Screening for Down Syndrome in the United States: Results of Surveys in 2011 and 2012

Context.—Participants in a College of American Pathologists external proficiency testing program for first and second trimester Down syndrome screening. Objectives.—To determine the number of women screened for Down syndrome in the United States, along with the type of test received and to compare those results to earlier surveys in 1988 and 1992. Design.—Questionnaires regarding the type and number of Down syndrome tests performed per month were completed by participants in early 2011 and again in early 2012. Results.—After accounting for some of the missing responses, data from up to 131 laboratories indicated that 67% (2 764 020 of 4 130 000) to 72% (2012: 2 963 592 of 4 130 000) of US pregnancies received prenatal screening for Down syndrome. Second trimester tests were most common (2012: 60%; 1 770 024 of 2 963 592), followed by integrated (2012: 21%; 627 876 of 2 963 592), and first trimester (2012: 19%; 565 692 of 2 963 592). The 6 largest laboratories tested 61% of screened pregnancies and offered the widest array of tests, while the smallest 32 tested 1% and almost always offered only second trimester tests. Conclusions.—The current population estimate of 72% pregnancies screened annually is higher than estimates from 1988 (25%) and 1992 (50%). Available testing choices are also more varied, and all testing methods perform better than those methods available 10 years ago. Clinicians should ensure that women are offered tests that follow recommended best-practice testing protocols, and screening laboratories should assess whether patient needs are being met.

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Prenatal serum screening for Down syndrome and neural tube defects in the United States: Changes in utilization patterns from 2012 to 2020

Journal of Medical Screening ◽

10.1177/09691413211031610 ◽

2021 ◽

pp. 096914132110316

Author(s):

Nathalie Lepage ◽

Philip Wyatt ◽

Edward R Ashwood ◽

Robert G Best ◽

Thomas Long ◽

...

Keyword(s):

United States ◽

Down Syndrome ◽

First Trimester ◽

The United States ◽

Maternal Serum ◽

Second Trimester ◽

Maternal Serum Screening ◽

Cell Free Dna ◽

Free Dna ◽

Serum Screening

Objective To compile current usage of serum-based prenatal screening for Down syndrome in the United States and compare it with results from a similar 2011/2012 survey. Setting The College of American Pathologists maternal screening proficiency testing survey includes a supplemental question on the first of three yearly distributions. Methods Information regarding tests offered and the monthly number of pregnancies tested for US-based laboratories were reviewed. Results were stratified by size of laboratory, tests offered, and pregnancies tested. Findings were compared to an earlier survey. Results Fifty-six laboratories reported they will have screened 1,131,336 pregnancies in 2020. Of these, 36% are screened by stand-alone first trimester testing, 48% by stand-alone second trimester testing, and 16% using tests that integrate results from both trimesters. Eighty percent of all serum screens were provided by the five laboratories that performed the most screens (at least 50,000). These five performed similar proportions of first or second trimester screens (42.2% and 41.8%, respectively). Compared to eight years earlier, there are now 54% fewer laboratories. Pregnancies screened using the first trimester, second trimester, and integrated protocols were lower by 27%, 69%, and 72%, respectively. The serum screening activity in the US showed a 62% decrease from 2012 levels. During 2012–2020, the number of cell-free DNA tests increased from negligible to 1,492,332. Conclusions Maternal serum screening for common aneuploidies has changed significantly in eight years with fewer laboratories, a shift toward larger laboratories and a 2.5-fold reduction in pregnancies tested, likely due to the introduction of cell-free DNA screening.

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Maternal Serum Invasive Trophoblast Antigen (Hyperglycosylated hCG) as a Screening Marker for Down Syndrome during the Second Trimester

Clinical Chemistry ◽

10.1373/clinchem.2004.038059 ◽

2004 ◽

Vol 50 (10) ◽

pp. 1804-1808 ◽

Cited By ~ 20

Author(s):

Glenn E Palomaki ◽

Louis M Neveux ◽

George J Knight ◽

James E Haddow ◽

Raj Pandian

Keyword(s):

United States ◽

Down Syndrome ◽

False Positive Rate ◽

The United States ◽

Maternal Serum ◽

Second Trimester ◽

Marker Panel ◽

Screening Performance ◽

Β Hcg ◽

Screening Marker

Abstract Background: Approximately two million pregnancies in the United States are screened for Down syndrome annually by use of second-trimester maternal serum markers. At present, a combination of four markers can identify 75% of affected pregnancies when 5% of screened women are classified as candidates for amniocentesis. Although not currently included in screening panels, invasive trophoblast antigen (ITA) is a promising screening marker in serum or urine in both the second and first trimesters. This study aims at better defining the screening performance of serum ITA in the second trimester. Methods: In an earlier study, serum samples from an unbiased sampling of 45 Down syndrome (cases) and 238 unaffected (control) pregnancies between 14 and 20 weeks of gestation were collected from various centers in the United States. Samples were aliquoted and stored at −20 °C for 8 years. We measured ITA in these samples and determined the screening performance both univariately and in combination with other screening markers. Results: The median ITA in Down syndrome pregnancies was >3.00 multiples of the median, higher than that found for human chorionic gonadotropin (hCG) or free β-hCG. At a 5% false-positive rate, ITA univariately detected 38% and 40% of Down syndrome pregnancies, respectively, when assigned by date of last menstrual period or ultrasound date. Modeling yielded rates of 45% and 48%. ITA correlated strongly with hCG and free β-hCG. When substituted for either of these in a multiple marker panel, ITA performed comparably. Conclusions: This study indicates that serum ITA is an effective marker for Down syndrome. It is highly correlated with both hCG and free β-hCG and could replace either of them in a multiple marker panel.

