnosed sonographically, and confirmed at delivery. All women had MSAFP screening at 15-20 weeks' gestation and delivered nonanomalous live-born infants at or after 24 weeks' gestation. RESULTS: One hundred seven women with placenta previa delivered during the study. Fourteen (13%, 95% CI 7%, 21%) had MSAFP at least 2.0 multiples of the median (MoM). They were significantly more likely than those with lower MSAFP levels to have one or more of the following outcomes: hospitalization for antepartum bleeding before 30 weeks' gestation (50% versus 15%), delivery before 30 weeks' gestation (29% versus 5%), or preterm delivery for pregnancy-associated hypertension before 34 weeks' gestation (14% versus none). The MSAFP cutoff of 2.0 MoM provided the best combination of sensitivity and specificity for those outcomes, using receiver operating characteristic curves. CONCLUSION: Women with placenta previa who also have high MSAFP levels are at increased risk of bleeding in the early third trimester and preterm birth. We did not find women who required cesarean hysterectomy, including those with placenta accreta, to consistently have elevated MSAFP.     

Risk factors for postpartum hemorrhage requiring transfusion in cesarean deliveries for Japanese twins: comparison with those for singletons

Objective

The aim of this study was to identify the factors associated with the increased risk of postpartum hemorrhage requiring transfusion in Japanese twin pregnancies in comparison with those in Japanese singleton pregnancies.

Methods

We reviewed the obstetric records of all singleton and twin deliveries after 22?weeks’ gestation at the Japanese Red Cross Katsushika Maternity Hospital from 2003 through 2011. Potential risk factors for transfusion due to hemorrhage after cesarean delivery were selected according to previous studies of postpartum hemorrhage or transfusion or both after delivery: maternal age, parity, previous cesarean deliveries, history of infertility therapies such as in vitro fertilization, gestational age at delivery, neonatal birth weight, placenta previa, uterine myoma ≥6?cm, hypertensive disorders, placental abruption, emergency cesarean deliveries and general anesthesia.

Results

Using multiple logistic regression, the independent risk factors for postpartum hemorrhage requiring transfusion in singleton pregnancies were preterm delivery [odds ratio (OR) 2.40, 95?% confidence interval (CI) 1.2–4.6, p?<?0.01], placenta previa (OR 8.08, 95?% CI 3.9–16, p?<?0.01) and placental abruption (OR 12.8, 95?% CI 2.3–76, p?<?0.01). In twin pregnancies, however, the independent risk factors for postpartum hemorrhage requiring transfusion were gestational age at ≥41?weeks (OR 8.20, 95?% CI 1.3–40, p?<?0.01) and hypertensive disorders (OR 5.45, 95?% CI 2.2–14, p?<?0.01).

Conclusions

The factors associated with postpartum hemorrhage requiring transfusion in cesarean deliveries of twins seemed to be different from those in singleton cesarean deliveries.     

Placenta accreta--summary of 10 years: a survey of 310 cases

The objective was to study the incidence, risk factors, and outcome of pregnancies complicated by placenta accreta in our population. Retrospective analysis of all deliveries between the years 1990-2000, and identification of all cases of placenta accreta, defined by clinical or histological criteria. For comparison purposes we defined two sub-groups: (i) all cases that ended with severe outcome and (ii) all patients who had a previous event of placenta accreta in one or more of their previous deliveries. We evaluated the potential risk factors leading to these conditions. The SPSS software package was used for statistical analysis. Univariate and multivariate analyses were performed by stepwise logistic regression. The study covered 34 450 deliveries from which 310 cases of placenta accreta were diagnosed (0.9 per cent). The risk factors associated with placenta accreta were previous cesarean delivery (12 per cent), advanced maternal age, high gravidity, multiparity, previous curettage and placenta previa (10 per cent). Hysterectomy was performed in 11 patients (3.5 per cent) with one case of maternal death, whereas 21 per cent of the patients required postpartum blood products transfusion. Antenatal diagnosis of placenta accreta or percreta by ultrasound or MRI, was achieved only in eight of the cases. In the sub-group of 15 patients (4.8 per cent) with severe outcome, the only significant risk factors were increased parity (O.R.=1.29, 95 per cent CI 1.056-1.585), anteriorly low placenta (O.R.=6.1, 95 per cent CI 1.4-25.3) and repeated cases of caesarean sections (O.R.=3.3, 95 per cent CI 0.9-12.5), whereas in the 49 (16 per cent) patients with repeated cases of placenta accreta the only significant risk factor was the number of deliveries (O.R.=1.5, 95 per cent CI 1.0-2.2). Repeated cesarean delivery, high parity, and anteriorly low placental location are associated with severe outcome in case of placenta accreta. Women with repeated events of placenta accreta may have better outcome and a genetic factor may serve as a cause for this condition.     

