Martin R. Chavez

Recurrence of Ischemic Placental Disease

OBJECTIVE: To test the hypothesis that the presence of preeclampsia, small for gestational age (SGA)-birth, and placental abruption in the first pregnancy confers increased risk in the second pregnancy. METHODS: A retrospective cohort study entailing a case–crossover analysis was performed based on women who had two consecutive singleton live births (n=154,810) between 1989 and 1997 in Missouri. Small for gestational age was defined as infants with birth weight below the 10th centile for gestational age. Risk and recurrence of ischemic placental disease was assessed from fitting logistic regression models after adjusting for several confounders. RESULTS: Preeclampsia in the first pregnancy was associated with significantly increased risk of preeclampsia (odds ratio 7.03, 95% confidence interval 6.51, 7.59), SGA (odds ratio 1.16, 95% confidence interval 1.06, 1.27), and placental abruption (odds ratio 1.90, 95% confidence interval 1.51, 2.38) in the second pregnancy. Similarly, women with SGA and abruption in the first pregnancy were associated with increased risks of all other conditions in the second pregnancy. CONCLUSION: Women with preeclampsia, SGA, and placental abruption in their first pregnancy—conditions that constitute ischemic placental disease—are at substantially increased risk of recurrence of any or all these conditions in their second pregnancy. Although causes of these conditions remain largely speculative, these entities may manifest through a common pathway of ischemic placental disease with significant risk of recurrence. LEVEL OF EVIDENCE: II

Primary Preeclampsia in the Second Pregnancy : Effects of Changes in Prepregnancy Body Mass Index Between Pregnancies

OBJECTIVE: To examine the association between changes in prepregnancy body mass index (BMI) between a woman’s first two pregnancies and incidence of preeclampsia in the second pregnancy. METHODS: We performed a population-based retrospective cohort analysis using data on women’s first two singleton pregnancies (n=136,884) in Missouri (1989–1997). The study was restricted to women without preeclampsia in the first pregnancy. Prepregnancy BMI (kg/m2) was categorized as underweight (less than 18.5), normal (18.5–24.9), overweight (25–29.9), and obese (30 or greater). Analyses were adjusted for confounders through multivariable logistic regression. RESULTS: The incidence rate of preeclampsia in the second pregnancy was 2.0%. In comparison with women who were of normal BMI in both pregnancies, the risk for preeclampsia increased when BMI changed between the first two pregnancies from underweight to obese (odds ratio [OR] 5.6, 95% confidence interval [CI] 1.7–18.2), normal to overweight (OR 2.0, 95% CI 1.7–2.3), normal to obese (OR 3.2, 95% CI 2.5–4.2), and overweight to obese (OR 3.7, 95% CI 3.1–4.3). Being obese or overweight in both pregnancies was associated with increased risk of preeclampsia in the second pregnancy. Women who increased their BMI from underweight to normal or overweight between pregnancies had risks of preeclampsia comparable with those with normal BMI in both pregnancies. African-American, but not white, women who had a reduction in BMI from obese or overweight to normal between pregnancies remained at increased risk for preeclampsia. CONCLUSION: Increases in prepregnancy BMI from normal weight to overweight or obese between pregnancies are associated with increased risk of preeclampsia in the subsequent pregnancy. LEVEL OF EVIDENCE: II

Patient acceptance of non-invasive testing for fetal aneuploidy via cell-free fetal DNA

Abstract Objective: To evaluate factors associated with patient acceptance of noninvasive prenatal testing for trisomy 21, 18 and 13 via cell-free fetal DNA. Methods: This was a retrospective study of all patients who were offered noninvasive prenatal testing at a single institution from 1 March 2012 to 2 July 2012. Patients were identified through our perinatal ultrasound database; demographic information, testing indication and insurance coverage were compared between patients who accepted the test and those who declined. Parametric and nonparametric tests were used as appropriate. Significant variables were assessed using multivariate logistic regression. The value p < 0.05 was considered significant. Results: Two hundred thirty-five patients were offered noninvasive prenatal testing. Ninety-three patients (40%) accepted testing and 142 (60%) declined. Women who accepted noninvasive prenatal testing were more commonly white, had private insurance and had more than one testing indication. There was no statistical difference in the number or the type of testing indications. Multivariable logistic regression analysis was then used to assess individual variables. After controlling for race, patients with public insurance were 83% less likely to accept noninvasive prenatal testing than those with private insurance (3% vs. 97%, adjusted RR 0.17, 95% CI 0.05–0.62). Conclusion: In our population, having public insurance was the factor most strongly associated with declining noninvasive prenatal testing.

Practice patterns in the timing of antenatal corticosteroids for fetal lung maturity

Abstract Objective: To determine the practice patterns of antenatal corticosteroid (AS) administration in women with threatened preterm labor. Methods: This was a retrospective cohort of patients who received betamethasone between 2009 and 2010, identified through a pharmacy database. Patients with high order multiples; incomplete records and indicated preterm delivery were excluded. Demographic and obstetrical factors were compared between women with an AS to delivery latency of ≤7 days versus >7 days. Parametric and non-parametric tests were used as appropriate. p < 0.05 denotes statistical significance; relative risks with 95% confidence intervals were calculated. Results: Three-hundred forty-five patients were included. Sixty-eight patients (20%) received AS within 7 days of delivery. Women who received AS ≤7 days before delivery (optimal timing) were more likely to have a transvaginal cervical length ≤2 cm (RR:2.53, CI: 1.2–5.6), cervical dilation ≥2 cm (RR: 3.86, CI: 2.7–5.6) and positive fFN (RR: 2.59, CI: 1.1–6.3). Preterm premature ruptured membranes were also associated with optimal timing of AS (RR: 4.86, CI: 3.4–6.8). Conclusions: Eighty percent of patients receive suboptimal timing of AS administration. Factors associated with suboptimal timing are: cervical length >2 cm, cervical dilation <2 cm and negative fFN. Cervical assessment should be a key factor in the decision for AS administration. More research is needed for accurate timing of AS in women with threatened preterm labor.

First-Trimester Sonographic Prediction of Obstetric and Neonatal Outcomes in Monochorionic Diamniotic Twin Pregnancies

The purpose of this study was to investigate whether discordant nuchal translucency and crown‐rump length measurements in monochorionic diamniotic twins are predictive of adverse obstetric and neonatal outcomes.

Effectiveness and short-term safety of modified sodium hyaluronic acid-carboxymethylcellulose at cesarean delivery: a randomized trial.

BACKGROUND The rising cesarean birth rate has drawn attention to risks associated with repeat cesarean birth. Prevention of adhesions with adhesion barriers has been promoted as a way to decrease operative difficulty. However, robust data demonstrating effectiveness of such interventions are lacking. OBJECTIVE We report data from a multicenter trial designed to evaluate the short-term safety and effectiveness of a modified sodium hyaluronic acid (HA)-carboxymethylcellulose (CMC) absorbable adhesion barrier for reduction of adhesions following cesarean delivery. STUDY DESIGN Patients who underwent primary or repeat cesarean delivery were included in this multicenter, single-blinded (patient), randomized controlled trial. Patients were randomized into either HA-CMC (N = 380) or no treatment (N = 373). No other modifications to their treatment were part of the protocol. Short-term safety data were collected following randomization. The location and density of adhesions (primary outcome) were assessed at their subsequent delivery using a validated tool, which can also be used to derive an adhesion score that ranges from 0-12. RESULTS No differences in baseline characteristics, postoperative course, or incidence of complications between the groups following randomization were noted. Eighty patients from the HA-CMC group and 92 controls returned for subsequent deliveries. Adhesions in any location were reported in 75.6% of the HA-CMC group and 75.9% of the controls (P = .99). There was no significant difference in the median adhesion score; 2 (range 0-10) for the HA-CMC group vs 2 (range 0-8) for the control group (P = .65). One third of the HA-CMC patients met the definition for severe adhesions (adhesion score >4) compared to 15.5% in the control group (P = .052). There were no significant differences in the time from incision to delivery (P = .56). Uterine dehiscence in the next pregnancy was reported in 2 patients in HA-CMC group vs 1 in the control group (P = .60). CONCLUSION Although we did not identify any short-term safety concerns, HA-CMC adhesion barrier applied at cesarean delivery did not reduce adhesion formation at the subsequent cesarean delivery.

