The utilization of circulating cell-free fetal DNA testing and decrease in invasive diagnostic procedures: an institutional experience.

OBJECTIVE: To characterize the patient population utilizing circulating cell-free fetal DNA (ccffDNA) testing at a large academic center and evaluate trends in the performance of invasive diagnostic procedures. STUDY DESIGN: A retrospective cohort study of all patients who underwent cell-free DNA testing from May to December 2012 was performed. RESULT: During the study period, 206 patients had cell-free DNA testing. Of those, 75% (155/206) were of ages ⩾ 35 years. Of those undergoing ccffDNA testing, 41% had positive aneuploidy screening and 38% had abnormal ultrasound findings. Only 7% of the patients with negative ccffDNA testing opted for an invasive diagnostic procedure compared with 60% with positive testing (P<0.01). The rate of invasive procedures decreased from 5.9% of all visits to the center during a similar 8-month period in 2010 to 4.1% of all visits during the study period (P<0.01). CONCLUSION: Our data suggest that ccffDNA testing leads to reduced uptake of invasive procedures.

Reducing the cost of detection of congenital heart disease in fetuses of women with pregestational diabetes mellitus.

OBJECTIVE: To provide a cost minimization analysis to support a paradigm shift in the use of comprehensive ultrasound and echocardiography in the prenatal diagnosis of congenital heart disease (CHD) in fetuses of women with diabetes mellitus (DM). METHODS: In this retrospective cohort study, the diabetic clinic service database of the University of California San Diego was searched from January 2001 to June 2004 for pregnant women with Type I or II DM and HbA1c >6.3%. Subjects underwent comprehensive ultrasound examination (with four-chamber views and outflow tracts) and fetal echocardiography according to a standard protocol. Newborns were examined for cardiac defects and underwent postnatal echocardiography as indicated. The cost of screening was evaluated. RESULTS: Of 115 neonates and two terminations of pregnancy there were 20 (17%) cases of CHD. Six of these CHD were major and all six were detected prenatally by both ultrasound and echocardiography. Three additional clinically insignificant cases of CHD were identified by fetal echocardiography. Eleven cases of CHD were identified by postnatal echocardiography only, all of which were clinically insignificant lesions. The prenatal detection rate of major CHD was 100% (6/6) for both ultrasound and echocardiography. The sensitivites of ultrasound (30% (95% CI, 13-54%)) and echocardiography (45% (95% CI, 24-68%)) were similar (P = 0.32). A cost minimization analysis was done using the published Medicaid (California) system's relative value unit and conversion factors. Accordingly, our current protocol costs $6503.43 per case of major CHD detected. If echocardiography had been performed only as indicated and postnatal echocardiography had been performed on all neonates, the cost would have been $7056.83 per case of major CHD detected. Alternatively, combined targeted ultrasound with indicated prenatal and postnatal echocardiography would have been associated with a cost of $4996.05 per case of major CHD detected. CONCLUSION: Detection of major CHD was excellent with both comprehensive prenatal ultrasound and echocardiography. Echocardiography added little to the prenatal diagnosis of CHD if the comprehensive ultrasound examination was normal. The highest cost-benefit ratio and most efficacious protocol for screening based on our data would be comprehensive ultrasound with prenatal and postnatal echocardiography only as indicated. Further prospective studies are warranted.

Can prenatal ultrasound detect the effects of in-utero alcohol exposure? A pilot study.

