Obstetric and gynecologic ultrasound curriculum and competency assessment in residency training programs: consensus report.

Ultrasound imaging has become integral to the practice of obstetrics and gynecology. With increasing educational demands and limited hours in residency programs, dedicated time for training and achieving competency in ultrasound has diminished substantially. The American Institute of Ultrasound in Medicine assembled a multi-Society Task Force to develop a consensus-based, standardized curriculum and competency assessment tools for obstetric and gynecologic ultrasound training in residency programs. The curriculum and competency-assessment tools were developed based on existing national and international guidelines for the performance of obstetric and gynecologic ultrasound examinations and thus are intended to represent the minimum requirement for such training. By expert consensus, the curriculum was developed for each year of training, criteria for each competency assessment image were generated, the pass score was established at or close to 75% for each, and obtaining a set of five ultrasound images with pass score in each was deemed necessary for attaining each competency. Given the current lack of substantial data on competency assessment in ultrasound training, the Task Force expects that the criteria set forth in this document will evolve with time. The Task Force also encourages use of ultrasound simulation in residency training and expects that simulation will play a significant part in the curriculum and the competency-assessment process. Incorporating this training curriculum and the competency-assessment tools may promote consistency in training and competency assessment, thus enhancing the performance and diagnostic accuracy of ultrasound examination in obstetrics and gynecology. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Improved technical success, postnatal outcome and refined predictors of outcome for fetal aortic valvuloplasty.

OBJECTIVES: Fetal aortic valvuloplasty (FAV) may prevent progression of mid-gestation aortic stenosis to hypoplastic left heart syndrome (HLHS). The aim of this study was to evaluate whether technical success and biventricular (Biv) outcome after FAV have changed from an earlier (2000-2008) to a more recent (2009-2015) era and identify pre-FAV predictors of Biv outcome. METHODS: We evaluated procedural and postnatal outcomes in 123 fetuses that underwent FAV for evolving HLHS at Boston Children's Hospital between 2000 and 2015. The primary outcome measure was circulation type (Biv vs single ventricle) at the time of neonatal hospital discharge. Classification and regression tree (CART) analysis was performed to construct a stratification algorithm to predict Biv circulation based on pre-FAV fetal variables. RESULTS: The FAV procedure was technically successful in 101/123 (82%) fetuses, with a higher technical success rate in the more recent era than in the earlier one (49/52 (94%) vs 52/71 (73%); P = 0.003). In liveborn patients, the incidence of Biv outcome was higher in the recent than in the earlier era, both in the entire liveborn cohort (29/49 (59%) vs 16/62 (26%); P = 0.001) and in those in whom the procedure was technically successful (27/46 (59%) vs 15/47 (32%); P = 0.007). Independent predictors of Biv outcome were higher left ventricular (LV) pressure, larger ascending aorta, better LV diastolic function and higher LV long-axis Z-score. On CART analysis, fetuses with LV pressure > 47 mmHg and ascending aorta Z-score ≥ 0.57 had a 92% probability of Biv outcome (n = 24). Those with a lower LV pressure, or mitral dimension Z-score < 0.1 and mitral valve inflow time Z-score < -2 (n = 34) were unlikely to have Biv (probability of 9%). The remainder of the patients had an intermediate (∼40-60%) likelihood of Biv circulation. CONCLUSIONS: The proportion of patients achieving Biv outcome after FAV has increased, probably owing to an improved technical success rate and modified selection criteria. Fetal factors, including LV pressure, size of the ascending aorta and diastolic function, are associated with likelihood of Biv circulation after FAV. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Changes in left heart hemodynamics after technically successful in-utero aortic valvuloplasty.