Revisiting Ectopic Pregnancy: A Pictorial Essay

Ectopic pregnancies occur in approximately 1.4% of all pregnancies and account for 15% of pregnancy-related deaths. Considering the high degree of mortality, recognizing an ectopic pregnancy is important. Signs and symptoms of an ectopic pregnancy are nonspecific and include pain, vaginal bleeding, and an adnexal mass. Therefore, imaging can play a critical role in diagnosis. There are different types of ectopic pregnancies, which are tubal, cornual, cesarean scar, cervical, heterotopic, abdominal, and ovarian. Initial imaging evaluation of pregnant patients with pelvic symptoms is by ultrasonography, transabdominal, transvaginal or both. We review the sonographic appearance of different types of ectopic pregnancies that will aid in accurate and prompt diagnosis.

Does educational intervention affect resident competence in sonographic cervical length measurement

Abstract Objective: To determine if a structured teaching module improves resident competency in transvaginal sonographic cervical length measurements. Methods: This was a prospective cohort study involving obstetrics and gynecology residents at a single institution. Residents collected 10 transvaginal cervical images from patients with threatened preterm labor presenting to Labor and Delivery. After initial image acquisition, residents participated in a lecture-based teaching module involving a pre- and post-intervention assessment. Following the didactic session, they collected 10 additional images. All the images were scored independently by two Maternal–Fetal Medicine attending physicians based on the quality and accuracy of the measured cervical length. Pre-and post- intervention test results were compared, as well as pre- and post- intervention image scores. Parametric and nonparametric tests were used as appropriate with p < 0.05 considered significant. Results: Ninety-three percent of the residents (14/15) improved their scores from pre-test to post-test or maintained an already perfect score (p < 0.01). Improvement was most significant with the junior residents. Seventy-nine percent of the residents (11/14) improved their cervical image scores after the educational session. Mean score for total residents was 73.7 + 12.6 pre-intervention and 90.2 + 9.9 post-intervention (p < 0.01) out of a total of 120. Conclusions: There is an improvement in the competence of resident measured cervical lengths via transvaginal ultrasound when a structured educational module is implemented for resident education.

Improving the ultrasound detection of isolated fetal limb abnormalities

Abstract Objective: The prenatal detection rate of isolated fetal limb abnormalities ranges from 4 to 29.5%. Our aim was to determine the accuracy of a detailed ultrasound protocol in detecting isolated fetal limb abnormalities Methods: This is a retrospective study of infants born at our institution with isolated limb defects from 2009 to 2014. Antepartum and postpartum records were reviewed for genetic testing results. We routinely image both upper and lower extremities, including all long bones, hands, feet, fingers and toes. Posturing, muscular tone and movement are also noted. Results: During the study period, there were 52 neonates born with isolated fetal limb abnormalities who had received a fetal anatomic survey in our ultrasound unit and 15 930 sonograms performed with normal findings; 36 out of the 52 had been prenatally diagnosed (detection rate 69%). The specificity of the protocol was 100% as there were no false positive cases, the positive predictive value was 100% and negative predictive value 99.8%. Forty-three of 52 neonates had normal genetic testing either prenatally or postnatally; 9 neonates did not undergo genetic testing. The average additional time required for this detailed protocol was <5 min for second trimester sonogram. Conclusion: A minimal investment in time for detailed evaluation of fetal limbs more than doubles the previously reported prenatal detection rate.

Ultrasound-guided manipulation of fetal entrapment by a large uterine fibroid

FIGURE 2 Dolichocephalic fetus preprocedure Case notes A 34-year-old G2P0010 presents for nuchal translucency at 12 weeks’ gestation. Ultrasound revealed a dolichocephalic fetus (cephalic index of 49) (Figure 1). This was attributed to fetal “entrapment” secondary to compartmentalization of the fetus superiorly due to an anterior, submucosal myoma (8.8 9.4 8.0 cm) separating it inferiorly from the placenta and amniotic fluid (Figure 2). Nuchal translucency could not be measured