It is a round artificial sponge with spermacide which a woman can insert in her vagina ...is her ghusl invalidated upon removal of the sponge?

I live in the United States and there is a contraceptive method which is being introduced here which I would like to inquire about. It isa round artificial sponge with spermacide which a woman can insert in her vagina prior to intercourse and it can remain there for 24 hours. The function of this sponge is to act as a barrier and an absorbant for the semen. My questions are as follows: If a woman uses this sponge and takes a ghusl after intercourse without removing the sponge, is the ghusl valid? Can she make salaat, read quraan, etc. while the sponge is still in its place inside her? If her ghusl is valid and she removes the sponge after a few hours of taking the ghusl, is her ghusl invalidated upon removal of the sponge? Also, what about fasting? If ahe makes the intention to fast while the sponge is still in its place, is her fasting impacted? What if she removes the sponge while fasting, does that invalidate her fast? If the 'mani' of the woman is blocked by this sponge and ahe takes a ghusl and then after a few hours removes the sponge, will her ghusl be invalidated when her 'mani' comes out?