Carri R. Warshak

Accuracy of ultrasonography and magnetic resonance imaging in the diagnosis of placenta accreta

BACKGROUND: The incidence of placenta accreta has increased dramatically over the last three decades, in concert with the increase in the cesarean delivery rate. Optimal management requires accurate prenatal diagnosis. The purpose of this study was to determine the precision and reliability of ultrasonography and magnetic resonance imaging (MRI) in diagnosing placenta accreta. METHODS: A historical cohort study was performed with information gathered from our obstetric, radiologic, and pathology databases. Records from January 2000 to June 2005 were reviewed to identify patients with a diagnosis of placenta previa, low-lying placenta with a prior cesarean delivery, or history of a myomectomy to determine the accuracy of pelvic ultrasonography in the diagnosis of placenta accreta. The records of those considered to be suspicious for placenta accreta and subsequently referred for additional confirmation by MRI were also analyzed. The sonographic and MRI diagnoses were compared with the final pathologic or operative findings or with both. RESULTS: Of the 453 women with placenta previa, previous cesarean delivery and low-lying anterior placenta, or previous myomectomy, 39 had placenta accreta confirmed by pathological examination. Ultrasonography accurately predicted placenta accreta in 30 of 39 of women and correctly ruled out placenta accreta in 398 of 414 without placenta accreta (sensitivity 0.77, specificity 0.96). Forty-two women underwent MRI evaluation because of findings suspicious or inconclusive of placenta accreta by ultrasonography. Magnetic resonance imaging accurately predicted placenta accreta in 23 of 26 cases with placenta accreta and correctly ruled out placenta accreta in 14 of 14 (sensitivity 0.88, specificity 1.0). CONCLUSION: A two-stage protocol for evaluating women at high risk for placenta accreta, which uses ultrasonography first, and then MRI for cases with inconclusive ultrasound features, will optimize diagnostic accuracy. LEVEL OF EVIDENCE: II-3

The frequency and severity of placental findings in women with preeclampsia are gestational age dependent

OBJECTIVE The purpose of this study was to evaluate placental lesions found in women with preeclampsia compared with normotensive control subjects and to determine whether the presence of these lesions are related to gestational age at delivery. STUDY DESIGN Placental disease of women with preeclampsia at 24 to 42 weeks of gestation was compared with the placental disease of normotensive gestational age-matched control subjects. The placental lesions that were studied specifically included decidual arteriolopathy, thrombi in the fetal circulation, central infarction, intervillous thrombi, and hypermaturity of villi. Data analysis involved the chi(2) test, the Student t test, and logistic regression; odds ratios and CIs were estimated. RESULTS Placentas from women with preeclampsia (n=158) and normotensive control subjects (n=156) were evaluated. Among women with preeclampsia, 67% had severe disease. Placental lesions were studied according to gestational age at delivery: <28, 28 to 32, 33 to 36, and >or=37 weeks of gestation. Of the placental lesions that were studied, decidual arteriolopathy (odds ratio, 23.8, 95% CI 10.0-57.0), hypermaturity of villi (odds ratio, 12.4; 95% CI 5.3-29.2), intervillous thrombi (odds ratio, 1.95;95% CI 1.0-3.7), central infarction (odds ratio, 5.9; 95% CI 3.1-11.1), and thrombi in the fetal circulation (odds ratio, 2.8; 95% CI 1.2-6.6) were found to have significantly higher rates in the preeclamptic group. In contrast, the rate of chorioamnionitis was significantly lower in the preeclamptic group (odds ratio, 0.2; 95% CI 0.1-0.4). The rates of abruptio placentae and meconium staining were not different between the two groups. Within the preeclamptic group, the rates of decidual arteriolopathy (P<.0001), central infarction (P=.0001), and hypermaturity of villi (P<.0001) were higher the earlier the gestational age at delivery. CONCLUSION Placentas in women with preeclampsia have increased amounts of disease. The rate is increased with lower gestational ages at the time of delivery for women with preeclampsia.

Effect of predelivery diagnosis in 99 consecutive cases of placenta accreta.

