No. The diaphragm fits into the deep portion of the vagina where there are hardly any nerve endings. Real stimulation is in the outer aspect i.e. clitoris and the surrounding area and the outer one-third of the vagina. The diaphragm in no way inhibits a woman’s orgasm.

It is not necessary that a woman should reach orgasm during intercourse. She may achieve orgasm during foreplay or after play by any method including clitoral stimulation. What is important is satisfaction, no matter how one derives it.