Nuchal translucency thickness in the prediction of unbalanced translocations.

OBJECTIVE: The aim of this study was to assess the role of nuchal translucency (NT) in the prediction of unbalanced translocation in offspring of couples in which one of the parents is a balanced translocation carrier. MATERIAL AND METHODS: From January 1996 to December 2012, fetal NT was measured before chorionic villus sampling in 86 pregnancies referred because of parental balanced translocation. RESULTS: No significant differences in pregnancy characteristics and in NT expressed in millimetres or in multiples of the median (MoMs) were observed between the 41 fetuses with a normal karyotype [1.72 mm, 95% confidence interval (CI): 1.49-1.96; 1.14 MoM; 95% CI: 1.01-1.26], the 38 fetuses with balanced translocations (1.78 mm, 95% CI: 1.44-2.12; 1.22 MoM; 95% CI: 1.01-1.43) and the 7 fetuses with unbalanced translocations (2.21 mm, 95% CI: 1.33-3.09; 1.59 MoM; 95% CI: 0.72-2.45). The proportions of fetuses with NT above 95th centile in the three groups were 9.1% in fetuses with normal karyotype, 18.4% in balanced translocations and 28.6% in unbalanced translocations, not significantly different. CONCLUSION: Although a trend to an increased NT was observed in fetuses with unbalanced translocation, no significant differences were reached. According to our results, a normal NT evaluation should not preclude the performance of CVS in pregnancies of balanced translocation parents.

Likelihood ratios to apply for nasal bone, ductus venosus and tricuspid flow at the 11-13 weeks' scan in down syndrome screening.

OBJECTIVE: To assess the feasibility of nasal bone (NB), ductus venosus (DV) and tricuspid flow (TF) at the 11-13 weeks' scan, calculate likelihood ratios for each of the markers and evaluate their efficacy in expanded and contingent screening strategies for Down syndrome. MATERIAL AND METHODS: NB, DV and TF were assessed in 11,261 singleton fetuses undergoing first trimester combined screening. For each marker, Down syndrome detection rate (DR), false positive rate (FPR), positive, negative and isolated likelihood ratios (PLR, NLR and iLR) were calculated. Likelihood ratios were multiplied to the combined test risk either to the entire population or to the intermediate risk group (expanded and sequential strategies, respectively). RESULTS: Down syndrome was diagnosed in 101 pregnancies. Feasibility for marker assessment ranged from 71 to 97%, DRs for isolated markers from 20 to 54% and FPRs from 1.3 to 5.3%. PLR ranged from 10 to 15, NLR from 0.5 to 0.8 and iLR from 3.9 to 5.6. When ultrasound markers were added to both strategies, a significant FPR reduction was observed. CONCLUSION: The application of NB, DV and TF likelihood ratios to the combined test risk, either in an expanded or contingent strategy, result in a FPR reduction.

Use of fetal nuchal translucency in the first trimester to predict single-gene disorders.

OBJECTIVE: To assess the predictive value of fetal nuchal translucency (NT) measurement in the prenatal diagnosis of single-gene disorders. METHODS: From January 1996 to December 2006, fetal NT was prospectively measured before chorionic villi sampling in 169 pregnancies at high risk for a single-gene disorder at 11 to 13 weeks of pregnancy. RESULTS: No differences were found between the 63 affected and 116 nonaffected fetuses in pregnancy demographic characteristics, in mean NT measurements, expressed either in millimetres [1.8 (95% CI:1.6-1.9) vs 1.7 (95% CI:1.6-1.8)] or in multiples of the median [1.19 (95%CI: 1.04-1.35) vs 1.14 (95%CI: 1.05-1.23)], or in median NT. The percentage of increased NT above the 95(th) percentile was similar for affected (9.5%) and nonaffected (11.2%) fetuses. CONCLUSION: Not all single-gene disorders are associated with enlarged NT, therefore NT cannot be regarded as a generic marker for single-gene disorder but only for a limited number of these conditions.

Evolution of prenatal detection of neural tube defects in the pregnant population of the city of Barcelona from 1992 to 2006.

OBJECTIVES: To assess the prenatal ultrasound detection rates (DR) of neural tube defects (NTDs) and its evolution over the 1992 to 2006 period in the pregnant population of the city of Barcelona. METHODS: Data on the population-based register of birth defects were used to assess the evolution of the prenatal DR for isolated NTD, including anencephaly, spina bifida and encephalocele by trimester of gestation. RESULTS: In the register, 127 isolated NTD cases, including 71 anencephalic fetuses, 49 spina bifidas and 7 encephaloceles were noted. Overall, prenatal ultrasound DR for isolated NTD was 94%. All fetuses with anencephaly or encephalocele were prenatally detected (100% DR), whereas DR for spina bifida was 84%, with no apparent variation over the observation period. An important increase in first trimester DRs was observed for anencephaly, rising from 16% in the first years of the study (1992-1996) to 71% in the last years (2002-2006). CONCLUSION: A high DR (94%) for isolated NTD was observed in the city of Barcelona. The single significant change across the study period was an increase in the first trimester DR for anencephaly (from 16% to 71%).

Chromosomal anomaly spectrum in early pregnancy loss in relation to presence or absence of an embryonic pole.

OBJECTIVE: To compare the cytogenetic findings in a series of missed miscarriages evaluated by chorionic villus sampling, in relation to embryonic pole presence (embryonic or anembryonic). DESIGN: Prospective cross-sectional study. SETTING: Tertiary referral hospital. PATIENT(S): Women presenting with a missed miscarriage. INTERVENTION(S): Transcervical chorionic villus sampling and cytogenetic studies in the chorionic villi with use of the semidirect method. MAIN OUTCOME MEASURES(S): Embryonic pole presence or absence assessed by transvaginal ultrasound examination. Type of chromosomal anomalies found in both subgroups. RESULT(S): Although the chromosomal abnormality rate was similar for miscarriages with absent or present embryo (61% vs. 68% respectively), frequencies for viable autosomal trisomies (2.3% vs. 19%) and monosomy X (0% vs. 9.2%) were significantly lower when no embryonic pole was seen. CONCLUSION(S): Viable autosomal trisomies and monosomies X appear not to be a common cause of miscarriage with an early fetal demise (anembryonic miscarriage).

Unintended pregnancy after gonadal failure chemoprevention with gonadotropin-releasing hormone agonist in women with hematologic malignancies.

Many patients who receive co-treatment with GnRH agonists (GnRH-a) during chemotherapy treatment preserve their ovarian function and are at risk of unintended pregnancies. Therefore, it is important to offer them effective contraception. Also, pregnancies occurring after cancer therapy in women who received GnRH-a are not associated with adverse neonatal outcomes.