James D. Goldberg

Genome-Wide Fetal Aneuploidy Detection by Maternal Plasma DNA Sequencing

OBJECTIVE: To prospectively determine the diagnostic accuracy of massively parallel sequencing to detect whole chromosome fetal aneuploidy from maternal plasma. METHODS: Blood samples were collected in a prospective, blinded study from 2,882 women undergoing prenatal diagnostic procedures at 60 U.S. sites. An independent biostatistician selected all singleton pregnancies with any abnormal karyotype and a balanced number of randomly selected pregnancies with euploid karyotypes. Chromosome classifications were made for each sample by massively parallel sequencing and compared with fetal karyotype. RESULTS: Within an analysis cohort of 532 samples, the following were classified correctly: 89 of 89 trisomy 21 cases (sensitivity 100%, 95% [confidence interval] CI 95.9–100), 35 of 36 trisomy 18 cases (sensitivity 97.2%, 95% CI 85.5–99.9), 11 of 14 trisomy 13 cases (sensitivity 78.6%, 95% CI 49.2–99.9), 232 of 233 females (sensitivity 99.6%, 95% CI 97.6 to more than 99.9), 184 of 184 males (sensitivity 100%, 95% CI 98.0–100), and 15 of 16 monosomy X cases (sensitivity 93.8%, 95% CI 69.8–99.8). There were no false-positive results for autosomal aneuploidies (100% specificity, 95% CI more than 98.5 to 100). In addition, fetuses with mosaicism for trisomy 21 (3/3), trisomy 18 (1/1), and monosomy X (2/7), three cases of translocation trisomy, two cases of other autosomal trisomies (20 and 16), and other sex chromosome aneuploidies (XXX, XXY, and XYY) were classified correctly. CONCLUSION: This prospective study demonstrates the efficacy of massively parallel sequencing of maternal plasma DNA to detect fetal aneuploidy for multiple chromosomes across the genome. The high sensitivity and specificity for the detection of trisomies 21, 18, 13, and monosomy X suggest that massively parallel sequencing can be incorporated into existing aneuploidy screening algorithms to reduce unnecessary invasive procedures. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT01122524. LEVEL OF EVIDENCE: II

Correction of congenital diaphragmatic hernia in utero: VI. hard-earned lessons

Extensive experimental work suggests that repair of congenital diaphragmatic hernia (CDH) in utero may salvage severely affected fetuses who otherwise have a high expected mortality despite optimal postnatal care including extracorporeal membrane oxygenation (ECMO). We have reported that repair of CDH in utero is physiologically sound and safe for the mother, but technically difficult especially when the liver is herniated into the fetal chest. In the 3 years since our last report (1989 to 1991), 61 additional patients were referred for consideration of in utero repair. Fetal repair was attempted in 14 with severe isolated left CDH diagnosed before 24 weeks gestation. Five fetuses died intraoperatively, from technical problems related to reduction of incarcerated liver and uterine contractions--problems which have subsequently been surmounted. Nine patients were successfully repaired. Four babies survived, two delivered prematurely and died, and three died in utero within 48 hours of repair. Intraoperative technical problems have been overcome; the factors limiting successful outcome are postoperative physiologic management of the maternal-fetal unit and effective tocolysis to control preterm labor.

Noninvasive prenatal testing and incidental detection of occult maternal malignancies

IMPORTANCE Understanding the relationship between aneuploidy detection on noninvasive prenatal testing (NIPT) and occult maternal malignancies may explain results that are discordant with the fetal karyotype and improve maternal clinical care. OBJECTIVE To evaluate massively parallel sequencing data for patterns of copy-number variations that might prospectively identify occult maternal malignancies. DESIGN, SETTING, AND PARTICIPANTS Case series identified from 125,426 samples submitted between February 15, 2012, and September 30, 2014, from asymptomatic pregnant women who underwent plasma cell-free DNA sequencing for clinical prenatal aneuploidy screening. Analyses were conducted in a clinical laboratory that performs DNA sequencing. Among the clinical samples, abnormal results were detected in 3757 (3%); these were reported to the ordering physician with recommendations for further evaluation. EXPOSURES NIPT for fetal aneuploidy screening (chromosomes 13, 18, 21, X, and Y). MAIN OUTCOMES AND MEASURES Detailed genome-wide bioinformatics analysis was performed on available sequencing data from 8 of 10 women with known cancers. Genome-wide copy-number changes in the original NIPT samples and in subsequent serial samples from individual patients when available are reported. Copy-number changes detected in NIPT sequencing data in the known cancer cases were compared with the types of aneuploidies detected in the overall cohort. RESULTS From a cohort of 125,426 NIPT results, 3757 (3%) were positive for 1 or more aneuploidies involving chromosomes 13, 18, 21, X, or Y. From this set of 3757 samples, 10 cases of maternal cancer were identified. Detailed clinical and sequencing data were obtained in 8. Maternal cancers most frequently occurred with the rare NIPT finding of more than 1 aneuploidy detected (7 known cancers among 39 cases of multiple aneuploidies by NIPT, 18% [95% CI, 7.5%-33.5%]). All 8 cases that underwent further bioinformatics analysis showed unique patterns of nonspecific copy-number gains and losses across multiple chromosomes. In 1 case, blood was sampled after completion of treatment for colorectal cancer and the abnormal pattern was no longer evident. CONCLUSIONS AND RELEVANCE In this preliminary study, a small number of cases of occult malignancy were subsequently diagnosed among pregnant women whose noninvasive prenatal testing results showed discordance with the fetal karyotype. The clinical importance of these findings will require further research.