OBJECTIVES: The aim of this pilot study was to explore possible ultrasound parameters for the early detection of alcohol-mediated fetal somatic and central nervous system (CNS) maldevelopment. Maternal alcohol ingestion during pregnancy may lead to fetal alcohol spectrum disorders (FASD), which encompass a broad range of structural abnormalities including growth impairment, specific craniofacial features and CNS abnormalities. Early detection of fetuses at risk of FASD would support earlier interventions. METHODS: We performed a longitudinal prospective pilot study from 2004 to 2006 at two sites in Ukraine. A sample of pregnant women who reported consuming moderate-to-heavy amounts of alcohol participated in a comprehensive maternal interview, and received ultrasound evaluation of fetal growth and specific fetal brain measurements during the second and third trimesters. These measurements were compared with those collected from a group of pregnant women who consumed little-to-no alcohol during pregnancy, and who were recruited and followed in the same manner. RESULTS: From 6745 screened women, 84 moderate-to-heavy alcohol users and 82 comparison women were identified and ultrasound examinations performed. After controlling for maternal smoking, alcohol-exposed fetuses had shorter mean femur length, caval-calvarial distance and frontothalamic measurements in the second trimester (P < 0.05), and alcohol-exposed fetuses also had shorter frontothalamic distance measurements in the third trimester relative to comparison fetuses (P < 0.05). In addition, after controlling for maternal smoking, both mean orbital diameter and biparietal diameter measurements were significantly smaller on average in the alcohol-exposed group in the third trimester relative to comparison fetuses (P < 0.05). CONCLUSIONS: Significant differences in selected somatic and brain measurements were noted between alcohol-exposed and comparison fetuses, suggesting these markers may be further explored for clinical utility in prenatal identification of affected children. Further study correlating these findings with alcohol-related physical features of the newborn and subsequent comparisons of neuro-developmental outcomes will help define potential uses of prenatal ultrasound for intervention and prevention of FASD.

Prenatal three-dimensional ultrasound: perception of sonographers, sonologists and undergraduate students.

OBJECTIVE: To assess the perception of non-pregnant sonographers, sonologists and undergraduate students on the use of three-dimensional (3D) ultrasound technology in fetal medicine. METHODS: This was a study of two groups of non-pregnant subjects. Group I included 520 (305 female, 215 male) medical professionals who completed a questionnaire after attending a lecture on 3D imaging. Factors such as gender, career and having children were analyzed with respect to the attendee's responses about use of 3D ultrasound for medical purposes and for reassurance. Group II included 137 (75 female, 60 male, two unknown) undergraduate students from bioengineering, psychology and physiology classes who completed a questionnaire after attending a brief presentation on two-dimensional and 3D fetal imaging. Factors such as gender and area of educational interest were analyzed with respect to the students' responses about the use of 3D ultrasound for medical purposes and for parental-fetal attachment. RESULTS: In Group I, 63% said that they would like to have a 3D ultrasound examination in the future, while 14% said that they would not. Common reasons given for wanting a 3D ultrasound exam in the future were for medical purposes (39%) or reassurance (18%). The main differences perceived between two-dimensional (2D) and 3D ultrasound were medical advantages (65%) and parental reassurance (28%). 62.4% of Group I thought 3D technology should be in wide use in obstetric ultrasound and 73.6% thought that 3D ultrasound would reassure parents carrying normal fetuses. Gender, age and career did not have a significant influence on perception of 3D ultrasound. In Group II, the majority (91%) said they could see a remarkable difference between 2D and 3D ultrasound. 83% responded that they would like to have a 3D ultrasound examination of their own baby in the future for the following reasons: 34% for the detailed picture, 31% for increased abnormality detection, 13% for reassurance or curiosity; 8% thought it would be unnecessary or a negative experience. Concerning parental-fetal attachment, 72% thought 3D ultrasound would have a positive effect. The majority of Group II (93%) thought 3D ultrasound would be valuable and 56% thought 3D ultrasound would assist in diagnosing fetal abnormalities. There was no significant relationship between gender, age or area of interest and the perception of 3D ultrasound. CONCLUSIONS: Responses by sonographers and physicians suggest that 3D ultrasound will have a role in the future for medical indications and in reassuring patients carrying normal fetuses. Our results also suggest that undergraduate students believe that 3D ultrasound will be a valuable technique in obstetrics and that it will have a positive effect on parental-fetal attachment.

Effects of ultrasound on maternal-fetal bonding: a comparison of two- and three-dimensional imaging.