OBJECTIVE: Severe aortic stenosis in the mid-gestation fetus can progress to hypoplastic left heart syndrome (HLHS). @ In-utero aortic valvuloplasty is an innovative therapy to promote left ventricular growth and function and potentially to prevent HLHS. This study evaluated the effects of mid-gestation fetal balloon aortic valvuloplasty on subsequent fetal left ventricular function and left heart Doppler characteristics. METHODS: We reviewed fetuses with aortic stenosis that underwent attempted in-utero aortic valvuloplasty between 2000 and 2006. Pre-intervention and the latest post-intervention fetal echocardiograms were analyzed to characterize changes in left heart function and Doppler characteristics in utero. RESULTS: Forty-two fetuses underwent attempted aortic valvuloplasty during the study period, 12 of which were excluded from analysis secondary to inadequate follow-up data, termination or fetal demise. Study fetuses (n = 30) underwent pre-intervention echocardiography at a median gestational age of 23 weeks, and were followed for a median of 66 +/- 23 days post-intervention. In 26 fetuses, aortic valvuloplasty was technically successful. Among these 26, left heart physiology was abnormal pre-intervention and improved or normalized after intervention in most cases: biphasic mitral inflow was present in 5/25 (20%) cases pre-intervention and in 21/23 (91%) post-intervention (P < 0.001); moderate or severe mitral regurgitation was present in 14/26 (54%) cases pre-intervention and in 5/23 (22%) post-intervention (P = 0.02); bidirectional flow across the patent foramen ovale was present in 0/26 cases pre-intervention and in 6/25 (24%) post-intervention (P = 0.01); antegrade flow in the transverse arch was present in 0/25 cases pre-intervention and in 17/26 (65%) post-intervention (P < 0.001). The left ventricular ejection fraction increased from 19 +/- 10% pre-intervention to 39 +/- 14% post-intervention (P < 0.001). These changes were not observed in control fetuses (n = 18). CONCLUSION: Fetal aortic valvuloplasty, when technically successful, improves left ventricular systolic function and left heart Doppler characteristics.

Factors affecting technical success of fetal aortic valve dilation.

OBJECTIVE: We have reported previously that valve dilation enhances growth of cardiac structures and may prevent hypoplastic left heart syndrome (HLHS) in fetuses with critical aortic stenosis. We aimed to investigate maternal/fetal factors which may affect the technical success of fetal valvuloplasty, and to describe perinatal complications of the procedure. METHODS: This was a descriptive series of 22 fetuses diagnosed with critical aortic stenosis developing into HLHS which underwent intervention by valvuloplasty. Initially this was attempted using a percutaneous approach; reassessment after our first five attempts, only one of which was successful, led to the introduction of the option of laparotomy. Technical success was defined as balloon inflation across the aortic annulus and a broader jet through the aortic valve as assessed by Doppler. Data collected included body mass index, demographic variables, ultrasound findings and postprocedure interventions. RESULTS: Technical success increased significantly if maternal laparotomy was an option (83.3% vs. 20.0%, P = 0.017). Laparotomy was performed in 66.6% (12/18) of cases. There was a learning curve that showed an increase in success rate and decrease in need for laparotomy over the 3-year study period. Neither the need for laparotomy nor the chances of technical success were predictable by gestational age, body mass index or placental location. Tocolysis was limited to perioperative prophylaxis; one woman experienced wound infection and fluid overload. Postoperatively, three fetuses died and two delivered prematurely, 2 and 7 weeks after intervention. CONCLUSION: Fetal aortic valvuloplasty can be performed with technical success, with low fetal loss rate and few maternal complications. While the need for laparotomy cannot be predicted, having it available as an option improves the technical success rate.

Evaluation of the woman with postmenopausal bleeding: Society of Radiologists in Ultrasound-Sponsored Consensus Conference statement.

