Nuchal Translucency Quality Review (NTQR) program: first one and half million results.

OBJECTIVE: To evaluate the performance of first-trimester nuchal translucency (NT) measurement by providers (physician-sonologists and sonographers) within the Nuchal Translucency Quality Review (NTQR) program. METHODS: After training and credentialing providers, the NTQR monitored performance of NT measurement by the extent to which an individual's median multiple of the normal median (MoM) for crown-rump length (CRL) was within the range 0.9-1.1 MoM of a published normal median curve. The SD of log10 MoM and regression slope of NT on CRL were also evaluated. We report the distribution between providers of these performance indicators and evaluate potential sources of variation. RESULTS: Among the first 1.5 million scans in the NTQR program, performed between 2005 and 2011, there were 1 485 944 with CRL in the range 41-84 mm, from 4710 providers at 2150 ultrasound units. Among the 3463 providers with at least 30 scans in total, the median of the providers' median NT-MoMs was 0.913. Only 1901 (55%) had a median NT-MoM within the expected range; there were 89 above 1.1 MoM, 1046 at 0.8-0.9 MoM, 344 at 0.7-0.8 MoM and 83 below 0.7 MoM. There was a small increase in the median NT-MoM according to providers' length of time in the NTQR program and number of scans entered annually. On average, physician-sonologists had a higher median NT-MoM than did sonographers, as did those already credentialed before joining the program. The median provider SD was 0.093 and the median slope was 13.5%. SD correlated negatively with the median NT-MoM (r = -0.34) and positively with the slope (r = 0.22). CONCLUSION: Even with extensive training, credentialing and monitoring, there remains considerable variability between NT providers. There was a general tendency towards under-measurement of NT compared with expected values, although more experienced providers had performance closer to that expected.

Systematic review of sonographic findings of placental mesenchymal dysplasia and subsequent pregnancy outcome.

OBJECTIVE: To describe the sonographic features and pregnancy outcomes of placental mesenchymal dysplasia (PMD), an entity often misdiagnosed as molar pregnancy. METHODS: We reviewed PMD cases from our institution and performed a systematic review of the existing literature. Inclusion criteria for the review were diagnosis of PMD as defined by placental pathology, description of placental morphology on antenatal ultrasound and reporting of pregnancy outcomes. RESULTS: We found three cases of PMD at our institution. Patient 1 had elevated human chorionic gonadotropin (hCG) and an enlarged, hydropic placenta at 13 weeks, suggestive of a molar pregnancy. Patient 2 also had elevated hCG with large, vascular placental lakes on ultrasound suggesting placenta accreta or molar pregnancy. Case 3 involved placentomegaly and fetal anomalies suggestive of Beckwith-Wiedemann syndrome. From the literature review, 61 cases met the inclusion criteria. The most common sonographic features included enlarged (50%) and cystic (80%) placenta with dilated chorionic vessels. Biochemical aneuploidy screening abnormalities were relatively common as were fetal anomalies, Beckwith-Wiedemann syndrome and other genetic abnormalities. Pregnancy complications included intrauterine growth restriction (IUGR; 33%), intrauterine fetal death (IUFD; 13%), and preterm labor (33%). Pregnancies without fetal anomalies, IUGR, IUFD or preterm labor had normal neonatal outcomes despite PMD (9%). CONCLUSIONS: The differential diagnosis of PMD includes molar pregnancy and other placental vascular anomalies. PMD is associated with adverse pregnancy outcome, so heightened surveillance with genetic evaluation, serial growth scans and third-trimester assessment of wellbeing should be considered. PMD must be differentiated from gestational trophoblastic disease because management and outcomes differ.

Evaluating the cost-effectiveness of prenatal surgery for myelomeningocele: a decision analysis.

OBJECTIVE: To determine whether prenatal myelomeningocele repair is a cost-effective strategy compared to postnatal repair. METHODS: Decision-analysis modeling was used to calculate the cumulative costs, effects and incremental cost-effectiveness ratio of prenatal myelomeningocele repair compared with postnatal repair in singleton gestations with a normal karyotype that were identified with myelomeningocele between T1 and S1. The model accounted for costs and quality-adjusted life years (QALYs) in three populations: (1) myelomeningocele patients; (2) mothers carrying myelomeningocele patients; and (3) possible future siblings of these patients. Sensitivity analysis was performed using one-way, two-way and Monte Carlo simulations. RESULTS: Prenatal myelomeningocele repair saves $ 2 066 778 per 100 cases repaired. Additionally, prenatal surgery results in 98 QALYs gained per 100 repairs with 42 fewer neonates requiring shunts and 21 fewer neonates requiring long-term medical care per 100 repairs. However, these benefits are coupled to 26 additional cases of uterine rupture or dehiscence and one additional case of neurologic deficits in future offspring per 100 repairs. Results were robust in sensitivity analysis. CONCLUSION: Prenatal myelomeningocele repair is cost effective and frequently cost saving compared with postnatal myelomeningocele repair despite the increased likelihood of maternal and future pregnancy complications associated with prenatal surgery.