OBJECTIVES: The purpose of this study was to evaluate the effect of two-dimensional (2DUS) compared to three-dimensional ultrasound (3DUS) imaging on the maternal-fetal bonding process. METHODS: Fifty mothers who had 2DUS and 50 who had 2DUS and 3DUS were included in the study. A postpartum survey by telephone interview was carried out to assess maternal-fetal bonding. Bonding was evaluated by analysis of extent of prenatal image sharing, maternal ability to form a mental picture of the baby and mother's comments about their ultrasound images. Data were analyzed using the independent t-test, Chi-square and Mann-Whitney U-tests. RESULTS: Mothers who received 3DUS showed their ultrasound images to more people (median, 27.5; interquartile range, 14.5-40.0) than mothers receiving 2DUS alone (median, 11.0; interquartile range, 5.0-25.5) (P < 0.001, Z = -3.539). Eighty-two percent of the subjects screened with 3DUS had a greater tendency to form a mental picture of the baby postexamination compared to 39% of the 2DUS subjects (P < 0.001, Z = -3.614). Mothers receiving a 3DUS study were more likely to receive comments on the similarities/differences of the neonate compared to those having 2DUS studies. Furthermore, 70% of the mothers receiving 3DUS felt they 'knew' the baby immediately after birth vs. 56% of the mothers receiving 2DUS (P = 0.009, Z = -2.613). Both 2DUS and 3DUS experiences were positive, however, the comments made by the mothers undergoing 3DUS (n = 18) were more exclamatory (amazed, wonderful, fabulous) than those undergoing 2DUS (n = 4). Patients having a 3DUS examination consistently scored higher than those having a 2DUS examination alone for all categories of maternal-fetal bonding. CONCLUSION: 3DUS appears to more positively influence the perceptions of mothers to their babies postbirth compared to 2DUS. Specifically, mothers who had 3DUS showed their ultrasound images to a greater number of people compared to mothers who had 2DUS alone and this may represent mother's social support system. 3DUS may have a greater impact on the maternal-fetal bonding process.

Erythrocyte and erythropoietin responses to hemorrhage in the immature and near term ovine fetus.

OBJECTIVE: Previous reports suggested that immature ovine fetuses have a greater erythropoietin response to hemorrhage than those near term. This study tested the hypothesis that immature ovine fetuses would expand their red cell mass more rapidly than near term fetuses after hemorrhage. STUDY DESIGN: Chronically catheterized immature ovine fetuses at 109.5 +/- 0.3 (mean +/- SE) days' gestation (term = 150 days) were studied over a 10-day period. They either underwent hemorrhage of 40% of their measured blood volume on day 3 or were in a time control group monitored without hemorrhage. Red cell mass, hematocrit, blood volume, plasma volume, and plasma erythropoietin concentrations were measured at 24- and 48-hour intervals. Responses in the immature fetuses were compared with responses in near term fetuses. RESULTS: In the control group red cell mass, hematocrit, blood, and plasma volumes increased significantly, whereas plasma erythropoietin concentration decreased significantly with advancing gestational age. In immature fetuses that underwent hemorrhage, the relative changes in red cell mass, hematocrit, and plasma erythropoietin concentration were not significantly different from those seen in the near term fetuses. The only significant posthemorrhage difference was that the increases in blood and plasma volumes were greater in the immature compared with the near term fetuses. CONCLUSION: Immature and mature fetuses have similar erythrocyte and erythropoietin responses to moderately severe hemorrhage. The larger blood and plasma volume responses in the immature fetuses are consistent with the concept that they have a greater extracellular fluid volume.

Detection of Jarcho-Levin syndrome at 12 weeks' gestation by nuchal translucency screening and three-dimensional ultrasound.

Jarcho-Levin syndrome (JLS) or spondylothoracic dysotosis causes early newborn death from respiratory insufficiency. Prenatal diagnosis is possible using fetal ultrasound, but requires a high level of suspicion and definitive diagnosis may be delayed well into the second trimester. We present a case in which a combination of three-dimensional ultrasound and measurement of nuchal translucency thickness allowed successful detection of recurrent JLS at 12 weeks' gestation.

Three-dimensional ultrasonography and assessment of the first-trimester fetus.