OBJECTIVES: A panel of 14 physicians practicing medicine in the United States with expertise in radiology, obstetrics and gynecology, gynecologic oncology, hysteroscopy, epidemiology, and pathology was convened by the Society of Radiologists in Ultrasound to discuss the role of sonography in women with postmenopausal bleeding. Broad objectives of this conference were (1) to advance understanding of the utility of different diagnostic techniques for evaluating the endometrium in women with postmenopausal bleeding; (2) to formulate useful and practical guidelines for evaluation of women with postmenopausal bleeding, specifically as it relates to the use of sonography; and (3) to offer suggestions for future research projects. SETTING: October 24 and 25, 2000, Washington, DC, preceding the annual Society of Radiologists in Ultrasound Advances in Sonography conference. PROCEDURE: Specific questions to the panel included the following: (1) What are the relative effectiveness and cost-effectiveness of using transvaginal sonography versus office (nondirected) endometrial biopsy as the initial examination for a woman with postmenopausal bleeding? (2) What are the sonographic standards for evaluating a woman with postmenopausal bleeding? (3) What are the abnormal sonographic findings in a woman with postmenopausal bleeding? (4) When should saline infusion sonohysterography or hysteroscopy be used in the evaluation of postmenopausal bleeding? (5) Should the diagnostic approach be modified for patients taking hormone replacement medications, tamoxifen, or other selective estrogen receptor modulators? CONCLUSIONS: Consensus recommendations were used to create an algorithm for evaluating women with postmenopausal bleeding. All panelists agreed that because postmenopausal bleeding is the most common presenting symptom of endometrial cancer, when postmenopausal bleeding occurs, clinical evaluation is indicated. The panelists also agreed that either transvaginal sonography or endometrial biopsy could be used safely and effectively as the first diagnostic step. Whether sonography or endometrial biopsy is used initially depends on the physician's assessment of patient risk, the nature of the physician's practice, the availability of high-quality sonography, and patient preference. Similar sensitivities for detecting endometrial carcinoma are reported for transvaginal sonography when an endometrial thickness of greater than 5 mm is considered abnormal and for endometrial biopsy when "sufficient" tissue is obtained. Currently, with respect to mortality, morbidity, and quality-of-life end points, there are insufficient data to comment as to which approach is more effective. The conference concluded by identifying several important unanswered questions and suggestions that could be addressed by future research projects.

Sonographic and Doppler characteristics of the corpus luteum: can they predict pregnancy outcome?

OBJECTIVE: To determine whether there is a relationship between gray scale or Doppler characteristics of the corpus luteum and first-trimester pregnancy outcome. METHODS: We conducted a prospective study of patients with spontaneous singleton pregnancies between 5 and 8 weeks' gestation. The corpus luteum size, sonographic appearance, resistive index, and peak systolic velocity were measured on transvaginal sonography. Maternal use of exogeneous progesterone was recorded. Only patients with known first-trimester outcome were included. RESULTS: There were 201 study patients. The corpus luteum could be visualized in 197 (98%) and had a mean +/- SD size of 1.9 +/- 0.6 cm, a mean resistive index of 0.50 +/- 0.08, and a peak systolic velocity of 20.5 +/- 11.2 cm/s. There were 151 first-trimester survivors (75.1 %) and 50 spontaneous losses (24.9%). In a comparison of the survivors and losses, there was no significant difference in mean corpus luteum size (1.9 versus 1.7 cm; P = .10, t test), mean resistive index (0.50 versus 0.50; P = .71, t test), peak systolic velocity (21 versus 19 cm/s; P = .29, t test), or sonographic appearance (P = .78, chi2 test). The lack of association between corpus luteum characteristics and outcome persisted when cases were stratified by progesterone use and the presence or absence of a heartbeat on the study sonogram. CONCLUSION: There is no apparent relationship between the characteristics of the corpus luteum and first-trimester pregnancy outcome.

Outcome of pregnancies in women with uterine leiomyomas identified by sonography in the first trimester.

