Aim. The definition of recurrent pregnancy loss (RPL) or recurrent miscarriage (RM) is the loss of two or more pregnancies before 24 weeks of gestation or at any point during pregnancy. The susceptibility to infections can alter the risk of RM/RPL in individuals. Our study utilized a Mendelian Randomisation approach to examine the causal relationship between ten infectious diseases — chickenpox, shingles, mononucleosis, mumps, measles, scarlet fever, bacterial meningitis, hepatitis B, hepatitis A, and COVID-19 — and the subsequent risk of pregnancy loss. Conclusions. Our findings indicate that prior exposure to herpes zoster infections may provide protective effects against idiopathic pregnancy loss.