Prospective sonographic detection of spina bifida at 11-14 weeks and systematic literature review.

OBJECTIVE: To conduct a literature review to assess the effectiveness of first trimester ultrasonographic markers of spina bifida (SB) integrating data with our prospective experience. METHODS: The analysis of the SB cases that we prospectively detected in the first trimester, between January 2012 and February 2014, and a systematic review of all the papers evaluating the effectiveness of SB ultrasonographic markers at 11-14 weeks, namely brain stem diameter (BS), fourth ventricle/intracranial translucency (IT), cisterna magna (CM), brain stem/occipital bone distance (BSOB), the ratio between BS and BSOB. Some studies assess only the effectiveness of IT, others include more parameters, and few include them all. RESULTS: We prospectively detected four SB cases, three open (OSB) and one closed (CSB), in a low risk population undergoing first trimester screening. In the three OSB, CM (in 2/3 cases) and BSOB (3/3) distance were below the 5th percentile, BS and BS/BSOB ratio (3/3) were above the 95th percentile. In the CSB, all the measurements were within normal limits. CONCLUSION: The literature and our data agree that most fetuses with OSB demonstrate in the first trimester positive sonographic markers in the posterior fossa, but additional prospective studies are needed to establish the best protocol for OSB screening.

Simplified first-trimester fetal cardiac screening (four chamber view and ventricular outflow tracts) in a low-risk population.

OBJECTIVES: Our aim was to assess the accuracy of a simplified fetal cardiac study, inclusive of four-chamber view (4CV) and ventricular outflow tracts, performed during the 11-14 week screening by well-trained obstetricians to detect congenital heart diseases (CHDs). METHODS: A transabdominal ultrasound was performed on 4820 singleton pregnant women at 11-14 weeks to visualize the visceral site, the 4CV, and the outflow tracts. Neonatal outcomes were recorded 6 and 12 months after birth. RESULTS: Among the 4820 patients reviewed, 790 were excluded because of loss at prenatal or postnatal follow-up (649 cases), or inability to obtain adequate first-trimester sonographic cardiac evaluation (141 cases). Among the 4030 included cases, 32 CHD cases were detected (20 major and 12 minor); 18 of the major (90%) and five of the minor (42%) were detected or suspected in the first trimester, one major and six minor in the second trimester, and one major and one minor only after birth. CONCLUSIONS: A simplified protocol is an effective tool to screen for CHD at 11-14 weeks.

First-trimester screening for trisomy-21 using a simplified method to assess the presence or absence of the fetal nasal bone.

OBJECTIVE: To determine the benefit of including nasal bone assessment in addition to standard first-trimester markers (nuchal translucency, free beta human chorionic gonadotropin and pregnancy-associated plasma protein A) as a screening test for Down syndrome, using a strict criterion for classification of nasal bone absence. STUDY DESIGN: Nasal bone assessment was conducted in 2411 patients with crown-rump length between 45 and 84 mm, including 15 patients with Down syndrome. A patient was considered to have an absent nasal bone only if there was no evidence of present nasal bone. Unlike other studies, nasal bone was classified as present when there was evidence of a thin echogenic line under the skin. Simulation studies were conducted to assess the detection rate and false-positive rate of a combined first-trimester screening protocol including nasal bone assessment. RESULTS: There were 9 of 2396 (0.4%) unaffected cases with absent nasal bone (95% confidence interval 0.2%, 0.7%) and 8 of 15 (53.3%) Down syndrome cases (95% confidence interval 26.6%, 78.7%). Using a 1 in 250 risk cut-off, the detection rate of standard first-trimester screening was 87%, with a false-positive rate of 4.3%. Incorporating nasal bone measurement improved the detection rate of Down syndrome to 90% and reduced the false-positive rate to 2.5%. CONCLUSION: The use of a strict criterion to determine nasal bone absence leads to fewer cases classified as absent and may simplify the implementation of nasal bone as a marker for first-trimester screening, resulting in lower false-positives and higher detection, compared with other current screening protocols.

First trimester screening with free beta-hCG, PAPP-A and nuchal translucency in pregnancies conceived with assisted reproduction.

OBJECTIVE: To evaluate the effect of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) on free beta-human chorionic gonadotrophin (beta-hCG), pregnancy-associated plasma protein A (PAPP-A) and nuchal translucency (NT). METHODS: First trimester maternal dried whole blood specimens from 74 singleton pregnancies (32 by IVF and 42 by ICSI) and 30 twin pregnancies (16 by IVF and 14 by ICSI) in which conception was achieved with assisted reproduction techniques were matched with five controls resulting in 370 singleton controls and 150 twin controls. NT was measured using the Fetal Medicine Foundation protocol. Free beta-hCG, PAPP-A and NT levels were compared between the IVF and control groups and between the ICSI and control groups using the Mann-Whitney U test. RESULTS: In singleton pregnancies, the only significant difference was a 21% (95% CI: -35%--7%) reduction in PAPP-A in IVF cases. In twin pregnancies, the only significant difference was a 12% (95% CI: -34%--3%) reduction in NT in IVF cases. In singleton pregnancies, the false-positive rate for Down syndrome screening was 1.4% and 1.9% greater for the IVF and ICSI groups, respectively, compared to controls for a general screening population. CONCLUSIONS: Patients undergoing assisted reproduction techniques should be counseled about the possibility of increased false-positive rates. Larger studies are needed to confirm this observation and to develop appropriate adjustment factors to reduce false-positive rates.