Implementation of fetal clinical exome sequencing: Comparing prospective and retrospective cohorts.

PURPOSE: We compared the diagnostic yield of fetal clinical exome sequencing (fCES) in prospective and retrospective cohorts of pregnancies presenting with anomalies detected using ultrasound. We evaluated factors that led to a higher diagnostic efficiency, such as phenotypic category, clinical characterization, and variant analysis strategy. METHODS: fCES was performed for 303 fetuses (183 ongoing and 120 ended pregnancies, in which chromosomal abnormalities had been excluded) using a trio/duo-based approach and a multistep variant analysis strategy. RESULTS: fCES identified the underlying genetic cause in 13% (24/183) of prospective and 29% (35/120) of retrospective cases. In both cohorts, recessive heterozygous compound genotypes were not rare, and trio and simplex variant analysis strategies were complementary to achieve the highest possible diagnostic rate. Limited prenatal phenotypic information led to interpretation challenges. In 2 prospective cases, in-depth analysis allowed expansion of the spectrum of prenatal presentations for genetic syndromes associated with the SLC17A5 and CHAMP1 genes. CONCLUSION: fCES is diagnostically efficient in fetuses presenting with cerebral, skeletal, urinary, or multiple anomalies. The comparison between the 2 cohorts highlights the importance of providing detailed phenotypic information for better interpretation and prenatal reporting of genetic variants.

Cell-free DNA analysis in maternal blood: comparing genome-wide versus targeted approach as a first-line screening test.

OBJECTIVES: To evaluate the failure rate and performance of cell-free DNA (cfDNA) testing as a first-line screening method for major trisomies, performed by two laboratories using different analytical methods: a targeted chromosome-selective method (Harmony® prenatal Test) versus a home-brew genome-wide (GW) massively parallel sequencing method (HB-cfDNA test), and to evaluate the clinical value of incidental findings for the latter method. METHODS: CfDNA testing was performed in 3137 pregnancies with the Harmony® prenatal Test and in 3373 pregnancies with the HB-cfDNA test. Propensity score analysis was used to match women between both groups for maternal age, weight, gestational age at testing, in vitro fertilization, rate of twin pregnancies and that of aneuploidies. Detection rates for trisomy 21 were compared between the 2 laboratories. For the HB-cfDNA test, cases with rare incidental findings were reported, including their clinical follow-up. RESULTS: The Harmony® prenatal Test failed at the first attempt in 90 (2.9%) of 3114 women and the HB-cfDNA test in 413 (12.2%) of 3373 women. Postmatched comparisons of the women's characteristics indicate a significantly lower failure rate in the Harmony® group (2.8%) than in the HB cfDNA group (12.4%; p < .001). Of the 90 women in whom the Harmony® prenatal Test failed, 61 had a repeat test, which still failed in 10, and of the 413 women in whom the HB-cfDNA test failed, 379 had a repeat test, which still failed in 110. The total failure rate after one or two attempts was therefore 1.3% (39/3114) for Harmony® and 4.3% (144/3373) for the HB cfDNA test. After the first or second Harmony® prenatal Test, a high-risk result was noted in 17 of the 17 cases with trisomy 21, in 5 of the seven cases with trisomy 18, and a no-call in two cases, and in the one case with trisomy 13. The respective numbers for the HB-cfDNA test are 17 of the 18 cases with trisomy 21, and a no-call in one case, 2 of the two cases with trisomy 18, and in 2 of the three cases with trisomy 13, and a no-call in one. Of the 3373 women with the HB-cfDNA test, a rare incidental finding was noted in 28 (0.8%) of the cases, of which only 2 were confirmed on amniocytes (one with microduplication 1q21.1q21.2 and one with a deletion Xp21.1), and in another case a deletion rather than a duplication of the long arm of chromosome 8 was found. In all 28 cases, there was normal clinical follow-up. CONCLUSIONS: Comparison of cfDNA testing between these two laboratories showed a four-fold lower failure rate with the Harmony® prenatal Test, with a similar detection rate for trisomy 21. We showed no clinical relevance of disclosing additional findings beyond common trisomies with the GW HB-cfDNA test.

Relationship between vitamin D status in pregnancy and the risk for preeclampsia: A nested case-control study.

BACKGROUND & AIMS: Vitamin D is thought to be involved in the pathogenesis of preeclampsia. To evaluate the relationship between vitamin D insufficiency in the first trimester of pregnancy and preeclampsia. METHODS: Nested case-control study (FEPED study) in type 3 obstetrical units. Pregnant women from 10 to 15 WA. For each patient with preeclampsia, 4 controls were selected from the cohort and matched by parity, skin color, maternal age, season and BMI. The main outcome measure was serum 25(OH)D status in the first trimester. RESULTS: 83 cases of preeclampsia were matched with 319 controls. Mean 25(OH)D levels in the first trimester were 20.1 ± 9.3 ng/mL in cases and 22.3 ± 11.1 ng/mL in controls (p = 0.09). The risk for preeclampsia with 25(OH)D level ≥30 ng/mL in the first trimester was decreased, but did not achieve statistical significance (OR, 0.57; 95% CI, 0.30-1.01; p = 0.09). High 25(OH)D during the 3rd trimester was associated with a significantly decreased risk of preeclampsia (OR, 0.43; 95%CI, 0.23-0.80; p = 0.008). When women with 25(OH)D levels <30 ng/mL both in the first and 3rd trimesters ("low-low") were taken as references, OR for preeclampsia was 0.59 (95% CI, 0.31-1.14; p = 0.12) for "low-high" or "high-low" women and 0.34 (95% CI, 0.13-0.86; p = 0.02) for "high-high" women. CONCLUSIONS: No significant association between preeclampsia and vitamin D insufficiency in the first trimester was evidenced. However, women with vitamin D sufficiency during the 3rd trimester and both in the first and 3rd trimesters had a significantly lower risk of preeclampsia.

