Meanwhile, shallow penetration is supposed to boost your chances of having a girl, because according to Shettles X-carrying sperm are more robust, and therefore survive longer in the
harsh vaginal environment.
But as estrogen levels rise and drop, the
whole vaginal environment changes, and — really, I can't describe it nearly as well as you can interpret it as you feel it yourself — you can really sense the difference in your cervix.
The decrease in Lactobacillus and increase in G. vaginalis leads to a rise in the vagina's pH. The
new vaginal environment is less acidic and more alkaline; a vaginal pH of more than 4.5 is one criterion for the diagnosis of bacterial vaginosis.
Dr. Marc Baum, the lead scientist at Oak Crest and co-author of the work, stated «this model is unique as it faithfully recreates
the vaginal environment ex vivo, both in terms of the host cellular physiology and the associated complex vaginal microbiomes that could not previously be cultured.
The technical term is bacterial vaginosis, and it can be triggered by anything that makes
the vaginal environment less acidic, including semen, menstrual blood and douches.
Additionally, cups don't absorb the natural moisture of
the vaginal environment, thereby helping to maintain healthy pH levels, which result in healthier intimate flora (sayonara yeast infections and BV!).