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No Legal Impediment: Access to Abortion in the United States

Journal of American Studies ◽

10.1017/s0021875800015024 ◽

1986 ◽

Vol 20 (2) ◽

pp. 189-205 ◽

Cited By ~ 1

Author(s):

A. S. Cohan

Keyword(s):

United States ◽

Pregnant Woman ◽

Medical Practitioner ◽

First Trimester ◽

The United States ◽

The State ◽

Second Trimester ◽

Life Threatening ◽

Do So

If a pregnant woman in the United States wishes to terminate her pregnancy, she may do so unimpeded by the state during the first trimester of the pregnancy, so long as the termination is performed by a registered medical practitioner. In the second trimester, she must have closer consultation with her physician than in the first three months, but the choice of an abortion still resides with her. State interest in that period may be concerned only with the safety of the procedure for the mother since abortion during the second trimester is more life-threatening to the mother than in the first. Only in the last trimester of her pregnancy does the state interest in that choice become paramount because the state finds itself in the position of being advocate for the foetus which, in thelater stages of pregnancy, may be viable outside of the mother's womb.

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Predicting the result of additional second-trimester markers from a woman's first-trimester marker profile: a new concept in Down syndrome screening

Prenatal Diagnosis ◽

10.1002/pd.1256 ◽

2005 ◽

Vol 25 (12) ◽

pp. 1102-1106 ◽

Cited By ~ 12

Author(s):

Ron Maymon ◽

Howard Cuckle ◽

Rick Jones ◽

Orit Reish ◽

Reuven Sharony ◽

...

Keyword(s):

Down Syndrome ◽

First Trimester ◽

Second Trimester ◽

Marker Profile ◽

Down Syndrome Screening

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Antenatal down syndrome screening in the united states in 2001: A survey of maternal-fetal medicine specialists

American Journal of Obstetrics and Gynecology ◽

10.1067/mob.2002.126980 ◽

2002 ◽

Vol 187 (5) ◽

pp. 1230-1234 ◽

Cited By ~ 48

Author(s):

James F.X. Egan ◽

Lillian M. Kaminsky ◽

Michael E. DeRoche ◽

Michael J. Barsoom ◽

Adam F. Borgida ◽

...

Keyword(s):

United States ◽

Down Syndrome ◽

The United States ◽

Maternal Fetal Medicine ◽

Fetal Medicine ◽

Down Syndrome Screening

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First-Trimester or Second-Trimester Screening, or Both, for Down Syndrome

50 Studies Every Obstetrician-Gynecologist Should Know ◽

10.1093/med/9780190947088.003.0020 ◽

2021 ◽

pp. 108-114

Author(s):

Jessica M. Hart ◽

Barbara M. O’Brien

Keyword(s):

Down Syndrome ◽

First Trimester ◽

Nuchal Translucency ◽

The United States ◽

Screening Tests ◽

Second Trimester ◽

Detection Rates ◽

Fully Integrated ◽

Second Trimester Screening ◽

Trimester Screening

The FASTER Trial by Malone et al. discusses methods of prenatal genetic screening for Down syndrome. The trial included 15 sites within the United States between 1999 and 2005. This trial was designed to compare the differences in detection rates of Down syndrome when applying screening tests from the first-trimester, second-trimester, or screening tests that combine markers from both trimesters. Screening tests evaluated in this trial include nuchal translucency, serum screen, combined screen, quadruple screen, independent sequential screen, stepwise sequential screen, serum integrated screen, and fully integrated screen. This trial compares detection rates, false positive rates, and timing of results between screening tests.

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Maternal Serum Invasive Trophoblast Antigen and First-Trimester Down Syndrome Screening

Clinical Chemistry ◽

10.1373/clinchem.2005.050567 ◽

2005 ◽

Vol 51 (8) ◽

pp. 1499-1504 ◽

Cited By ~ 21

Author(s):

Glenn E Palomaki ◽

George J Knight ◽

Louis M Neveux ◽

Raj Pandian ◽

James E Haddow

Keyword(s):

Down Syndrome ◽

False Positive Rate ◽

First Trimester ◽

The United States ◽

Maternal Serum ◽

Ultrasound Measurement ◽

First Trimester Screening ◽

Serum Samples ◽

Trimester Screening ◽

Down Syndrome Screening

Abstract Background: In the United States, Down syndrome screening is still performed mainly in the second trimester, using 3 or 4 markers. Moving screening into the first trimester has the advantage of earlier diagnosis. Currently, first-trimester screening typically includes maternal serum pregnancy-associated plasma protein-A (PAPP-A), the free β-subunit of human chorionic gonadotropin (free β), and ultrasound measurement of nuchal translucency thickness (NT). The current report describes a case–control study of serum invasive trophoblast antigen (ITA) and its possible inclusion in first-trimester screening for Down syndrome. Methods: As part of an earlier observational study, serum samples from 54 Down syndrome and 276 matched unaffected pregnancies were collected between 9 and 15 weeks of gestation. Samples had been aliquoted and stored at −20 °C for 8 years. ITA was measured and converted to weight-adjusted multiples of the median (MoM). The distributions of other first-trimester markers are from a single published study. Results: Median ITA MoM in Down syndrome pregnancies increase as gestational age increases (2.02 MoM at 11 and 2.44 MoM at 13 completed weeks). At 75% detection, maternal age in combination with ITA and PAPP-A measurements have an 8.0% false-positive rate, slightly lower than the 8.8% found for the free β and PAPP-A combination; adding NT measurements reduces false positives for the 2 combinations to 2.0% and 1.8%, respectively. Conclusion: Serum ITA appears to be a useful first-trimester Down syndrome marker that could replace free β measurements while maintaining performance.

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