We used transvaginal three-dimensional ultrasonography to assess the first-trimester fetus and compared the findings with contemporaneous two-dimensional ultrasonographic studies. Multiplanar three-dimensional ultrasonography provided good visualization of fetal anatomy and allowed fetal measurement and assessment of nuchal translucency thickness. Three-dimensional ultrasonography required significantly less time to perform and to interpret than two-dimensional ultrasonography. Three-dimensional ultrasonography is an effective means of assessing the first-trimester fetus and offers potential advantages over two-dimensional ultrasonography.

Three-dimensional ultrasonographic imaging of the neonatal brain in high-risk neonates: preliminary study.

The aim of this investigation was to compare the utility of three-dimensional ultrasonography versus two-dimensional ultrasonography in imaging the neonatal brain. Thirty patients in the neonatal intensive care unit underwent two-dimensional and three-dimensional ultrasonography. The resultant two- and three-dimensional images recorded on film and three-dimensional volumes (reviewed on a workstation) were evaluated independently. Comparable numbers of normal and abnormal studies were diagnosed by each modality. Axial images were considered useful in approximately 50% of three-dimensional cases. Image quality, overall and in the far-field, was rated higher on two-dimensional images. Three-dimensional sonographic acquisition time in the neonatal intensive care unit (1.7 min+/-0.7 standard deviation) was significantly shorter than that for two-dimensional sonography (9.0+/-4.5 min). The total time for evaluation on the three-dimensional workstation (4.4+/-1.1 min) was significantly less than that for two-dimensional images on film (10.6+/-4.7 min). In conclusion, three-dimensional ultrasonography is a promising, diagnostically accurate, and efficient imaging tool for evaluation of the neonatal brain; however, visualization must improve before it can replace two-dimensional ultrasonography.

Artifacts and the visualization of fetal distal extremities using three-dimensional ultrasound.

OBJECTIVES: To demonstrate that acoustic shadowing in 3D US may give rise to artifacts simulating limb defects and provide a solution to eliminate its occurrence. METHODS: Twenty second trimester fetuses (gestational age 15-24 weeks) were scanned with three-dimensional ultrasound (3D US) using a sagittal acquisition plane. Fetal tibia/fibula and radius/ulna pairs were assessed for completeness of imaging. A further 20 fetuses (gestational age 20-26 weeks) were scanned in both axial and sagittal planes and the results compared to verify clear visualization of both bones. RESULTS: Shadowing from adjacent structures produced an apparent limb defect in 55% of the first 20 fetuses imaged only sagittally (18% of limb pairs). Acquiring data from more than one orientation avoided this artifact. CONCLUSIONS: The 3D US is subject to the same artifacts as two-dimensional (2D US) in terms of acoustic shadowing, although their presentation may be different. Awareness of this fact is essential for correct interpretation of 3D US studies. Three-dimensional scanning protocols should be modified to ensure that fetal structures are adequately visualized by acquiring volume data in more than one acquisition orientation.

Correction of hemorrhage-induced anemia with intra-amniotic iron in the ovine fetus.

OBJECTIVE: This study tested the hypothesis that intra-amniotic iron treatment would enhance fetal red blood cell production after an acute, severe fetal hemorrhage of 40% of estimated blood volume over 2 hours. STUDY DESIGN: Three groups of late-gestation ovine fetuses were studied for 10 days: (1) control fetuses (n = 8), (2) fetuses hemorrhaged on day 3 (n = 11), and (3) similarly hemorrhaged fetuses supplemented with a single bolus of 60 mg of iron injected intra-amniotically immediately after the hemorrhage (n = 7). Statistical analysis was by 3-factor analysis of variance. RESULTS: At 24 hours after hemorrhage, red blood cell mass increased 5% in the control group and was reduced equally in both hemorrhage groups by 32% below day 3 prehemorrhage values. At 7 days after hemorrhage, red blood cell mass increased 27.8% +/- 2.6% (SE) above day 3 baseline values in the control fetuses. In the nonsupplemented hemorrhaged fetuses, red blood cell mass was not different from prehemorrhage values after 7 days (+3.7% +/- 4.1%), whereas red blood cell mass increased by 29.9% +/- 6.1% above prehemorrhage values in the iron-supplemented hemorrhage group (P <.001). CONCLUSION: Intra-amniotic iron supplementation resulted in full restoration of red blood cell mass within 7 days after a large loss of blood in fetal sheep, whereas restoration failed without iron supplementation. Intra-amniotic iron treatment may be of therapeutic value in restoring red blood cell mass in human fetuses with certain types of anemia such as that resulting from fetal or fetomaternal hemorrhage.

