definately not. especially if you were close to them before the relationship. a lot of people make that mistake. if you & your new partner have a good relationship with trust and communication, they should understand the prior freidnship. granted, you may have to tone it down a bit with your friends, ie. not doing as much together as before or anything that may make your new partner feel threatened. but in general, we need our opposite sex friends when we are in a relationship for advice on how the other sex thinks, etc. it's great to get a point of view from the opposite sex sometimes. as long as your friend of the opposite sex isn't bent on sabbatoging your current relationship, i'd say keep them as a friend.
bottom line: It's NEVER good to cut off any friends (male or female) just for the sake of a new relationship! b/c if & when that relationship ends, your former friends will not want to speak to you anymore & will see you as a shallow person who gives up their friendships to please their partner. if your new partner is too jealous to accept your platonic friendships & you aren't doing anything disrespectful to your partner (ie. spending too much time w/friend, talking for hours on phone, putting your friend b/f your relationship) then i think you need to evaluate how jealous your partner is & if you have to cut off friends to be with them, it's not a healthy relationship.