SMFM Abstracts S239
Volume 189, Number 6 Am J Obstet Gynecol 663
DOES THE INCIDENCE OF TWO-VESSEL CORD CORRELATE WITH AN INCREASED INCIDENCE OF DISCORDANCE IN TWIN GESTATIONS? PAUL MATTA1, EDMUND FUNAI2, JOSHUA COPEL3, KEITH WILLIAMS3, 1 Yale University, Obstetrics and Gynecology, New Haven, CT 2Yale University, Obstetrics and Gynecology, New Haven, CT 3Yale University, Obstetrics & Gynecology, New Haven, CT OBJECTIVE: To compare growth discordance rates in twins with 2-vessel cord versus those with a normal 3-vessel cord. STUDY DESIGN: This is a retrospective hospital-based cohort study of twin pregnancies. Delivering at >34 weeks from 1995-2003 with two live neonates. Placental pathology reports were reviewed to identify those twin gestations with 2-vessel umbilical cords. From the Yale Perinatal Unit database, we obtained biometry data and calculated the incidence of twin to twin discordances of >25% in estimated fetal weight, AC, femur length, and BPD. We compared these twin discordances between the 2-vessel umbilical cord group (N = 24) and the control group (3-VC, N = 48) at the time of the targeted ultrasound (18-20 wks) and the 3rd-trimester ultrasound using odds ratio and 95% confidence intervals. RESULTS: At the time of the 2nd-trimester targeted ultrasound, there were only 2 out of 24 discordant twins (9.1%) in the 2-vessel cord group compared to 1 out of 48 (2.1%) in the control group, with an OR of 4.2 (CI 1.28-126) (P = 0.53) . At the third-trimester ultrasound the incidence of estimated fetal weight discordance was 7 out of 27 (29.2%) in the 2-vessel cord group compared to 3 out of 48 (6.3%) in the control group, with an OR of 6.2 (CI = 1.2-34.7) (P = .02). CONCLUSION: Twins with 2-vessel cord are at higher risk for growth discordance, manifested primarily in the third trimester and should be followed closely with serial ultrasounds.
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THE ACCURACY OF PRENATAL DIAGNOSIS OF FETAL HEART ANOMALIES IN THE OBESE GRAVIDA MAYRA TROYA-NUTT1, ISRAEL HENDLER2, SEAN BLACKWELL2, MARJORIE TREADWELL2, EMMANUEL BUJOLD2, ROBERT SOKOL2, YORAM SOROKIN2, 1Wayne State University, Obstetrics/Gynecology, Detroit, MI 2Wayne State University, Obstetrics/ Gynecology/MFM, Detroit, MI OBJECTIVE: To compare the accuracy of prenatal ultrasound diagnosis for major fetal heart anomalies in obese and non-obese women. STUDY DESIGN: A computerized ultrasound and perinatal database was used to identify patients who had prenatally diagnosed major heart defects and delivered a live-born neonate at $24 weeks’ (10/1999-6/2003). Prenatal ultrasound reports were compared with neonatal examination including echocardiography. Demographic data, clinical characteristics, and outcome data were collected. Patients were divided into 2 groups based on body mass index (BMI). The agreement between prenatal and postnatal diagnosis was compared between obese (BMI $30 kg/m2) and non-obese patients (BMI < 30 kg/m2). RESULTS: Nineteen neonates met all study criteria. Prenatal diagnoses included left and right hypoplastic heart, atrial septal defect (ASD), ventricular septal defect (VSD), AV canal, tetralogy of Fallot, valvular or aortic anomalies. Of these, the diagnosis was confirmed postnatally in 12 (63%) cases. However, in obese patients 75% (6 of 8) newborns were found to have a normal cardiac evaluation postnatally, while only 1 of 11 newborns had a normal cardiac evaluation in non-obese gravidas (P = 0.004). Ventricular septal defect was the most frequently overdiagnosed anomaly (4 out of 7 cases, 57.1%); 1 case of ASD, 1 coarctation of the aorta, and 1 case of asymmetry between the right and the left heart. CONCLUSION: Maternal obesity may contribute to misdiagnosis of fetal cardiac defects. This information should be considered in the counseling and management of the obese gravida with prenatally diagnosed fetal anomalies, mainly ventricular septal defects.