Effects of maturation on cyclic GMP-dependent vasodilation in ovine basilar and carotid arteries.

The present experiments examine the effects of maturation on cyclic GMP (cGMP)-mediated vasodilation in 688 segments of common carotid (COM) and basilar (BAS) arteries taken from newborn (3- to 7-d-old) and nonpregnant adult sheep. The main finding is that maximum efficacy for relaxation decreased with maturation in both artery types for the nitric oxide releasing vasodilators S-nitroso-N-acetyl-penicillamine and nitroglycerin. These decreases could not be explained by changes in the -log ED50 concentrations for either vasodilator. Determination of the time course of cGMP responses to S-nitroso-N-acetyl-penicillamine or nitroglycerin at 10 microM revealed that the peak cGMP responses to these agents (range: 5.3 +/- 0.8 to 8.3 +/- 1.6 pmol/mg of protein) also did not vary significantly with age. However, cGMP attained peak values more rapidly in adult (COM: 50 s; BAS 30 s) than in newborn (COM: 60-80 s: BAS, 40-60 s) segments and returned to baseline more slowly in newborn than in adult segments, suggesting that maturation accelerates cGMP turnover. Correspondingly, baseline levels of cGMP were higher in newborn (COM: 1.0 +/- 0.1; BAS: 3.3 +/- 0.5 pmol/mg of protein) than in adult (COM: 0.3 +/- 0.1; BAS: 1.7 +/- 0.2 pmol/mg of protein) segments. Despite these differences in cGMP time course, rates of relaxation in response to S-nitroso-N-acetyl-penicillamine and nitroglycerin did not vary significantly with age, indicating that the temporal relation between cGMP and relaxation is different in newborn and adult arteries.(ABSTRACT TRUNCATED AT 250 WORDS)

Endothelium-derived relaxing factor and cyclic GMP-dependent vasorelaxation in human chorionic plate arteries.

Endothelium derived relaxing factor (EDRF), now widely believed to be nitric oxide (NO), may play an important part in the control of fetoplacental vascular tone. To further explore this role we have determined the relaxation responses to exogenous NO and examined the temporal relationship between intracellular concentrations of cyclic GMP and vascular tone in isolated ring segments of human chorionic plate arteries. We have also determined the dose relations for the contractile agonists serotonin and the thromboxane analog U46619. Lastly, we have explored the relaxation responses to a wide range of agents known to elicit EDRF release in other vascular beds. Chorionic plate arteries relaxed significantly to exogenous NO with concomitant increases in cyclic guanosine monophosphate over basal values. ED50s for serotonin and U46619 were 1.48 x 10(-6) M and 3.39 x 10(-8) M respectively. The ED50 for NO derived from S-nitroso-N-acetyl-penicillamine was 1.28 x 10(-6) M. Endothelium-intact segments of chorionic plate arteries pre-contracted with either serotonin or U46619 failed to relax significantly to acetylcholine, adenosine diphosphate, A23187, bradykinin, and histamine and only minimally to substance P. We suggest that EDRF is likely to be important in the control of placental vascular tone, but that it is not possible to demonstrate its action in an unperfused experimental system.

Pregnancy alters cerebrovascular adaptation to high-altitude hypoxia.