A theoretical analysis of prophylactic common iliac arterial occlusion for potential massive bleeding during cesarean delivery: Decision-making considerations — A 2-year retrospective study

ObjectiveAccording to the American College of Obstetricians and Gynecologists, there has been a rapid increase in the total cesarean birth rates. The rate of placenta accreta is increasing, and previous cesarean delivery is the most common risk factor. Labor is a major challenge in cases with an abnormally invasive placenta, considering the risk of massive blood loss during cesarean delivery and patient wishes for uterine preservation.Materials and methodsWe retrospectively obtained clinical data and surgical outcomes of high-risk cases of placenta previa totalis and placenta accreta admitted between March 2018 and September 2020. A multidisciplinary discussion was conducted before surgery. We also constructed an organizational flowchart detailing this decision-making process.ResultsPatients who underwent cesarean delivery for suspected placenta accreta or placenta previa totalis with clinical risk factors were reviewed. No patient required an emergency hysterectomy or intensive care unit admission.ConclusionWe shared our experience of multidisciplinary decision-making by presenting high-risk cases of placenta previa totalis with clinical risk factors or suspected placenta accreta. Based on our multidisciplinary decision-making process, all patients were discharged without complications.     

Pre-delivery remifentanil infusion for placenta accreta cesarean delivery under general anesthesia: an observational study

Objective: General anesthesia may be required for placenta accreta cesarean delivery. Intrauterine fetal anesthetic exposure should be minimized to avoid neonatal respiratory depression; opioids are often delayed until post-delivery.

Methods: In this observational study, we compared neonatal outcome using pre-delivery remifentanil versus post-delivery (deferred) opioids for placenta accreta cesarean delivery. Choice of anesthesia was discretionary. The primary outcome was Apgar score at 5?min comparing women who received pre-delivery remifentanil versus deferred opioid administration. We recorded maternal/obstetric characteristics, surgical characteristics, maternal hemodynamic data, neonatal outcomes: Apgar scores, umbilical vein pH and respiratory interventions at birth.

Results: Between February 2007 and April 2014 we identified 40 general anesthesia placenta accreta cesarean deliveries. The remifentanil dose rate ranged from 0.06 to 0.46 mcg?kg^?1?min^?1. Obstetric and maternal characteristics were similar. Neonatal Apgar, umbilical pH and respiratory intervention outcomes were similar in both groups; Apgar scores median (interquartile range IQR [range]) at 5?min were 9 (8–10) for pre-delivery remifentanil versus 9 (9–10) for deferred opioid administration, p?=?0.18.

Conclusions: We did not observe a significant effect on neonatal Apgar scores at 1 and 5?min, or respiratory interventions at birth when remifentanil infusion was administered pre-delivery.     

Maternal hemoglobin decline following ‘uneventful’ cesarean delivery

Objective: To assess hemoglobin (Hb) decline following elective and non-elective uneventful cesarean section (CS).