Universal cervical-length screening to prevent preterm birth: a cost-effectiveness analysis.

OBJECTIVE: To determine whether routine measurement of second-trimester transvaginal cervical length by ultrasound in low-risk singleton pregnancies is a cost-effective strategy. METHODS: We developed a decision analysis model to compare the cost-effectiveness of two strategies for identifying pregnancies at risk for preterm birth: (1) no routine cervical length screening and (2) a single routine transvaginal cervical length measurement at 18-24 weeks' gestation. In our model, women identified as being at increased risk (cervical length < 1.5 cm) for preterm birth would be offered daily vaginal progesterone supplementation. We assumed that vaginal progesterone reduces preterm birth at < 34 weeks' gestation by 45%. We also assumed that a decreased cervical length could result in additional costs (ultrasound scans, inpatient admission) without significantly improved neonatal outcomes. The main outcome measure was incremental cost-effectiveness ratio. RESULTS: Our model predicts that routine cervical-length screening is a dominant strategy when compared to routine care. For every 100,000 women screened, $12,119,947 can be potentially saved (in 2010 US dollars) and 423.9 quality-adjusted life-years could be gained. Additionally, we estimate that 22 cases of neonatal death or long-term neurologic deficits could be prevented per 100,000 women screened. Screening remained cost-effective but was no longer the dominant strategy when cervical-length ultrasound measurement costs exceeded $187 or when vaginal progesterone reduced delivery risk at < 34 weeks by less than 20%. CONCLUSION: In low-risk pregnancies, universal transvaginal cervical length ultrasound screening appears to be a cost-effective strategy under a wide range of clinical circumstances (varied preterm birth rates, predictive values of a shortened cervix and costs).

Assessment of the fetal thymus by two- and three-dimensional ultrasound during normal human gestation and in fetuses with congenital heart defects.

OBJECTIVES: Our objectives were to compare the size and volume of the developing fetal thymus obtained by two-dimensional ultrasound (2D-US) and three-dimensional ultrasound (3D-US), develop normative data for thymus volume (TV), and investigate TV in fetuses with congenital heart disease (CHD) and normal twin gestations. METHODS: We studied 321 fetuses (gestational age (GA): 17-39 weeks) including 238 normal singletons, 64 normal twins and 19 singleton fetuses with CHD. We used 2D-US to assess fetal thymus maximum transverse diameter (MTD), maximum transverse area (MTA), anteroposterior diameter (APD) and superoinferior diameter (SID). TV was obtained by 3D-US using virtual organ computer-aided analysis. Measurements were adjusted for estimated fetal weight where appropriate. Linear regression analysis, general linear models and Fisher's Z-transformation were used where appropriate. A nomogram of fetal TV based on singleton gestations was produced according to previously published methods. RESULTS: Ultrasound assessment of the fetal thymus was possible in 95.3% (306/321) of cases. Both 3D-US and 2D-US measurements were significantly correlated with GA (TV r = 0.989; MTA r = 0.918; MTD r = 0.884; APD r = 0.849; and SID r = 0.816; all P < 0.05). After Fisher's Z-transformation, the correlation between the TV and GA was significantly stronger than that between any individual 2D-US measurement and GA (P < 0.05). Normal twin fetuses had TVs similar to those of singletons adjusted for estimated fetal weight and GA (P = 0.85). TV adjusted for estimated fetal weight and GA was significantly lower in fetuses with CHD than in normal singletons (P < 0.05). CONCLUSION: 2D-US and 3D-US are useful tools for evaluation of the size and volume of the human fetal thymus through gestation. Fetal TV by 3D-US seems to reflect normal development of the thymus in utero better than do 2D-US measurements. Lower TV should be expected in association with CHDs.

Congenital heart defects in twin gestations.