We have previously shown alterations in cerebrovascular composition, contractility, and endothelial function in normoxic pregnant (P) and chronically hypoxic nonpregnant (HNP) adult sheep compared with nonpregnant normoxic controls (NP). This study focuses on a fourth group, pregnant sheep exposed to chronic high-altitude hypoxia (HP) (110 days at 3,820 m). The combined challenges of pregnancy and high-altitude hypoxia resulted in significant alterations in cerebrovascular function that were not simply the summation of the responses seen in the P and HNP animals. Compared with NP, HP arteries had increased protein content and increased intracranial arterial wall thickness. Both P and HP arteries showed increased contractility, while HNP artery maximum tensions were depressed. Endothelial function was depressed in the P common carotid and was enhanced in all HNP arteries. In contrast, an increased endothelial response was shown only in the HP common carotid. Thus, for contractility, the effects of pregnancy predominated in the HP arteries. For endothelial function, hypoxia effects were dominant in the common carotid but not in the intracranial arteries. Clearly, cerebrovascular characteristics are dynamic in nature, with artery-specific responses to both pregnancy and hypoxia.

Cerebrovascular adaptations to high-altitude hypoxemia in fetal and adult sheep.

In the fetus and infant, high-altitude hypoxemia is associated with increased cerebrovascular morbidity. To test the hypothesis that this increased morbidity involves changes in cerebrovascular endothelial and smooth muscle function, we examined middle cerebral, posterior communicating, basilar, and common carotid arteries obtained from 23 normoxic fetuses, 19 hypoxemic fetuses maintained at high altitude (3,820 m) from 30 days gestation to near term (approximately 143 days), 55 normoxic non-pregnant adults, and 24 hypoxemic nonpregnant adults maintained at the same altitude and duration as the hypoxemic fetuses. Long-term hypoxemia was associated with several significant changes in both fetal and adult arteries, including a generalized increase in base-soluble protein (5-50%), a depression of the maximum potassium-induced tensions (16-49%), and a depression of the relaxation responses to S-nitroso-N-acetylpenicillamine (1-11%), which releases nitric oxide into solution upon hydration. Altitude acclimatization significantly enhanced amine-to-potassium ratios (the ratio of tension produced by 10 microM serotonin with 20 microM histamine to that produced by 122 mM potassium) only in adult cerebral arteries (51-87%) and significantly depressed potassium-induced stresses (up to 41%) and serotonin/histamine-induced tensions (20-37%) only in fetuses. Endothelium-dependent relaxations to A23187 were significantly depressed in hypoxemic fetuses (4-11%) but were significantly enhanced in hypoxemic adults (2-14%). We conclude that chronic hypoxemia depresses both vascular smooth muscle and endothelial function to a greater extent in fetal than in adult cerebral arteries and that this effect could contribute to the greater postnatal vulnerability to asphyxic and hypertensive insults seen in hypoxemic neonates.

Pregnancy-induced changes in ovine cerebral arteries.

We examined the effects of pregnancy on the ovine cerebral vasculature by comparing several characteristics of isolated endothelium-intact segments of three intracranial arteries including the middle cerebral (MCA), posterior communicating (PC), and basilar (BAS) arteries taken from pregnant sheep (138-143 days gestation, term approximately 145 days) and nonpregnant controls. For comparison, segments of the extracranial common carotid (COM) artery were also studied. With pregnancy, vessel water content increased (5.4-5.8%) in all arteries except the PC. Additionally, cellular protein content increased in all arteries (4.4-50.0%). Arterial stiffness, as determined by passive stress-strain determinations, was significantly decreased during pregnancy in the MCA but not in the larger arteries. Maximum contractile responses, when normalized to vessel wall cross-sectional area, were consistently greater in arteries from pregnant than in those from nonpregnant animals (10.1-49.7%). Relaxation to the endothelium-independent guanylate cyclase stimulator S-nitroso-N-acetyl penicillamine (SNAP) increased with pregnancy only in the distal MCA (approximately 17%). Endothelium-dependent relaxation to the calcium ionophore A23187 decreased only in the larger and more proximal COM (-39%). Thus pregnancy was associated with an increase in production of contractile force, a decrease in peripheral vascular stiffness, a decrease in the relaxant response to A23187 in the COM, and an increase in the relaxant response to SNAP in the MCA. Together, these findings indicate that pregnancy has widespread and important vessel specific cerebrovascular consequences that affect not only arterial composition, but also contractility and endothelial reactivity.