1. Additive effect of factors related to assisted conception on the reduction of maternal serum pregnancy-associated plasma protein A concentrations and the increased false- positive rates in first-trimester Down syndrome screening 
José Bellver, M.D., Cristina Casanova, M.D., Nicolás Garrido, Ph.D., Coral Lara, M.D., José Remohí, M.D., Antonio Pellicer, M.D., Vicente Serra, M.D. 
Fertility and Sterility 
Volume 100, Issue 5, Pages e3 (November 2013)
DOI: /j.fertnstert
Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions

2. Figure 1 Sample size according to the mode of conception.
Fertility and Sterility  , e3DOI: ( /j.fertnstert )
Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions

3. Figure 2
Comparison of PAPP-A, fβ-hCG, and NT MoM values in singleton pregnancies between natural conceptions and those achieved with different modes of assisted reproduction using fresh embryos. *P<.05 in MoM values with respect to natural conceptions; ¥P<.05 in FPRs with respect to natural conceptions.
Fertility and Sterility  , e3DOI: ( /j.fertnstert )
Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions

4. Supplemental Figure 1
Trends in maternal PAPP-A serum concentrations and FPRs according to the mode of conception. Frozen: frozen IVF and ICSI cycles.
Fertility and Sterility  , e3DOI: ( /j.fertnstert )
Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions