Zestica™ Fertility contains the natural ingredient Hyaluronic Acid (HA) with a combination of different molecular weights to sustain its stability in the vaginal acidic environment.
HA is a super-water absorbent with natural moisturisation functionality which makes it a fantastic lubricant with a well proven safety profile.
The Role of Hyaluronic Acid in Reproduction (HA in cervical mucus and its interaction with sperm)
The composition and characteristics of cervical mucus change considerably throughout the menstrual cycle (and during pregnancy). Cervical mucus is only receptive to sperm up to 6 days prior to, and approximately 1 day following, ovulation. During the rest of the menstrual cycle cervical mucus is “hostile” to sperm i.e. sperm are unable to penetrate.
The ejaculate consists of spermatozoa and seminal plasma with sperm comprising only 5% of the ejaculate. The seminal plasma contains a myriad of factors which act to provide the sperm with energy and protection while in the vagina. In humans, sperm are thought to enter the cervix via cervical mucus relatively quickly after ejaculation (within 1 hour). Sperm that remain in the vagina for a long time will die and in order to survive, and progress to the egg, they need to swim and enter the cervical mucus which acts as a comparative haven. Upon entering cervical mucus, they are stripped of their outer coat (which acts to keep them in a suppressed non fertile state) and thus undergo the first stage of activation (termed capacitation). It is unknown how long sperm remain in the cervix in an active state, yet still remain capable of fertilization, but studies in the laboratory would indicate this can be several days.
The concentration of hyaluronic acid (HA) in the cervix changes throughout pregnancy, and in particular increases during the latter stages of pregnancy where it is thought to play a significant role in cervical ripening (remodelling of the cervix in preparation for birth).
The role of HA in cervical mucus and its subsequent effect on sperm is not well understood. However, HA has been used as a cervical mucus substitute for laboratory sperm function studies for the last 25 years. As such, there is a wealth of information regarding the interaction of HA with sperm. HA has been used as a cervical mucus substitute because its structure and properties are similar. The penetration of sperm into HA is highly correlated with semen characteristics and sperm function testing – to the same degree as with cervical mucus. Additionally, the functional capacity of sperm that have penetrated HA or cervical mucus (motility, capacitation status, fertilizing ability) are very similar. Therefore penetration into HA is regarded as a simple and objective means of measuring the functional competence of sperm and is widely used as an effective alternative to human cervical mucus.
HA in the Oviduct
Sperm are stored, sometimes for several days, in the oviduct prior to fertilization. The oviduct acts to maintain sperm in a quiescent but “always primed” state of readiness for the arrival of the egg. How the oviduct does this is unknown but glycosaminoglycans, like HA, play a key role in these processes. Importantly, these glycosaminoglycans, in conjunction with other factors in the oviduct (for example, binding to the oviductal epithelium), act as a final gatekeeper to prepare the sperm by activating key signalling complexes in the sperm so that they are ready to interact with the egg. However, because sperm can remain in the oviduct for several days the oviduct needs to achieve an important balance in not over-stimulating the sperm, otherwise they would not be able to fertilize eggs.