HLA determination in women with RPL is not recommended in clinical practice. Only HLA class II determination (HLA-DRB1*15:01 and HLA-DQB1*05:01/05:2) could be considered in Scandinavian women with secondary RPL after the birth of a boy, for prognostic purposes (Nielsen et al., 2009).	Conditional ⊕⊕○○
Measurement of anti-HY antibodies in women with RPL is not recommended in clinical practice (Nielsen et al., 2010).	Conditional ⊕⊕○○
Cytokine testing should not be used in women with RPL in clinical practice (Mueller-Eckhardt et al., 1994; Calleja-Agius et al., 2012; Lee et al., 2013).	Strong ⊕⊕○○
Cytokine polymorphisms should not be tested in women with RPL (Choi and Kwak-Kim, 2008; Medica et al., 2009).	Strong ⊕⊕⊕○
Antinuclear antibodies (ANA) testing could be considered for explanatory purposes (Christiansen, 1996; Ogasawara et al., 1996; Stern et al., 1998; Kaider et al., 1999; Matsubayashi et al., 2001; Bustos et al., 2006; Giasuddin et al., 2010; Ticconi et al., 2010; Cavalcante et al., 2014; Molazadeh et al., 2014; Hefler-Frischmuth et al., 2017).	Conditional ⊕⊕○○
There is insufficient evidence to recommend natural killer (NK) cell testing of either peripheral blood or endometrial tissue in women with RPL (Chao et al., 1995, Souza et al., 2002, Shakhar et al., 2006; Hadinedoushan et al., 2007, Karami et al., 2012, Lee et al., 2013).	Strong ⊕○○○
Testing anti-HLA antibodies in women with RPL is not recommended (Lashley et al., 2013).	Strong ⊕⊕⊕○