True. The cul de sac is actually even further - between the bottom vaginal wall and anal canal. I've heard reports that the cul de sac being contacted (by pushing the bottom wall well into it) creates even stronger sensation in some women, but it remains unclear as sometimes people aren't sure what's what and where's where. The posterior fornix is constantly confused with the cul de sac.

Pouch of Douglas definition - Medical Dictionary definitions of popular medical terms easily defined on MedTerms

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