Feasibility of rapid prenatal diagnosis in advanced maternal age women

Abstract

Objective To analyze the feasibility of rapid prenatal diagnosis in the advanced maternal age women with or without positive serologic screening results.Methods We conducted a retrospective study of the women who underwent a mid-trimester amniocentesis in Peking University First Hospital from January 1,2001 to December 31,2012.Maternal age,indication for invasive prenatal diagnosis,karyotyping and pregnancy outcome were documented.Using a young population with high risk in serologic screening (S) as the standard,chromosome abnormalities in the advanced maternal age (A) group and the advanced maternal age with high risk in serologic screening (A+S) group were compared with the S group.Chromosome abnormalities were divided into detectable (D) and undetectable (U) during rapid prenatal diagnosis.Results Of 9 606 cases,222 (2.3％,222/9 606) cases with chromosome abnormalities were detected,23.0％ (51/222) of which were undetectable by rapid prenatal diagnosis.The detection rate of detectable chromosome abnormalities was 1.8％ (57/3 177) in group A,1.4％(13/925) in group A+S,and 1.8％(57/3 250) in group S (x2=0.662,P＞0.05).The rate of undetectable chromosome abnormalities was 0.5％ (15/3 177) in group A,0.3％ (3/925) in group A+S,and 0.5％ (16/3 250) in group S (x2=0.452,P＞0.05).The most common indications for undetectable chromosome abnormalities in the young population were abnormal history of pregnancy,abnormal family history and chromosome abnormality history (16.4％,9/55),and abnormal ultrasound in the advanced maternal age population (4.4％,3/68).Conclusions The performance of rapid prenatal diagnosis in the advanced maternal age population with or without high risk in screening without abnormal findings in ultrasound,was similar to the young population with high risk in screening.Fluorescent in situ hybridization may be integrated into the strategy of prenatal diagnosis for this group of women. Key words: Prenatal diagnosis; Amniocentesis; Karyotyping; In situ hybridization, fluorescence; Pregnancy trimester, second