PURPOSE: We assessed the outcome of pregnancies in women with uterine leiomyomas (fibroids) documented by sonography in the first trimester of pregnancy. METHODS: We collected cases of women who had undergone first-trimester sonography and had uterine fibroids and singleton pregnancies with documented fetal heartbeats. We compared pregnancy loss rates and modes of delivery in these cases to a maternal-age-matched and gestational-age-matched control group of women who had normal uteruses and first-trimester pregnancies with documented fetal heartbeats. Sonograms in patients with fibroids were reviewed to determine the number of fibroids, their sizes, and their locations. Within the group of patients with fibroids, the pregnancy loss rate was also compared based on the number of fibroids and fibroid size and location. RESULTS: Our study population consisted of 143 women with leiomyomas, and our control group comprised 715 patients with a normal uterus. Among patients with fibroids, 14.7% of pregnancies resulted from assisted conception; in the control group, 6.4% of pregnancies resulted from assisted conception. The rate of spontaneous pregnancy loss in women with fibroids was almost twice the rate in women with normal uteruses (14.0% versus 7.6%; p < 0.05), and the loss rate was higher in women with multiple fibroids than in women with a single leiomyoma (23.6% versus 8.0%, p < 0.05). The loss rate was not significantly associated with fibroid size or location. The rate of cesarean-section delivery was higher in patients with fibroids than in patients with normal uteruses (38% versus 28%, p < 0.05). CONCLUSIONS: Uterine fibroids are associated with an elevated risk of spontaneous pregnancy loss. The loss rate is higher in patients with multiple fibroids than with a single fibroid. The cesarean-section rate is also higher in patients with fibroids than in patients with a normal uterus.

Frequency of a monochorionic pair in multiple gestations: relationship to mode of conception.

OBJECTIVE: To determine whether the mode of conception affects the frequency of monochorionicity in multiple gestations. METHODS: Our study population consisted of all women with multiple gestations who had a first-trimester sonogram at our institution between May 1998 and April 2000. The frequency of monochorionicity in pregnancies conceived naturally was compared with the frequency in pregnancies achieved via any form of assisted reproductive technology and among the different types of assisted reproductive technology. RESULTS: Our study consisted of 464 multiple gestations comprising 332 twin, 113 triplet, 16 quadruplet, and 3 quintuplet pregnancies. The higher the fetal number, the more likely the pregnancy resulted from assisted reproductive technology (72.6% of twins, 84.1% of triplets, 92.8% of quadruplets, and 100% of quintuplets; P < .05, Fisher exact test). Monochorionic pairs were found more commonly in naturally conceived pregnancies than in those resulting from assisted reproductive technology (28.2% versus 5.4%; P < .000001, chi2 test). The frequency of monochorionic pairs after in vitro fertilization with blastocyst transfer on day 5 (10.5%) was double the frequency from in vitro fertilization with cleavage stage transfer on day 3 (4.9%), but the difference was not statistically significant (P = .24, Fisher exact test). CONCLUSIONS: Monochorionic pairs are relatively common in naturally conceived twins and in higher-order multiple gestations with more than 3 fetuses arising from assisted reproductive technology, but they are uncommon in twins and triplets arising from assisted reproductive technology There is a trend toward a higher frequency of monochorionic pairs after day 5 blastocyst transfer than day 3 transfer, but a larger study population is needed to confirm this finding.

Postnatal outcome of fetuses with the prenatal diagnosis of asymmetric hydrocephalus.

We sought to assess the sonographic findings and postnatal outcome in fetuses with the prenatal diagnosis of asymmetric hydrocephalus. The sonograms from cases of asymmetric hydrocephalus diagnosed prenatally at our institution were reviewed. Postnatal outcome was obtained from maternal, neonatal, and pediatric records. Fourteen fetuses at 17.3 to 38.9 weeks' gestational age on prenatal sonography had a maximum ventricular measurement of 10.2 to 48.8 mm, with the degree of asymmetry ranging from 2.2 to 27.3 mm. Thirteen of 14 had a normal-sized contralateral ventricle. Other fetal anomalies identified at sonography included Dandy-Walker malformation, intraventricular hemorrhage, porencephalic cyst, hydronephrosis, pleural effusion, and mild dilatation of a renal pelvis. Eleven fetuses had follow-up prenatal sonography. Among these, ventricular dilatation resolved in 5, remained the same in 3, increased in 2, and decreased in 1. Postnatal outcome was normal in 6 cases (43%) and abnormal in 8 (57%), including 2 cases of in utero intracranial hemorrhage, 2 with congenital syndromes, 1 with an imperforate foramen of Monro, 1 with tuberous sclerosis, 1 with developmental delays, and 1 with cerebral palsy. Asymmetric unilateral hydrocephalus appears to represent an entity different from bilateral hydrocephalus in that there is less risk of perinatal death, there are fewer associated anomalies, and the overall prognosis is better. Outcome may be normal, but fetuses with increasing unilateral ventriculomegaly and cases associated with other brain abnormalities tend to have a poor neurologic outcome.

