To repeat: high vaginal readings = high progesterone levels = low fertility. (ovagraph.com)
You need higher progesterone levels to sustain a pregnancy. (health.com)
When saliva was alternatively used to measure sex hormones, Frydenberg and colleagues found that high mammographic density was significantly associated with high progesterone levels among women ages 25 to 35 years old (32). (cebp.aacrjournals.org)