Vitamin D status during pregnancy and in cord blood in a large prospective French cohort.

BACKGROUND & AIMS: Vitamin D status during pregnancy and in newborns has never been studied in France. This study aims at determining the vitamin D status during the first and third trimesters of pregnancy (T1, T3) and in cord blood (CB) in the middle-north of France. METHODS: We conducted a prospective cohort study in five French centers (latitude 47.22 to 48.86°N). Serum 25(OH)-vitamin D (25(OH)D) concentrations were measured using a radioimmunoassay during T1, T3 and in CB. According to the French guidelines, pregnant women received cholecalciferol, 100,000 IU, in the seventh month. RESULTS: Between April 2012 and July 2014, 2832 women were included, of whom 2803 were analyzed (mean ± SD age: 31.5 ± 5.0 years; phototypes 5-6: 21.8%). Three and 88.6% of participants received supplementation during the month before inclusion and in the seventh month, respectively. At T1, T3, and CB, mean 25(OH)D concentrations were 21.9 ± 10.4, 31.8 ± 11.5, and 17.0 ± 7.2 ng/mL, respectively, and 25(OH)D was <20 ng/mL in 46.5%, 14.0%, and 68.5%, respectively. At T1, body mass index ≥25 kg/m2, dark phototypes, sampling outside summer, and no supplementation before inclusion were independently associated with vitamin D insufficiency (25(OH)D < 20 ng/mL). Women who received cholecalciferol supplementation in month 7 had higher 25(OH)D at T3 than non-supplemented women (32.5 ± 11.4 versus 25.8 ± 11.4 ng/mL, p = <0.001) and marginally higher 25(OH)D in CB (17.2 ± 7.2 versus 15.5 ± 7.1 ng/mL, p = 0.004). CONCLUSIONS: Despite the recommended supplementation, vitamin D insufficiency is frequent during pregnancy and in newborns in France.

First-Trimester Combined Multimarker Prospective Study for the Detection of Pregnancies at a High Risk of Developing Preeclampsia Using the Fetal Medicine Foundation-Algorithm.

OBJECTIVE: To evaluate the Fetal Medicine Foundation (FMF) algorithm prospectively at 11-13 weeks' gestation in the prediction of preeclampsia (PE). METHODS: Single-center prospective screening study for PE of singleton pregnancies at 11-13 weeks. The FMF algorithm takes into account maternal characteristics and biomarkers. Detection rate (DR) for a 10% false-positive rate (FPR) for delivery with preterm and term PE was estimated. RESULTS: Between January 2011 and December 2013, of 3,239 patients available for final analysis, 36 (1.1%) subsequently developed preterm and 44 (1.4%) term PE. In combined screening by maternal factors, mean arterial pressure, uterine artery pulsatility index, and serum placental growth factor, the DR was 80.6% (95% CI 64.0-91.8) for PE at <37 weeks and 31.8% (95% CI 18.6-47.6) for PE at ≥37 weeks, at a 10% FPR. CONCLUSION: Our data suggest that the FMF algorithm provides effective first-trimester screening for preterm PE.

Parental acceptance of minimally invasive fetal and neonatal autopsy compared with conventional autopsy.

OBJECTIVE: To determine parental acceptance of minimally invasive autopsy (MIA) involving postmortem imaging and organ tissue sampling compared with conventional autopsy and to compare the acceptability of percutaneous versus laparoscopic-guided biopsy. METHODS: Following termination of pregnancy parents were offered the option of traditional autopsy and subsequently interviewed about their acceptance of MIA. The McNemar test for paired samples was used to assess the difference in acceptance of MIA and conventional autopsy. The Wilcoxon signed-rank test for paired samples was used to compare the acceptance score for percutaneous versus laparoscopic-guided biopsy. Logistic regression was selected to study the association of parental acceptance of conventional autopsy and MIA with different variables. RESULTS: Conventional autopsy was accepted by 42 (60.0%) of the 70 parents. Regression analysis showed that non-Muslim faith was the only factor significantly associated with acceptance of conventional autopsy (p = 0.030). Of 28 parents who initially refused conventional autopsy, 13(46.4%) subsequently accepted MIA, increasing acceptance to 78.6% (p < 0.001). Regression analysis showed that none of the factors significantly affected MIA acceptance. Parents expressed no preference between postmortem percutaneous versus laparoscopic-guided biopsy (p = 0.061). CONCLUSION: Post-mortem imaging combined with systematic organ biopsies is highly acceptable among all parents independent of their religion and the method used for organ biopsy.

Evidence of human papillomavirus in the placenta.

Human papillomavirus (HPV) is an epitheliotropic virus typically infecting keratinocytes but also possibly epithelial trophoblastic placental cells. In the present study, we set out to investigate whether HPV can be recovered from transabdominally obtained placental cells to avoid any confounding contamination by HPV-infected cervical cells. Thirty-five placental samples from women undergoing transabdominal chorionic villous sampling were analyzed, and we detected HPV-16 and HPV-62 in 2 placentas. This study suggests that HPV infection of the placenta can occur early in pregnancy. The overall clinical implication of these results remains to be elucidated.