{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T08:06:49Z","timestamp":1763366809740},"reference-count":8,"publisher":"Wiley","issue":"12","license":[{"start":{"date-parts":[[2005,12,14]],"date-time":"2005-12-14T00:00:00Z","timestamp":1134518400000},"content-version":"vor","delay-in-days":3666,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Prenatal Diagnosis"],"published-print":{"date-parts":[[1995,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>We have applied our multimarker approach of maternal serum alpha\u2010fetoprotein (AFP) and free\u2010beta human chorionic gonadotropin (hCG) for Down syndrome screening to multiple gestations to assess its efficacy for improved detection of twin and triplet pregnancies. This study matched 225 cases of twin pregnancy and 39 cases of triplet pregnancy each with ten singleton pregnancies based on gestational week, race, time to receive sample, time of year of sample, and geographical area. The ratios of the MOM for each group at the tenth, 50th, and 90th percentiles were compared by the Wilcoxon test. Risks for twins were calculated using Bayes' rule, the age\u2010related incidence of twins, and the levels of AFP and free\u2010beta hCG. The tenth, 50th, and 90th percentiles of free\u2010beta hCG MOMs in twin and triplet cases were 0.85, 1.99, and 4.51, and 1.38, 2.78, and 4.07, respectively. For AFP, the MOMs at these percentiles were 1.26, 1.91, and 2.99, and 2.02, 2.68, and 5.30, respectively. The twin and triplet distributions for each marker were statistically significantly different from the singleton distributions (<jats:italic>P<\/jats:italic>&lt;0.0001) and from each other (<jats:italic>P<\/jats:italic>=0.0012). At a twin risk cut\u2010off of 1 in 50, 77.4 per cent of all twin gestations can be detected in a second\u2010trimester AFP and free\u2010beta hCG screening protocol with 5.1 per cent of singleton pregnancies falsely identified as at risk for twins. Our dual marker protocol for mid\u2010trimester pregnancy screening combining AFP and free\u2010beta hCG can identify over 77 per cent of twin pregnancies in women less than 35 years of age. This benefit may contribute to an improved outcome of pregnancy by early detection of multiple gestation.<\/jats:p>","DOI":"10.1002\/pd.1970151209","type":"journal-article","created":{"date-parts":[[2007,3,4]],"date-time":"2007-03-04T10:10:24Z","timestamp":1173003024000},"page":"1131-1134","source":"Crossref","is-referenced-by-count":14,"title":["Enhanced twin pregnancy detection within an open neural tube defect and down syndrome screening protocol using free\u2010beta hCG and AFP"],"prefix":"10.1002","volume":"15","author":[{"given":"Vanessa M.","family":"Barnabei","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David A.","family":"Krantz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"James N.","family":"Macri","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"suffix":"Jr","given":"John W.","family":"Larsen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2005,12,14]]},"reference":[{"key":"e_1_2_1_2_1","first-page":"189","article-title":"A randomized trial of routine prenatal ultrasound","volume":"76","author":"Ewigman B.","year":"1990","journal-title":"Obstet. Gynecol."},{"key":"e_1_2_1_3_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM199309163291201"},{"key":"e_1_2_1_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9378(90)91308-Y"},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.1970140204"},{"key":"e_1_2_1_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/0140-6736(90)91941-3"},{"issue":"50","key":"e_1_2_1_7_1","first-page":"1","article-title":"Health and demographic characteristics of twin births: United States, 1988","volume":"21","author":"Taffel S. M.","year":"1992","journal-title":"Vital Health Stat."},{"key":"e_1_2_1_8_1","unstructured":"Vital Statistics of the United States 1991(1995).Natality in press."},{"key":"e_1_2_1_9_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.1970140415"}],"container-title":["Prenatal Diagnosis"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fpd.1970151209","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/pd.1970151209","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,26]],"date-time":"2023-10-26T03:09:58Z","timestamp":1698289798000},"score":1,"resource":{"primary":{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/10.1002\/pd.1970151209"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1995,12]]},"references-count":8,"journal-issue":{"issue":"12","published-print":{"date-parts":[[1995,12]]}},"alternative-id":["10.1002\/pd.1970151209"],"URL":"https:\/\/doi.org\/10.1002\/pd.1970151209","archive":["Portico"],"relation":{},"ISSN":["0197-3851","1097-0223"],"issn-type":[{"value":"0197-3851","type":"print"},{"value":"1097-0223","type":"electronic"}],"subject":[],"published":{"date-parts":[[1995,12]]}}}