Maternal serum free beta-hCG and PAPP-A in patients with habitual abortion-influence on first-trimester screening for chromosomal abnormalities

Abstract

Objective: To explore if maternal serum free beta-hCG and pregnancy-associated plasma protein A (PAPP-A) levels in the first-trimester of pregnancy are altered in patients with habitual abortions and if there is an effect on first-trimester screening for Down syndrome.

Methods: A retrospective study was conducted on 913 normal singleton fetuses that underwent first-trimester combined screening for Down syndrome. Maternal serum PAPP-A and free beta-hCG were compared between patients with (n = 64) and without habitual abortions (n = 849).

Results: The medians +/- SD log(10) MoM of PAPP-A and free beta-hCG +/- SD in patients with and without habitual abortions were 0.063 +/- 0.28 versus - 0.014 +/- 0.27 and - 0.001 +/- 0.27 versus - 0.018 +/- 0.31, with a p value of 0.042 and 0.87, respectively. The screen positive rate setting the cut off at 1:350 looking at the background risk for trisomy 21 was 71.4% in women with and 81.2% in women without habitual abortion, after combined first-trimester screening it was 7.8% in women with and 10.1% in women without recurrent abortion.

Conclusions: Patients with habitual abortions have slightly increased maternal serum PAPP-A levels in the first-trimester. This marginal difference seems not to effect risk calculation in combined first-trimester screening for trisomy 21.