1. Impact of blastocyst transfer on offspring sex ratio and the monozygotic twinning rate: a systematic review and meta-analysis 
Hye Jin Chang, M.D., Ph.D., Jung Ryeol Lee, M.D., Byung Chul Jee, M.D., Ph.D., Chang Suk Suh, M.D., Ph.D., Seok Hyun Kim, M.D., Ph.D. 
Fertility and Sterility 
Volume 91, Issue 6, Pages (June 2009)
DOI: /j.fertnstert
Copyright © 2009 American Society for Reproductive Medicine Terms and Conditions

2. Figure 1
Sex ratio in infants born after blastocyst versus cleavage-stage embryo transfers. CI = confidence interval; OR = odds ratio.
Fertility and Sterility  , DOI: ( /j.fertnstert )
Copyright © 2009 American Society for Reproductive Medicine Terms and Conditions

3. Figure 2
Monozygotic twinning rates per pregnancy using random effect model. Abbreviations as in Figure 1.
Fertility and Sterility  , DOI: ( /j.fertnstert )
Copyright © 2009 American Society for Reproductive Medicine Terms and Conditions

4. Figure 3
Monozygotic twinning rates per pregnancy (grouped by period of study performed) using fixed effect model. Abbreviations as in Figure 1.
Fertility and Sterility  , DOI: ( /j.fertnstert )
Copyright © 2009 American Society for Reproductive Medicine Terms and Conditions