Prenatal ultrasonography and the diagnosis of fetal cleft lip.

OBJECTIVE: To determine the efficacy of obstetric ultrasonography in the detection of fetal cleft lip. METHODS: The study population included all women who had a fetal anatomic survey with adequate visualization of the face and who gave birth at Brigham and Women's Hospital between January 1, 1990, and January 31, 2000. All neonates born with cleft lip were identified from the Brigham and Women's Active Malformation Surveillance Program. Confirmation of the anatomic defect was obtained from the pediatric record or from the pathologic report if the pregnancy was terminated or ended in miscarriage. Cases of isolated cleft palate were excluded. An ultrasonography database was used to identify all cases of cleft lip diagnosed before delivery. Maternal information regarding the pregnancy was abstracted from the medical record. Statistical significance was determined using the chi2 statistic for categorical variables and the t test for continuous variables. RESULTS: A total of 56 confirmed cases of cleft lip were identified in the study population. Overall, 73% of the cases (41 of 56) were identified antenatally. Additional fetal anomalies were present in 54% of the cases (30 of 56). A comparison between those cases that were detected and those in which the diagnosis was missed showed that there was a significantly lower detection rate if the ultrasonography was performed before 20 weeks (12 [57%] of 21 versus 29 [83%] of 35; P = .035). There was no difference between the 2 groups in terms of maternal age or weight. Maternal parity, prior maternal abdominal surgery, the presence of a multiple gestation, or coexisting fetal anomalies did not significantly affect the detection rate. There was no difference in detection rate in the first half of the study period (1990-1995; 23 [72%] of 32) compared with the second half (1996-2000; 18 [76%] of 24; P = .79). CONCLUSIONS: In this cohort of women, the rate of detection of fetal cleft lip was significantly lower when the anatomic survey was performed before 20 weeks' gestation. This difference could not be accounted for by such variables as prior maternal abdominal surgery, coexisting fetal anomalies, or improvements in ultrasonographic detection with time. We recommend that the anatomic survey for fetuses at high risk for this condition be performed after 20 weeks' gestation.

Sonographic appearance of first trimester complete hydatidiform moles.

OBJECTIVE: Complete hydatidiform moles are now being diagnosed earlier in gestation, thus the clinical presentation and pathologic findings of complete molar pregnancy have changed. We studied the sonographic appearance of first trimester moles and the ability of ultrasound to detect them. METHODS: We reviewed the sonographic interpretation and sonograms, when available, from all patients with first trimester complete moles diagnosed at our institution from January 1988 to March 1996. RESULTS: Of the 24 patients in our study, the mean gestational age at time of the sonogram was 8.7 +/- 2.0 weeks (mean +/- SD) with a range of 5.7-12.3 weeks. The initial sonographic interpretation was a complete mole in 17 (71%) cases, partial mole versus failed pregnancy in two (8%), and failed pregnancy in five (21%) cases. Of the 22 patients with sonograms available for review, interpretation on review of the images was a complete mole in 18 (82%) cases, partial mole versus failed pregnancy in one (5%), and failed pregnancy in three (14%) cases. The typical sonographic appearance of a first trimester complete mole was a complex, echogenic, intra-uterine mass containing many small cystic spaces. CONCLUSION: The majority of first trimester complete moles demonstrate a typical ultrasound appearance such that the diagnosis can be made with ultrasound in most cases.

Usefulness of ultrasonography in the management of nodular thyroid disease.

BACKGROUND: Fine-needle aspiration biopsy is the standard diagnostic test for evaluating possible malignancy in a thyroid nodule. OBJECTIVE: To evaluate the role of routine ultrasonography in the management of nodular thyroid disease. DESIGN: Retrospective chart review. SETTING: Multidisciplinary thyroid nodule clinic (endocrinology and radiology). PATIENTS: Patients with suspected nodular thyroid disease or suspected recurrent thyroid cancer referred between October 1995 and March 1997. All patients had thyroid ultrasonography and ultrasonography-guided fine-needle aspiration biopsy of nodules at least 1 cm in maximum diameter. MEASUREMENTS: Medical records, ultrasonography findings, cytology reports, and histologic reports were reviewed. Ultrasonography findings were compared with the referring physician's findings on physical examination. RESULTS: 223 patients were seen in the clinic. A total of 209 fine-needle aspiration biopsies were performed on 156 patients. Among 50 of 114 patients referred for a solitary nodule, ultrasonography detected additional nonpalpable nodules at least 1 cm in diameter in 27 and determined that no nodules required aspiration in 23. Of 59 patients referred for a diffuse goiter or a multinodular gland, ultrasonography detected discrete nodules at least 1 cm in diameter that required aspiration in 39 and determined that aspiration was unnecessary in 20. CONCLUSIONS: Ultrasonography altered the clinical management for 63% of the patients (109 of 173) referred to the thyroid nodule clinic after abnormal results on thyroid physical examination.

US evaluation of the uterus in patients with postmenopausal bleeding: A positive effect on diagnostic decision making.

PURPOSE: To assess the accuracy of hysterosonography (HSG) and its role in diagnostic confidence and therapeutic clinical decision making among referring physicians caring for patients with postmenopausal bleeding (PMB). MATERIALS AND METHODS: One hundred twenty-three patients with PMB underwent transvaginal ultrasonography (US) and HSG. They were examined for cancer, polyp, leiomyoma, and hyperplasia. Physicians assessed the effect of the studies on diagnostic confidence and care, including biopsy, dilation and curettage, hysteroscopy, hormone manipulation, and/or patient reassurance. Abnormality was proved with histopathologic evaluation, and normality, with 6-month follow-up. RESULTS: In 10 patients, HSG was unsuccessful, and in 15, follow-up was incomplete; this left 98 patients. Endometrial polyps were seen in 46 (47%) patients; leiomyoma, in 11 (11%); cancer, in four (4%); hyperplasia, in eight (8%); and normal findings, in 29 (30%). Our calculations yielded a sensitivity of 98% and a specificity of 88%. In 86 (88%) patients, US added certainty to the diagnosis; in 78 (80%), it resulted in a change in patient treatment. CONCLUSION: HSG and transvaginal US in patients with PMB improves diagnostic accuracy, clinical decision making, and the clinician's diagnostic certainty. In patients with benign causes of PMB, the absence of abnormality at HSG and a normal endometrial biopsy result may eliminate the need for further studies.

Outcome of pregnancies with rapid embryonic heart rates in the early first trimester.

OBJECTIVE: We conducted a study to determine the upper limits of normal embryonic heart rate at or before 7.0 weeks' gestational age and to assess outcome of pregnancies in which the early embryonic heart rate is rapid. SUBJECTS AND METHODS: We recorded embryonic heart rates in 2817 sonograms at or before 7.0 weeks' gestation performed between January 1993 and June 1998. The upper limit of normal heart rate in two gestational age ranges (before 6.3 weeks and 6.3-7.0 weeks) was computed as the average of two values: mean heart rate + 1.96 standard deviations and the rate above which 2.5% of embryos in our population were measured. Pregnancy outcome in cases with rapid embryonic heart rates was compared with pregnancy outcome in a control group with normal rates. RESULTS: The upper limit of normal heart rate was 134 beats per minute before 6.3 weeks' gestation and 154 beats per minute at 6.3-7.0 weeks' gestation. Forty-one embryos had rapid early heart rates and known first-trimester outcome, of which 37 (90.2%) were alive at the end of the first trimester. Pregnancy outcome was available in 33 of the 37 first-trimester survivors (four were lost to follow-up before delivery), and 30 of these 33 (90.9%) were healthy neonates. These short- and long-term outcomes were not significantly different from those of the control group of embryos with normal early heart rates (p > 0.20, Fisher's exact test). CONCLUSION: A rapid early embryonic heart rate is one that is at least 135 beats per minute before 6.3 weeks or at least 155 beats per minute at 6.3-7.0 weeks. Pregnancies in which the embryo has a rapid early heart rate have a good prognosis, with a high likelihood of normal outcome.

