Muscles around the vaginal opening, also called Pelvic Floor Muscles, have ability to even to grip a finger firmly when it is inserted inside the vagina.
Hence, size of the penis does not matter if woman is interested in enjoying mutually gratifying sexual intercourse.
The outer third of the vagina measuring about 1.5 to 2 inches especially the front wall of vagina is most sensitive for woman to get sexual pleasure. Hence sufficiently harder penis of any size can give good pleasure to man as well as woman during intercourse.
Woman can get greater pleasure by choosing sexual position for intercourse wherein she can feel pressure of penis on the front wall of vagina. This makes size of the penis insignificant. Hence, intimacy developed with the partner matters more than size of penis, than developing anxiety about size of the penis.
On arousal the length of the vagina also increases pushing the cervix upwards and backwards, thus even the penis of larger size can be accommodated.
During birth of a child through vagina, the vagina expands excessively to accommodate smooth passage of the baby for birth. This may cause loss of elasticity of vaginal muscles and make them weaker which often leads to difficulties in enjoying sex subsequently.
Kegal exercises explained separately, can help in regaining strength of pelvic floor muscles and resuming sexual responsiveness.
The mucosa, the inner lining of vaginal walls produces thick and sticky fluid which keeps the vagina clean and bacteria free. With foreplay when the woman is sexually aroused, this secretion increases to allow lubrication for smooth movements of penis during intercourse.
Sometimes during intercourse, the penis touches the cervix creating a painful experience for woman. This generally happens when woman is not aroused properly before inserting penis, and the vaginal passage is not elongated enough to accommodate movements of penis.
However, in some women even after sufficient arousal and elongation of vaginal passage, the penis touches the opening of uterus i.e. cervix. This happens when the penis is of larger size than normal or when man is having very hard erection and is giving deep and violent thrusts in a mood of extreme excitement.
This is a painful situation, wherein woman usually suffers rather than getting pleasure of sexual intercourse. Some women even try to bear with it to avoid disappointment of their partner.
In such situations, women should communicate her partner to be slower and gentler. Woman may also prefer or suggest “woman on Top” position which is more comfortable because woman can actually control the depth, direction and rhythm of insertion during intercourse.