Selective termination for structural, chromosomal, and mendelian anomalies: International experience

OBJECTIVE Our purpose was to evaluate the outcomes of selective termination for fetal anomalies at 8 centers with the largest known experiences worldwide. STUDY DESIGN Outcomes in 402 cases of selective termination in pregnancies with dizygotic twins from 8 centers in 4 countries were analyzed by year, gestational age at procedure, and indication. Reductions of fetuses were as follows: 2 to 1, n = 345; 3 to 2, 39; >/=4 to 2 or 3, n = 18. Potassium chloride was used in all procedures. RESULTS Selective termination resulted in delivery of a viable infant or infants in >90% of cases. Loss up to 24 weeks occurred in 7.1% of cases in which the final result was a singleton fetus and in 13.0% of cases in which the final result was twins. Loss was 6.6% as a result of structural abnormalities, 7.0% for chromosomal abnormalities, and 10% for mendelian abnormalities (difference not statistically significant). Loss rates for procedures were as follows: 9-12 weeks, 5.4%; 13-18 weeks, 8.7%; 19-24 weeks, 6.8%; and >/=25 weeks, 9.1% (difference not statistically significant). Mean gestational age at delivery was 35.7 weeks. No differences were seen in outcomes by maternal age. The rate of very early premature deliveries has fallen in recent years. There were no known cases of disseminated intravascular coagulation or serious maternal complications. CONCLUSION (1) Selective termination, in the most experienced hands, can be technically performed in all 3 trimesters with good outcomes in >90% of cases. (2) The previously observed increase in second- versus first-trimester losses has diminished. (3) Third-trimester procedures, where legal, can be performed with a good outcome for the surviving fetus.

Efficacy of second-trimester selective termination for fetal abnormalities: International collaborative experience among the world's largest centers

OBJECTIVE Our goal was to develop the most comprehensive database possible to counsel patients about selective termination for fetal abnormalities, because no one center has sufficient data to assess much more than crude loss rates. STUDY DESIGN A total of 183 completed cases of selective termination from 9 centers in 4 countries were combined (169 twins, 11 triplets, 3 quadruplets). Variables included indications, methods, (potassium chloride, exsanguination, air embolus), gestational age at procedure, pregnancies lost (< or = 24 weeks), gestational age at delivery, and neonatal outcome. RESULTS Indications for selective termination were 96 chromosomal, 76 structural, and 11 mendelian. Selective termination was technically successful in 100% of cases. In 23 of 183 (12.6%) miscarriage occurred before 24 weeks; 2 of 37 (5.4%) occurred when the procedure done at < or = 16 weeks and 21 of 146 (14.4%) when it was done thereafter. Air embolization had a higher loss rate: 10 of 24 (41.7%) compared with 13 of 156 (8.3%) by potassium chloride (chi 2 = 117, p < 0.0001). Three cases of selective termination performed in monochorionic pregnancies all resulted in pregnancy loss. Among 183 potentially viable deliveries, 7 occurred before 28 weeks, 19 at 29 to 32 weeks, 41 at 33 to 36 weeks, and 93 at > or = 37 weeks. Gestational age at delivery was not influenced by the technique used or the indication but was negatively correlated with gestational age at the time of selective termination. No coagulopathy or ischemic damage was observed in survivors. There was no maternal morbidity. CONCLUSIONS (1) Selective termination in experienced hands for a dizygotic abnormal twin is safe and effective when done with potassium chloride. A total of 83.8% of viable deliveries occurred after 33 weeks and only 4.3% at 25 to 28 weeks. (2) Gestational age at the procedure correlated positively with loss rate and inversely with gestational age at delivery; this emphasizes the need for early diagnosis in multifetal pregnancies. (3) Coagulopathy tests are probably unnecessary.

Expanded carrier screening in reproductive medicine-points to consider: a joint statement of the American College of Medical Genetics and Genomics, American College of Obstetricians and Gynecologists, National Society of Genetic Counselors, Perinatal Quality Foundation, and Society for Maternal-Fetal Medicine.