OBJECTIVE: To estimate the effects of prenatal diagnosis and delivery planning on outcomes in patients with placenta accreta. METHODS: A review was performed of all patients with pathologically confirmed placenta accreta at the University of California, San Diego Medical Center from January 1990 to April 2008. Cases were divided into those with and without predelivery diagnosis of placenta accreta. Patients with prenatal diagnosis of placenta accreta were scheduled for planned en bloc hysterectomy without removal of the placenta at 34–35 weeks of gestation after betamethasone administration. Maternal and neonatal outcomes were assessed. RESULTS: Ninety-nine women with placenta accreta were identified, of whom 62 were diagnosed before delivery and 37 were diagnosed intrapartum. Comparing women with predelivery diagnosis with those diagnosed at the time of delivery, there were fewer units of packed red blood cells transfused (4.7±2.2 compared with 6.9±1.8 units, P=.02) and a lower estimated blood loss (2,344±1.7 compared with 2,951±1.8 mL, P=.053), although this trend did not reach statistical significance. Comparison of neonatal outcomes demonstrated a higher rate of steroid administration (65% compared with 16%, P≤.001), neonatal admission to the neonatal intensive care unit (NICU) (86% compared with 60%, P=.005), and longer neonatal hospital stays (10.7±1.9 compared with 6.9±2.1 days, P=.006). Length of NICU stay, rates of respiratory distress syndrome, and surfactant administration did not differ between the groups. CONCLUSION: Predelivery diagnosis of placenta accreta is associated with decreased maternal hemorrhagic morbidity. Planned delivery at 34–35 weeks of gestation in this cohort did not significantly increase neonatal morbidity. LEVEL OF EVIDENCE: II

The effect of maternal obesity on the rate of failed induction of labor.

OBJECTIVE The purpose of this study was to quantify the relationship between class of obesity and rate of failed induction of labor. STUDY DESIGN Using the Ohio Department of Healths birth certificate database from January 1, 2006, through December 31, 2007, we performed a population-based cohort study that compared failed induction of labor rates between obese and normal-weight women. RESULTS The rate of induction is associated with increasing body mass index from 28% in normal-weight women to 34% in class III obese women (body mass index, ≥40 kg/m2). Induction failure rates are also associated with increasing obesity class from 13% in normal-weight women to 29% in class III obese women. Women with class III obesity without a previous vaginal delivery and a macrosomic fetus had the highest rate of failed induction at 80%. CONCLUSION Obesity is associated with an increased risk of failed labor induction that appears to be related directly to increasing class of obesity.

Preoperative intravascular balloon catheters and surgical outcomes in pregnancies complicated by placenta accreta: a management paradox

OBJECTIVE The objective of the study was to compare outcomes between patients who did and did not receive preoperative uterine artery balloon catheters in the setting placenta accreta. STUDY DESIGN This was a retrospective case-control study of patients with placenta accreta from 1990 to 2011. RESULTS Records from 117 patients with pathology-proven accreta were reviewed. Fifty-nine patients (50.4%) had uterine artery balloons (UABs) placed preoperatively. The mean estimated blood loss (EBL) was lower (2165 mL vs 2837 mL; P = .02) for the group that had UABs compared with the group that did not. There were more cases with an EBL greater than 2500 mL and massive transfusions of packed red blood cells (>6 units) in the group that did not have UABs. Percreta was diagnosed more often on final pathology in the group with UABs. Surgical times did not differ between the 2 groups. Two patients (3.3%) had complications related to the UABs. CONCLUSION Preoperative placement of UABs is relatively safe and is associated with a reduced EBL and fewer massive transfusions compared with a group without UABs.

Increasing Maternal Body Mass Index and the Accuracy of Sonographic Estimation of Fetal Weight Near Delivery

To evaluate whether an increasing body mass index (BMI) influences the accuracy of sonographic estimation of fetal weight.