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SUB-OPTIMAL ULTRASOUND VISUALIZATION OF THE FETAL HEART IN OBESE PATIENTS: SHOULD WE REPEAT THE EXAM? ISRAEL HENDLER1, SEAN BLACKWELL1, MARJORIE TREADWELL1, EMMANUEL BUJOLD1, ROBERT SOKOL1, RYAN BLACKWELL2, YORAM SOROKIN1, 1 Wayne State University, Obstetrics/Gynecology/MFM, Detroit, MI 2Wayne State University, Obstetrics/Gynecology, Detroit, MI OBJECTIVE: To study whether repeat ultrasound examination improves fetal cardiac visualization in obese and non-obese gravida. STUDY DESIGN: A computerized ultrasound database (10/1999-6/2003) was used to identify initial ultrasound examinations at 18-22 weeks’ in which there was sub-optimal visualization (SV) of cardiac structures (4-chamber and outflow tracts). Patients who underwent repeat examination within 2 weeks (especially to re-evaluate cardiac structures) were analyzed. Exclusion criteria were multiple gestations, cardiac or non-cardiac anomalies, abnormal serum screening, or maternal diabetes. Patients were classified by maternal body mass index (BMI) (kg/m2): BMI < 30 (non-obese), 30 # BMI < 35 (obesity class I), 35 # BMI < 40 (obesity class II), and BMI $40 (extreme obesity) The relationship between maternal BMI and SV of the fetal heart on follow-up exam was evaluated. RESULTS: 372 patients met study criteria. Median gestational age at repeat examination was 21.4 wks (range 18.9-23.9 wks) and median maternal BMI was 32.6 kg/m2 (range 16.4-58.7 kg/m2). 64% of patients undergoing repeat exam were obese (26% class I, 17% class II, and 20% extreme obesity). The rate of persistent SV was inversely associated with the severity of maternal obesity (nonobese 1.5%, class I 12%, class II 17%, extreme obesity 20%; P < 0.0001). One patient (1/372) with BMI = 24.1 kg/m2 who had initial SV was diagnosed with a cardiac malformation (AV canal defect) at the repeat examination. CONCLUSION: In a selective ‘‘low risk’’ population, repeat ultrasound examination was able to improve prenatal diagnosis for 1 missed defect out of 372 patients. Even with repeat examination, persistent SV occurs in up to 20% of patients with extreme obesity.
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DOES SONOGRAPHERS’ EXPERIENCE IMPACT THE RATE OF SUBOPTIMAL VISUALIZATION IN THE OBESE GRAVIDA? ISRAEL HENDLER1, SEAN BLACKWELL1, MARJORIE TREADWELL1, EMMANUEL BUJOLD1, ROBERT SOKOL1, YORAM SOROKIN1, 1Wayne State University, Obstetrics/Gynecology/MFM, Detroit, MI OBJECTIVE: To assess whether sonographers’ experience impacts the rate of sub-optimal visualization (SV) of craniospinal structures at midtrimester ultrasound examination in obese and non-obese gravidas. STUDY DESIGN: A computerized ultrasound database was used to identify all initial ultrasound examinations performed at 18-24 weeks’ in singleton pregnancies from Jan 1-July 31, 2002. All examinations were performed by registered diagnostic medical sonographers (RDMSs) and supervised by MFM specialists. The rate of adequate visualization of fetal craniospinal structures was compared based on the length of RDMSs’ experience in sonography. Sonographers’ experience was classified into 4 groups: group I >15 yrs, group II 10-15 yrs, group III 5-10 yrs, and group IV < 5 yrs. Adequate craniospinal visualization required all of the following: cranium, lateral ventricles, cerebellum, cisterna magna, and spine (cervical, thoracic, lumbar, sacral). Obese (BMI $30 kg/m2) and non-obese (BMI < 30 kg/m2) patients were analyzed separately. RESULTS: 1400 patients met inclusion criteria. Median gestational age was 19.9 wks (range 18.0-23.9). The median maternal BMI was 27.7 kg/m2 (15.8-68.3 kg/m2). Median sonographers’ experience was 9 yrs (range < 1-18 yrs). 60.7% (850/1400) were non-obese and 39.3% (550/1400) were obese. There was a significant difference in the rate of SV of craniospinal structures based on sonographers’ experience (see Table). CONCLUSION: Higher rates of adequate visualization of fetal craniospinal structures in both obese and non-obese patients were associated with greater sonographers’ experience. Visualization of fetal craniospinal structures is adversely impacted by maternal obesity, even for the most experienced sonographers. Sonographers’ experience and SV rate Gr. I >15 y Gr. II 10-15 y Gr. III 5-10 y Gr. IV < 5 y P value Non-obese Obese P value
14.7% 26.6% 0.005
21.2% 30% 0.02
29% 35.3% 0.13
27.5% 50.7% 0.001
0.002 0.003