The Perinatal Quality Foundation and the American College of Medical Genetics and Genomics, in association with the American College of Obstetricians and Gynecologists, the Society for Maternal-Fetal Medicine, and the National Society of Genetic Counselors, have collaborated to provide education for clinicians and laboratories regarding the use of expanded genetic carrier screening in reproductive medicine. This statement does not replace current screening guidelines, which are published by individual organizations to direct the practice of their constituents. As organizations develop practice guidelines for expanded carrier screening, further direction is likely. The current statement demonstrates an approach for health care providers and laboratories who wish to or who are currently offering expanded carrier screening to their patients.

Transabdominal versus transcervical and transvaginal multifetal pregnancy reduction: International collaborative experience of more than one thousand cases * ** *

OBJECTIVES Two major approaches for multifetal pregnancy reduction have been developed over the past several years: transabdominal potassium chloride by injection and pelvic procedures by either transcervical aspiration or transvaginal potassium chloride injection or by an automated spring-loaded puncture device. The purpose of this study was to create the largest database from among the worlds largest centers to assess possible differences in efficacy and complication rates by transabdominal or transcervical or multifetal pregnancy reduction. STUDY DESIGN Data on over 1000 completed pregnancies that underwent multifetal pregnancy reduction by both methods from major centers with among the highest worldwide experience were combined. Transabdominal cases were divided temporally (1986 through 1991 and 1991 through 1993). RESULTS Transabdominal multifetal pregnancy reduction was successfully performed on 846 patients and transcervical or transvaginal on 238 patients. Transcervical or transvaginal reduction is performed earlier and starts and finishes with fewer embryos. In 12.6% of cases transcervical or transvaginal reduction left a singleton as opposed to 4.4% for transabdominal reduction. Pregnancy losses (up to 24 weeks) were observed in 13.1% of transcervical or transvaginal cases and in 16.2% of transabdominal cases early in the series and 8.8% of late transabdominal cases. Transcervical or transvaginal reduction may be safer very early in gestation and transabdominal safer later in the first trimester. Premature deliveries were comparable, with only about 5% delivered between 25 and 28 weeks. The smaller starting numbers for transcervical and transvaginal reduction may explain a slightly higher term delivery rate. The transabdominal route tends to reduce the fundal embryos and the transcervical and transvaginal the lower ones. The significance of this is not clear. CONCLUSIONS (1) Multifetal pregnancy reduction by either method is a relatively safe and efficient method for improving outcome in multifetal pregnancies. (2) More than 84% are delivered at > 33 weeks. (3) The experience and preference of the operator are probably the key determinants for an individual patient. (4) An inverse relationship of starting and finishing number to loss rates and gestational age at delivery suggests that there still is a cost of iatrogenic multifetal pregnancies, even if multifetal pregnancy reduction can be successfully performed.

Fetal Magnetic Resonance Imaging in the Evaluation of Fetuses Referred for Sonographically Suspected Abnormalities of the Corpus Callosum

Fetal magnetic resonance imaging (MRI) has been shown to be useful in assessing the developing central nervous system. However, its utility in specific brain disorders has not been well investigated. We hypothesized that fetal MRI can better assess the integrity of the brain in cases with sonographically suspected callosal abnormalities.

Cytogenetic results of chorionic villus sampling: high success rate and diagnostic accuracy in the United States collaborative study.

Cytogenetic results of first-trimester chorionic villus sampling are reported from seven U.S. medical centers. For 6033 patients who had a successful chorionic villus sampling procedure, the rate for obtaining a cytogenetic diagnosis was 99.6% with the direct method, long-term culture, or both. There were no incorrect sex predictions and no diagnostic errors involving trisomies 21, 18, or 13, sex chromosome aneuploidies, or structural abnormalities. There were no cases of normal cytogenetic diagnosis followed by birth of a cytogenetically abnormal infant. Three cases of unusual aneuploidies (tetraploidy, trisomy 16, and trisomy 22) detected by the direct method only were not confirmed by cytogenetic follow-up. Mosaic cytogenetic abnormalities were observed in 0.83% of all cases in which chorionic villus sampling was done but were confirmed by amniocentesis or in fetal tissues in only 7 of 30 cases (23.3%). Maternal cell contamination occurred in 1.9% of long-term cultures, although this did not present any cytogenetic diagnostic difficulties. Overall, a very high degree of laboratory success and diagnostic accuracy was observed with either cytogenetic method, although fewer predictive errors were observed with the long-term culture method and none were observed when both methods were used.

American College of Medical Genetics Statement on Diagnostic Testing for Uniparental Disomy

American College of Medical Genetics Statement on Diagnostic Testing for Uniparental Disomy