Methods: A retrospective cohort study of all women with singleton pregnancy who underwent uneventful CS defined as clinical estimation of intra-operative bleeding?<?1000?ml. Hemoglobin decline (pre- and post-CS levels difference) of women with non-elective CS (during labor/delivery process) were compared to those who underwent elective CS (no labor). Cases complicated by placenta previa/abruption were excluded.

Results: Overall 2767 women underwent uneventful CS, of them, 954 (34.5%) were non-elective and 1813 (65.5%) were elective. Hemoglobin decline was higher in the non-elective group (1.5?±?1.3 versus 1.0?±?1.2?g/dL, p?<?0.001). This was also observed in the nulliparous patients as well as in those with previous single CS subgroups. The rate of Hb decline?≥3?g/dL and the rate of post-CS Hb?<?7?g/dL were higher in the non-elective group (8.9% versus 3.1%, p?<?0.001 and 2.3% versus 0.4%, p?=?0.001, respectively). On multivariable analysis, non-elective CS was found to be significantly associated with Hb decline of ≥3?g/dl after surgery (aOR?=?2.10, 95% CI 1.36–3.23, p?=?0.001) and need for blood products transfusion (aOR?=?2.24, 95% CI 1.04–4.83, p?=?0.03).

Conclusion: Non-elective CS was associated with an increased risk of Hb decline and blood product transfusion even in an apparent uneventful operation.     

Placenta previa and maternal hemorrhagic morbidity

Objective: Placenta previa is associated with maternal hemorrhage, but most literature focuses on morbidity in the setting of placenta accreta. We aim to characterize maternal morbidity associated with previa and to define risk factors for hemorrhage.

Methods: This is a secondary cohort analysis of the NICHD Maternal–Fetal Medicine Units Network Cesarean Section Registry. This analysis included all women undergoing primary Cesarean delivery without placenta accreta. About 496 women with previa were compared with 24,201 women without previa. Primary outcome was composite maternal hemorrhagic morbidity. Non-hemorrhagic morbidities and risk factors for hemorrhage were also evaluated.

Results: Maternal hemorrhagic morbidity was more common in women with previa (19 versus 7%, aRR 2.6, 95% CI 1.9–3.5). Atony requiring uterotonics (aRR 3.1, 95% CI 2.0–4.9), red blood cell transfusion (aRR 3.8, 95% CI 2.5–5.7), and hysterectomy (aRR 5.1, 95% CI 1.5–17.3) were also more common with previa. For women with previa, factors associated with maternal hemorrhage were pre-delivery anemia, thrombocytopenia, diabetes, magnesium use, and general anesthesia.

Conclusion: Placenta previa is an independent risk factor for maternal hemorrhagic morbidity. Some risk factors are modifiable, but many are intrinsic to the clinical scenario.     

Pregnancy outcome in women aged 40 years or more

Objective: The study aimed to analyze the pregnancy outcome of women aged 40 years or more. Methods: A matched retrospective cohort study comparing women aged 40 years or more with a control group aged 20 to 30 years is described. Multivariate logistic regression models were fitted for the prediction of preterm birth and cesarean delivery. Results: Pregnancy-induced hypertension, preeclampsia and placenta previa were similar in both groups, but a higher rate of gestational diabetes was found in elderly patients (odds ratio [OR] 3.820, 95% confidence interval [CI] = 1.400–10.400; p < 0.0001). Preterm delivery was significantly more frequent in elderly women (OR 1.847, 95% CI = 1.123–3.037; p = 0.020). Gestational diabetes and pregnancy-induced hypertension were strongly associated with preterm delivery and advanced maternal age was not an independent risk factor for preterm delivery. The cesarean delivery rate was significantly higher in the study group (OR 3.234, 95% CI = 2.266–4.617; p < 0.0001). The variables most influencing the cesarean delivery rate were maternal age, analgesia, parity, premature rupture of the membranes and gestational hypertension. No significant differences were detected in neonatal birth weight and Apgar score. Conclusions: Patients aged 40 years or more have been demonstrated to carry a favorable pregnancy and neonatal outcome, similar to younger patients. The risk of cesarean delivery was higher in patients with advanced maternal age, in nulliparous and in women with a previous cesarean section. The risk of preterm delivery was not related to age but it was strongly associated with gestational diabetes and pregnancy-induced hypertension.     