Long-term prognosis of pregnancies complicated by slow embryonic heart rates in the early first trimester.

Slow embryonic heart rates at gestational age 7 weeks or less are associated with high risk of first trimester death. Our goal was to determine the prognosis for those embryos with slow early heart rates who survive the first trimester. We prospectively recorded embryonic heart rates for all obstetrical sonograms obtained on singleton pregnancies at or before 7.0 weeks' gestation since 1993. We collected information about pregnancy outcome, including date of live birth or in utero death and presence and nature of congenital anomalies. First trimester survival rate was 61.6% among 531 embryos with slow early heart rates (< 100 bpm at < or = 6.2 weeks, < 120 bpm at 6.3 to 7.0 weeks), lower than the survival rate of 91.5% among 1501 embryos with normal heart rates (p < 10(-8), Fisher's exact test). Among 299 pregnancies in which the early heart rate was slow and the fetus was still alive at the end of the first trimester, 277 (92.6%) resulted in liveborn infants without congenital anomalies, similar to the frequency of 95.1% in cases with normal early heart rates (p > 0.10, Fisher's exact test). Structural and chromosomal anomalies, however, occurred more than twice as frequently in cases with slow early heart rates: 5.4% (16 of 299) of the first trimester survivors with slow early heart rates proved to have anomalies, as compared to 2.4% (31 of 1281) of cases with normal early heart rates (p < 0.05, Fisher's exact test). In conclusion, a pregnancy in which the embryo has a slow heart rate at or before 7.0 weeks' gestation and which continues beyond the first trimester has a high likelihood (> 90%) of resulting in a liveborn neonate without congenital anomalies. Embryos with slow early heart rates do, however, have a greater risk of having anomalies than embryos with normal early heart rates.

Frequency and nature of structural anomalies in fetuses with single umbilical arteries.

Published studies differ concerning the rate of anomalies occurring in the presence of a single umbilical artery and the significance of the single umbilical artery as an isolated sonographic finding. We assessed the frequency, nature, and sonographic detection of structural anomalies in fetuses with a single umbilical artery. We identified all cases in which prenatal sonography diagnosed a single umbilical artery. Cases were excluded if postnatal physical or pathologic examination demonstrated a three-vessel cord, yielding a study population of 167 cases. For each case, we recorded the gestational age at diagnosis of single umbilical artery and the findings of the sonographic fetal anatomic survey. We recorded postnatal clinical and pathologic information when available. Gestational age at time of diagnosis ranged from 16.8 to 41.1 weeks (mean, 29.2 +/- 6.5 weeks). Twenty of the 167 fetuses (12%) were twins, and the remainder were singletons. Among 118 cases with postnatal information, 37 (31%) had structural abnormalities, often involving multiple organs. The most common organ systems involved were the heart (19 cases) and the gastrointestinal (14 cases) and central nervous systems (nine cases). Five of the anomalous fetuses had abnormal karyotypes. The sonographic survey was abnormal in 31 of the 37 anomalous fetuses (84%). Among 85 cases with apparently isolated single umbilical artery at sonography and known fetal outcome, six (7%) proved to be anomalous at birth. We had two sonographic false-positive results (mild hydronephrosis, suspected skeletal dysplasia). In summary, approximately one third of fetuses with single umbilical artery have structural anomalies, most often cardiac. Even when the single umbilical artery is an apparently isolated sonographic finding, the likelihood that the neonate will prove to have structural anomalies is considerable (7% in our series).