1. Blood-borne angiogenic factors and sustained multiple implantation: a comparison of singleton and twin pregnancies 
Els Groeneveld, Marieke J. Lambers, Diederik A. Hoozemans, Roel Schats, Peter G.A. Hompes, Cornelis B. Lambalk 
Reproductive BioMedicine Online 
Volume 20, Issue 6, Pages (June 2010)
DOI: /j.rbmo
Copyright © 2010 Reproductive Healthcare Ltd. Terms and Conditions

2. Figure 1
Flowchart of study population. DET=double-embryo transfer; ET=embryo transfer; IC=informed consent; IUI=intrauterine insemination; OHSS=ovarian hyperstimulation syndrome; SET=single-embryo transfer; TFF=total fertilization failure.
Reproductive BioMedicine Online  , DOI: ( /j.rbmo )
Copyright © 2010 Reproductive Healthcare Ltd. Terms and Conditions

3. Figure 2
Serum vascular endothelial growth factor-A concentrations (mean±SD) in maternal serum of 25 patients with ongoing singleton (grey bars; n=16) and twin (black bars; n=9) pregnancies. CD3=cycle day 3 after menstrual bleeding; GA=gestational age; VEGF-A=vascular endothelial growth factor-A. ∗P<0.05.
Reproductive BioMedicine Online  , DOI: ( /j.rbmo )
Copyright © 2010 Reproductive Healthcare Ltd. Terms and Conditions

4. Figure 3
Serum inhibin A concentrations (mean±SD) in maternal serum of 25 patients with ongoing singleton (grey bars; n=16) and twin (black bars; n=9) pregnancies. ET=embryo transfer; GA=gestational age. ∗P<0.05.
Reproductive BioMedicine Online  , DOI: ( /j.rbmo )
Copyright © 2010 Reproductive Healthcare Ltd. Terms and Conditions

5. Figure 4
Glycodelin A concentrations (mean±SD) in maternal serum of 25 patients with ongoing singleton (grey bars; n=16) and twin (black bars; n=9) pregnancies. CD3=cycle day 3 after menstrual bleeding; GA=gestational age.
Reproductive BioMedicine Online  , DOI: ( /j.rbmo )
Copyright © 2010 Reproductive Healthcare Ltd. Terms and Conditions