Maternal and neonatal outcomes among scheduled versus unscheduled deliveries in women with prenatally diagnosed,pathologically proven placenta accreta

Objective: To evaluate maternal and neonatal outcomes among scheduled versus unscheduled deliveries in cases of prenatally diagnosed, pathologically proven placenta accreta.

Study design: Retrospective cohort of placenta accreta cases delivered in five University of California hospitals.

Results: Of 151 cases of histopathologically proven placenta accreta, 82% were prenatally diagnosed. Sixty-seven percent of women underwent scheduled deliveries and 33% were unscheduled. There were no differences in demographics between groups except a higher rate of antepartum bleeding in the unscheduled delivery group (81 versus 53%; p?=?.003). Scheduled deliveries were associated with a later gestational age at delivery (34.6 versus 32.6 weeks; p?=?.001), lower blood loss (2.0 versus 2.5?l; p?=?.04), higher birth weight (2488 versus 2010?g; p?p?=?.03) and neonatal length of stay (12 versus 20 d; p?=?.005).

Conclusion: Despite a prenatal diagnosis of placenta accreta, 1/3 of these cases require unscheduled delivery, portending poorer maternal and neonatal outcomes.     

Placenta previa and antepartum hemorrhage after previous cesarean section

A prospective study was conducted to determine the risk of placenta previa and unexplained antepartum hemorrhage after a previous cesarean section (CS). Of a total of 24,644 patients, 81 (0.33%) had a placenta previa which demanded abdominal delivery. The risk of placenta previa was 0.25% with an unscarred uterus and 1.22% in patients with one or more previous CS (the difference was statistically significant p less than 0.001). The corresponding figures for unexplained antepartum hemorrhage were 0.40% and 3.81%, respectively (p less than 0.001). Patients presenting with a placenta previa and a scarred uterus had a 16% risk of undergoing cesarean hysterectomy because of placenta accreta and severe hemorrhage compared to 3.6% in patients with placenta previa and an unscarred uterus. In conclusion, cesarean deliveries predispose to placenta previa, placenta accreta and antepartum hemorrhage during subsequent pregnancies. This relationship has to be considered in the cost-benefit equation for decision of route of delivery.     

Bleeding complications in pregnancies with low-lying placenta

Objective: To evaluate pregnancy outcomes with low-lying placenta according to the distance from placenta to cervical os.

Methods: Retrospective cohort study of singleton pregnancies with low-lying placenta (placenta edge within 20?mm of internal os on transvaginal sonography) delivered at our hospital from 2002 to 2012, excluding suspected placenta accreta and vasa previa. Vaginal delivery was offered in the absence of another indication for cesarean. Outcomes were stratified according to placenta-os distance ≤10?mm and 11–20?mm.

Results: Of 98 pregnancies with low-lying placenta, 41% had placenta-os distance ≤10?mm and 59% placenta-os distance 11–20?mm. Fifty-four percent had a trial of labor. Six (15%) with placenta-os ≤10?mm and 21 (36%) with placenta-os 11–20?mm delivered vaginally, p?=?0.02. Bleeding necessitating cesarean occurred in 25%, and postpartum hemorrhage in 43%; neither complication associated with placenta-os distance. Third-trimester bleeding prior to delivery hospitalization was reported in 44% and associated with later bleeding requiring cesarean in 51% versus 4% of those without third-trimester bleeding, p?<?0.001.

Conclusion: Whereas low-lying placenta does not contraindicate labor, we found significant risk for bleeding complications, regardless of the planned mode of delivery. Placenta-os distance did not significantly affect outcomes in our series.