As ultrasound technology advances, diagnosis of fetal malformations, particularly congenital heart defects (CHD) is becoming standard practice. Currently, a key element of obstetrical care is the use of ultrasound to diagnose chorionicity in multiple gestations. Given the difference in incidence and types of complications between dichorionic and monochorionic pregnancies, early diagnosis of chorionicity is critical to determine the type of care and counseling a patient receives throughout the pregnancy. Early diagnosis of chorionicity allows investigators to more accurately determine the risk of CHD in monochorionic pregnancies. It has been long known that twin gestations incur a higher risk of congenital malformations, including CHD. However, it was not until recently that the incidence could be determined according to chorionicity. Previous studies looking at risk of malformations including CHD used the like-sex technique as a proxy for chorionicity, thereby overestimating the prevalence of monochorionic twins because roughly two-thirds of all twin gestations (including dichorionic) are the same sex. The rate of multiple gestations is increasing in the developed world. Assisted reproductive technology (ART) is partly responsible for the increased incidence of multiples. While many of the ART conceived pregnancies are dichorionic multiples, there is evidence that ART increases the risk of monochorionic multiple gestations. Presently, it is not technically feasible, nor practical, to screen all pregnancies with fetal echocardiography. Thus, many perinatal ultrasound centers screen women for risk factors that place them at higher risk for having a fetus with CHD. This higher risk' group then receives a fetal echocardiogram. The available literature regarding risk of CHD in monochorionic multiple gestations strongly points to a significant increase over the general population risk of 0.5-0.8%. Fetal echocardiography is technically feasible in twin pregnancies and increasingly available. Monochorionic multiple gestations should be screened with fetal echocardiography.

Indications for fetal echocardiography.

Congenital heart disease is one of the most common congenital malformations diagnosed in liveborns. As more women undergo prenatal diagnosis, the need for screening fetal echocadiography increases. The fetal, maternal, and familial indications for fetal echocadiography are outlined in order to improve the identification of women in greatest need for this screening modality.

Delivery at 34 weeks is more costly than at 35 weeks in pregnancies with premature rupture of membranes.

OBJECTIVE: To assess the relative risks and costs of delivery at 34 vs. 35 weeks with preterm premature rupture of membranes (PROM). STUDY DESIGN: Retrospective study of singleton gestations with preterm PROM over a 5-year period. Patients who delivered at 34 vs. 35 weeks were compared. RESULTS: Sixty-five patients were identified in each group. There were no significant differences in maternal demographics or complications. Direct costs of mother-infant pairs at 34 weeks were significantly higher (dollars 6687 +/- 4273 vs. dollars 4089 +/- 3037, p = 0.0001). Newborn intensive care unit stay was significantly longer for infants born at 34 weeks (8.4 +/- 7.1 vs. 3.5 +/- 4.6 days, p < 0.0001). CONCLUSIONS: There was a significant increase in neonatal interventions, neonatal length of stay and cost for infants delivered at 34 vs. 35 weeks. Prospective data are necessary to evaluate the actual maternal and neonatal morbidity incurred by delay of delivery.

Pulmonary hypoplasia and persistent pulmonary hypertension in the newborn with homozygous alpha-thalassemia: a case report and review of the literature.

The survival of infants with homozygous alpha-thalassemia, once considered a lethal diagnosis, is now possible through in utero and postnatal diagnostic and therapeutic interventions. We report the survival of a newborn with homozygous alpha-thalassemia complicated by pulmonary hypoplasia and persistent pulmonary hypertension, an association not previously reported.

Can risk factor assessment replace universal screening for gonorrhea and Chlamydia in the third trimester?

The objective of this study is to determine whether risk factor (RF) screening can be used instead of routine third-trimester testing for gonorrhea and chlamydia in a clinic setting. We performed prospective analysis of women entering prenatal care over a 10-month period. Patients included received combined gonorrhea and chlamydia screening by DNA probe at the first prenatal visit and in the third trimester. RF examined included age <20, marital status, history of sexually transmitted disease (STD) or hepatitis, drug use and gestational age at entry into prenatal care. Only women with negative initial screens were included in univariate and multivariate analyses. Five hundred forty-two women fulfilled study criteria. Sixty percent had 1 RF; 35% had a history of STD. Third-trimester screens were positive in 4.1%. The absence of RF had a negative predictive value of 99.1%. The sensitivity and specificity of RF screening was 90.9 and 40.7%, respectively (p = 0.003). The model of best fit was obtained using any positive RF and teen as independent variables (relative risk 6.9, 95% confidence interval 1.6-29.6, p = 0.01). In an urban clinic population, comprehensive RF screening is effective in predicting women at low risk for STD in the third trimester after an initial negative test.

Changes in fetal hemodynamics with ritodrine tocolysis.

