# cervical mucus plays a key role in the female reproductive cycle - plays a key role in the female reproductive cycle - helps to fertilize the egg and transports sperm to the fallopian tube - cervical mucus helps to nourish sperm - provide a medium for motility - and provide a defense against foreign bodies > Studies (Odeblad et al. 1984) showed that S mucus was very fluid (Figure 5) and that sperm cells moved along the canal very rapidly in S mucus, reaching the S crypts in 3-10 minutes. L mucus had a medium viscosity. Unit structures of L mucus attracted malformed sperm cells or those which moved slowly, and this "filtration" of sperm cells is efficacious (Odeblad 1985).[[(Odeblad, 1994)#^0u-pl]]