We studied 16 SNPs in 12 folate and choline metabolism genes, including BHMT (rs7356530 and rs3733890), BHMT2 (rs625879), CBS (844ins68), CHDH (rs893363 and rs2289205), CHKA (rs7928739), MTHFD1 (rs2236225), MTHFR (rs1801133), MTR (rs1805087), MTRR (rs1801394), PCYT1A (rs712012 and rs7639752), PEMT (rs4244593 and rs4646406) and TCN (rs1801198) in one hundred and sixty-three infertile women with minimal endometriosis and one hundred and fifty fertile women.