OBJECTIVE: To evaluate the effect of ritodrine on the fetal cardiovascular system. METHODS: Cardiac and extracardiac Doppler waveforms were recorded in 12 fetuses prior to and during ritodrine therapy used for preterm labor. Maternal and fetal heart rates, the Doppler pulsatility indices of the umbilical artery, middle cerebral artery, descending thoracic aorta and renal artery, and time velocity integrals of the atrioventricular valves and the ductus arteriosus, were measured. RESULTS: Ritodrine infusion caused an increase in maternal and fetal heart rates, the left cardiac output as measured by the product of time velocity integral and heart rate, and the pulsatility index of the middle cerebral artery, and a decrease in the pulsatility index of the umbilical artery. CONCLUSIONS: Ritodrine infusion may alter placental and cerebral blood flow and may have a selective effect on the left side of the heart.

Ratio of nuchal thickness to humerus length for Down syndrome detection.

OBJECTIVE: Ultrasonographic biometry markers are now being used clinically to adjust Down syndrome risk. The limitations are that the definitions of "abnormal" measurements used are arbitrary, thus reducing screening performance, and also that patient-specific Down syndrome risks cannot be calculated. We report a new ultrasonographic algorithm that is sensitive for Down syndrome detection and that estimates individual risk. STUDY DESIGN: Overall in fetal populations with Down syndrome the humerus length is decreased, whereas the nuchal thickness is increased relative to that of a normal population. The nuchal thickness/humerus length ratio therefore shows an even greater increase and magnifies the separation between Down syndrome and healthy groups. Prospective data were collected in midtrimester amniocentesis cases. A regression equation for the median nuchal thickness/humerus length ratio based on biparietal partial diameter was generated. The Down syndrome likelihood ratio, or the odds on the basis of the nuchal thickness/humerus length ratio (multiples of the median), was multiplied by the age-related risk to give the posterior Down syndrome risk. Charts for rapid estimation of individual Down syndrome risk on the basis of maternal age and the nuchal thickness/humerus length ratio were constructed. RESULTS: There were 94 cases of Down syndrome and 4700 cases in which the karyotype was normal. The mean (+/-SD) gestational age of the study population was 16.1 +/- 1.6 weeks. Thirty-three fetuses with Down syndrome and 68 karyotypically normal fetuses had gross anomalies. The equation for the expected median nuchal thickness/humerus length ratio was as follows: 10e(1.7163 - 0.0292) x BPD + 0.0003 x BPD2, where BPD is the biparietal diameter. In the overall study population the nuchal thickness/humerus length ratio and maternal age had a 79.8% detection rate at a 22.1% false-positive rate, compared with maternal age plus humerus length (sensitivity, 55.1%) or maternal age plus nuchal thickness (sensitivity, 66.7%) at the same false-positive rate. For women > or =35 years old the values were 80% and 22.0%, respectively. CONCLUSIONS: We report an ultrasonographic biometry algorithm that, in combination with maternal age, detects 79.6% of Down syndrome cases in a high-risk group. Individual Down syndrome risk can be quickly calculated at the bedside and made available to women who desire this information before making a decision on amniocentesis. On the basis of published standards, ultrasonographic biometry as described would be a cost-effective alternative to amniocentesis in this high-risk group.

Prenatal diagnosis of congenital heart disease affects preoperative acidosis in the newborn patient.

OBJECTIVES: Congenital heart disease is the leading cause of death in the first year after birth. Prenatal diagnosis of the disease can optimize the preoperative condition of the patient and may help in the prevention of acidosis. In this retrospective study we compared the occurrence of metabolic acidosis in patients with and without prenatal diagnosis of a congenital heart disease. METHODS: Data of 408 patients who needed an operation for congenital heart disease within 31 days of life were analyzed retrospectively. Arterial blood gases at fixed time intervals and worst blood gas of 81 patients with and 327 patients without a prenatal diagnosis were compared, categorizing the patients on ductus dependency, anticipated univentricular or biventricular repair, and left-sided, right-sided, or no heart obstruction. RESULTS: In the overall group significant differences in lowest pH, lowest base excess, and highest lactate level were found, with metabolic acidosis more common among the patients with a postnatal diagnosis. In the group of patients with ductus-dependent congenital heart disease, the difference between patients receiving a prenatal and those receiving a postnatal diagnosis was more significant than in the group with non-ductus-dependent lesions. Analyzing patients with right-sided, left-sided, and no obstruction separately, significant differences were found in the group with left-sided heart obstruction for lowest pH and base excess and in the group with right-sided heart obstruction for lowest base excess. CONCLUSIONS: Prenatal diagnosis of congenital heart disease minimizes metabolic acidosis in patients with congenital heart disease and may be associated with improved long-term outcome and prevention of cerebral damage among this fragile group of patients, although no significant effect on direct surgical outcome was encountered.