Many women are not aware that most sexual lubricants can impair their fertility . Obviously, your standard lubricant is not a “spermicide” in the truest sense of the word and should never be used to try to prevent a pregnancy, but for couples struggling to achieve a pregnancy it can make a difference in their ability to conceive. This is because most lubricants are intended to not disrupt the natural conditions of the vagina.
The vagina normally has a pH of 3.8 to 4.2, anything over a pH of 4.5 can indicate a vaginal infection. This acidic pH is maintained by healthy bacteria that live in the vagina and produce acidic secretions. When the vagina has a low, or acidic, pH it is less susceptible to developing an infection. Being that this acidic condition is normal when a woman is healthy, many spermicides have pH’s that are acidic to more closely match the woman’s own body. Which brings us to our first point about lubricants and fertility. Seminal fluid has a pH of about 8.1, it is very basic and sperm cannot survive in acidic conditions. At the time of fertility the woman’s cervix begins to produce cervical fluid that has a similar basic pH, allowing for sperm survival only when the woman is fertile. Thus, if a couple was using an acidic sexual lubricant around the time of fertility they would be exposing the sperm to a very acidic solution that could increase the number of sperm killed.
The other factor to consider when looking at lubricants is what they look like on a microscopic level. At the time of fertility the cervix begins to secrete what is know as Type E mucus. This Type E mucus forms little microscopic channels that allow healthy sperm to quickly swim through the cervix, while preventing abnormal sperm from making their way through. Many lubricants do not allow for easy sperm penetration, in other words, the sperm have difficulty swimming through the lubricant.
So what’s a Creighton Model user to do? On days of infertility, use whatever lubricant you prefer, this is also true if you use a small amount of lubricant to help insert tampons, or vaginal medications. Water soluble lubricants are best. For times of fertility, we recommend the use of a sexual lubricant called PreSeed. The characteristics of PreSeed allow for greater sperm survival and sperm penetration through the lubricant. PreSeed can be used with or without an applicator and can be purchased on-line or at some pharmacies.