Increased mRNA expression of vascular endothelial growth factor and its receptor (flt-1) in the hydrosalpinx

Background: The adverse effects of hydrosalpinx on the outcomes of IVF have been well documented, but the mechanisms of hydrosalpinx fluid formation remain unclear. This study compares the mRNA expression of vascular endothelial growth factor (VEGF) and its receptors (KDR and flt-1) in the hydrosalpinx with that in the healthy oviduct. Methods: Oviduct tissue was collected from 10 infertile women with hydrosalpinx and 10 parous women with healthy oviduct. The mRNA expression of VEGF and its receptors in isolated oviduct epithelial cells were analysed using semi-quantitative reverse-transcriptase PCR. Results: mRNA expression of VEGF and its receptor flt-1 in the hydrosalpinx was significantly higher than that in the healthy oviduct, but no significant difference was demonstrated for the KDR receptor. Conclusions: This study supports the notion that VEGF may play an important role in the hydrosalpinx fluid formation, possibly by promoting vascular and epithelial permeability and therefore serum transudation.