Mannose-binding lectin genotypes: potential role in tubal damage and adverse IVF outcome

The innate immune system provides the first-line defence against genital tract pathogens and is also involved in establishing and maintaining a successful pregnancy. Genetic variation of factors regulating immune response can be associated with complications after genital tract infections and may lead to unfavourable pregnancy outcomes. This study focused on four polymorphisms in the mannose binding lectin gene (MBL2) and assessed their significance in tubal damage and female fertility by comparing genotype frequencies among 388 controls and women with tubal factor infertility (n = 155) or previous ectopic pregnancy (n = 178). The high-producing MBL2 genotype HYA/LYA was found to have a protective effect, while the hyper-producing MBL2 genotype HYA/HYA and low-producing MBL2 genotypes were associated with susceptibility to tubal factor infertility. Also, the low-producing genotypes showed association with early pregnancy loss in IVF treatment. In conclusion, these data suggest that certain MBL2 genotypes can be associated with tubal damage in patients with evidence of Chlamydia trachomatis infection and additionally may contribute to the pathogenesis of early pregnancy loss.