Neonatal chemical hypoglycemia in newborns from pregnancies complicated by type 2 and gestational diabetes mellitus – the importance of neonatal ponderal index

Objective. To determine the frequency and risk factors associated with neonatal chemical hypoglycemia in neonates of mothers with type 2 diabetes and gestational diabetes mellitus (GDM). Research Design and Methods. A retrospective cohort study of women with type 2 diabetes or GDM and their singleton neonates. The primary outcome measure was the presence of neonatal chemical hypoglycemia (capillary plasma equivalent glucose <45 mg/dl) within 1 h of birth. Statistical methods included bivariate and multivariate analyses. Results. 242 mother infant dyads were identified. Sixty-eight (28%) were treated with diet, 110 (46%) with glyburide, and 64 (26%) with insulin. The incidence of neonatal chemical hypoglycemia was 18% (44/242). The incidence was significantly higher in those requiring pharmacotherapy (25% vs. 3%, p < 0.001). The frequency of neonatal chemical hypoglycemia between the glyburide and insulin-treated pregnancies did not differ significantly (23% vs. 27%, p = 0.58). The frequency of neonatal chemical hypoglycemia was statistically associated with birth weight, macrosomia and ponderal index (p < 0.001). Neonatal ponderal index was the strongest predictor of hypoglycemia (adjusted Odds ratio 5.59). Conclusion. Neonatal chemical hypoglycemia occurs more frequently in infants from women with type 2 diabetes and GDM treated with glyburide or insulin. An increased neonatal ponderal index is a strong predictor of significant neonatal chemical hypoglycemia.

Effect of Post–Cesarean Delivery Oral Cephalexin and Metronidazole on Surgical Site Infection Among Obese Women: A Randomized Clinical Trial

Importance The rate of obesity among US women has been increasing, and obesity is associated with increased risk of surgical site infection (SSI) following cesarean delivery. The optimal perioperative antibiotic prophylactic regimen in this high-risk population undergoing cesarean delivery is unknown. Objective To determine rates of SSI among obese women who receive prophylactic oral cephalexin and metronidazole vs placebo for 48 hours following cesarean delivery. Design, Setting, and Participants Randomized, double-blind clinical trial comparing oral cephalexin and metronidazole vs placebo for 48 hours following cesarean delivery for the prevention of SSI in obese women (prepregnancy BMI ≥30) who had received standard intravenous preoperative cephalosporin prophylaxis. Randomization was stratified by intact vs rupture of membranes prior to delivery. The study was conducted at the University of Cincinnati Medical Center, Cincinnati, Ohio, an academic and urban setting, between October 2010 and December 2015, with final follow-up through February 2016. Interventions Participants were randomly assigned to receive oral cephalexin, 500 mg, and metronidazole, 500 mg (n = 202 participants), vs identical-appearing placebo (n = 201 participants) every 8 hours for a total of 48 hours following cesarean delivery. Main Outcomes and Measures The primary outcome was SSI, defined as any superficial incisional, deep incisional, or organ/space infections within 30 days after cesarean delivery. Results Among 403 randomized participants who were included (mean age, 28 [SD, 6] years; mean BMI, 39.7 [SD, 7.8]), 382 (94.6%) completed the trial. The overall rate of SSI was 10.9% (95% CI, 7.9%-14.0%). Surgical site infection was diagnosed in 13 women (6.4%) in the cephalexin-metronidazole group vs 31 women (15.4%) in the placebo group (difference, 9.0% [95% CI, 2.9%-15.0%]; relative risk, 0.41 [95% CI, 0.22-0.77]; P = .01). There were no serious adverse events, including allergic reaction, reported in either the antibiotic group or the placebo group. Conclusions and Relevance Among obese women undergoing cesarean delivery who received the standard preoperative cephalosporin prophylaxis, a postoperative 48-hour course of oral cephalexin and metronidazole, compared with placebo, reduced the rate of SSI within 30 days after delivery. For prevention of SSI among obese women after cesarean delivery, prophylactic oral cephalexin and metronidazole may be warranted. Trial Registration clinicaltrials.gov Identifier: NCT01194115

