Of all clinically recognized pregnancies, about 15% end in loss (Nybo Andersen et al., 2000; Rai and Regan, 2006). The great majority of pregnancy losses occur within the first trimester of pregnancy (Baird, 2009; Farr et al., 2007). Aneuploidy of the embryo is an important female age-related genetic cause of pregnancy loss and can be tested in pregnancy loss tissue (Hassold and Hunt, 2001; Rai and Regan, 2006). A proportion of couples (1–3%) not only suffer from one ‘sporadic’ pregnancy loss but from recurrent pregnancy loss, meaning two or more pregnancy losses (historically three or more losses) (Ford and Schust, 2009).