Midcycle cervical mucus was obtained from 56 women. Each mucus sample was divided into four portions collected into a capillary tube and kept either at room temperature or at 4°C, ––20°C or in liquid nitrogen for 1 h, afterwards thawed at 37°C and used in the in vitro penetration device for 1 h. 56 semen samples of good quality were used, the same sample for all four types of the same cervical mucus. Very high significant correlations were calculated between the penetration value (PV) rates in all four methods of cervical mucus preservation. Paired t test revealed a significant decrease (p < 0.025) in the PV rates of sperm in the cervical mucus cryopreserved in liquid nitrogen. The results of this study recommend the establishment of a cervical mucus bank using the 4CC and ––20°C as possible methods for preservation of cervical mucus.