Sperm toxicity testing on lubricant gels: should we be recommending 'fertility-friendly' specialist products?

Abstract

Couples trying to conceive or providing samples for Assisted Reproductive Technologies (ART) are advised against the use of lubricant-gels due to the risk of sperm-toxicity. However, gels now exist which are specifically formulated to help couples conceive but without consensus on their toxicity relative to non-specialist products. This study tested gels recently introduced as 'sperm friendly' (FertilSafe Plus, Fertile Check) alongside established lubricants intended for pleasure only using a recently published toxicity testing regime. Computer Assisted Sperm Analysis (CASA) was performed at 1 and 2 h on donor sperm (n = 12) pre-incubated with each gel (10% v/v) and controls. All gels led to a significant loss of motility/velocity at 1 and 2 h (p < 0.01), with the most significant loss from the 2 Durex pleasure products (11% and 15%, vs 47% progression) at 60 min, although these performed better than saliva (used as negative control). Incubation with FertilSafePlus led to the smallest loss of motility (24% vs 47%) at 1 h. Saliva and products designed for lubrication only exhibited the most negative effect on motility and those marketed as 'sperm safe' could be considered the best performers. Whether these affects are due to direct toxicity or are indirect due to other factors such as viscosity, pH or osmolality remains uncertain.