Influence of Adolescence and Obesity on the Rate of Stillbirth

BACKGROUND We hypothesise that the rate of stillbirth is increased in mothers younger than 18 years of age compared to adult mothers, and that obesity further increases the risk of stillbirth in this population. METHODS We conducted a population-based cohort study comparing rates of stillbirth between adolescent, defined as young women under the age of 18 and adult women. We then compared the rate of stillbirth in normal weight vs. obese adolescents. These effects were stratified according to gestational age. Log-binomial regression models were used to estimate the effect of adolescence and obesity on stillbirth risk while adjusting for important confounders. Risk ratios (RR) with 95% confidence intervals [CI]were calculated. RESULTS We reviewed data from 650 760 births in Missouri between 1998 and 2005. Stillbirth rates were 6.7 and 4.1 per 1000 in adolescents and adult women, respectively (RR 1.2, 95% CI 1.03-1.5). A higher proportion of stillbirths occurred prior to 28 weeks in adolescents vs. adults (53% vs. 37% respectively, P = 0.002). The risk of stillbirth in obese adolescents was further increased over normal weight adolescents (adjusted RR [aRR] 1.7, 95% CI 1.02-2.9). CONCLUSION Adolescent pregnancies, particularly obese adolescents, are at an increased risk of stillbirth.

The impact of fetal growth restriction on latency in the setting of expectant management of preeclampsia

BACKGROUND Fetal growth restriction is a common complication of preeclampsia. Expectant management for qualifying patients has been found to have acceptable maternal safety while improving neonatal outcomes. Whether fetal growth restriction influences the duration of latency during expectant management of preeclampsia is unknown. OBJECTIVE The objective of the study was to determine whether fetal growth restriction is associated with a reduced interval to delivery in women with preeclampsia being expectantly managed prior to 34 weeks. STUDY DESIGN We performed a retrospective cohort of singleton, live-born, nonanomalous deliveries at the University of Cincinnati Medical Center between 2008 and 2013. Patients were included in our analysis if they were diagnosed with preeclampsia prior to 34 completed weeks and if the initial management plan was to pursue expectant management beyond administration of steroids for fetal lung maturity. Two study groups were determined based on the presence or absence of fetal growth restriction. Patients were delivered when they developed persistent neurological symptoms, severe hypertension refractory to medical therapy, renal insufficiency, nonreassuring fetal status, pulmonary edema, or hemolysis elevated liver low platelet syndrome or when they reached 37 weeks if they remained stable without any other indication for delivery. Our primary outcome was the interval from diagnosis of preeclampsia to delivery, measured in days. Secondary outcomes included indications for delivery, rates of induction and cesarean delivery, development of severe morbidities of preeclampsia, and select neonatal outcomes. We performed a multivariate logistic regression analysis comparing those with fetal growth restriction with those with normally grown fetuses to determine whether there is an association between fetal growth restriction and a shortened interval to delivery, neonatal intensive care unit admission, prolonged neonatal stay, and neonatal mortality. RESULTS A total of 851 patients met the criteria for preeclampsia, of which 199 met inclusion criteria, 139 (69%) with normal growth, and 60 (31%) with fetal growth restriction. Interval to delivery was significantly shorter in women with fetal growth restriction, median (interquartile range) of 3 (1.6) days vs normal growth, 5 (2.12) days, P < .001. The association between fetal growth restriction and latency less than 7 days remained significant, even after post hoc analysis controlling for confounding variables (adjusted odds ratio, 1.66 [95% confidence interval, 1.12-2.47]). There were no differences in the development of severe disease (85.9 vs 91.7%, P = .26), need for intravenous antihypertensive medications (47.1 vs 46.7%, P = .96), and the development of severe complications of preeclampsia (51.1 vs 42.9%, P = .30) in normally grown and growth-restricted fetuses, respectively. Fewer women with fetal growth restriction attained their scheduled delivery date, 3 of 60 (5.0%), compared with normally grown fetuses,12 of 139 (15.7%), P = .03. Admission to the neonatal intensive care unit, neonatal length of stay, and neonatal mortality were higher when there was fetal growth restriction; however, after a logistic regression analysis, these associations were no longer significant. CONCLUSION Fetal growth restriction is associated with a shortened interval to delivery in women undergoing expectant management of preeclampsia when disease is diagnosed prior to 34 weeks. These data may be helpful in counseling patients regarding the expected duration of pregnancy, guiding decision making regarding administration of steroids and determining the need for maternal transport.