Stability of free beta-hCG in the routine screening of Down syndrome in the first trimester of pregnancy.
Stability of free beta-human chorionic gonadotropin in maternal blood upon storage at ambient and refrigerator temperatures as well as stability under conditions simulating postal transport were studied. A group of 26 women in the first trimester of pregnancy were included in the study, blood samples were taken during the routine check-up. Blood samples were aliquoted stored in different conditions that should mimic the transportation and then analysed for free beta-hCG. No significant differences were found in the free beta-hCG levels in samples after 24 and 48 hours resp., stored in refrigerator (2-8 degrees C) without separation. In samples stored in laboratory temperature without separation the average concentration increased from 11 to 20%. Six blood samples were stored at 35 degrees C for 5 hours and then in laboratory temperature. In this group the average increase of results was from 14.3% to 132.2%. Separation of the sera for Down syndrome screening in 4 hours after withdrawal is necessary. Cooling during any storage, including transportation is highly recommended as the preanalytical phase has a high impact for the analysis.
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Charles University in Prague, First Faculty of Medicine and General Teaching Hospital, Institute of Clinical Biochemistry and Laboratory Diagnostics, Prague, Czech Republic. springer@vfn.cz
Zima
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Arnostová
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D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011296:Prenatal Diagnosis
D018997:Chorionic Gonadotropin, beta Subunit, Human