Deadlocks when creating users

Hi,
I'm having this transactio error when my web site is under heavy load.
System.Data.SqlClient.SqlException: Transaction (Process ID 55) was deadlocked on lock resources with another process and has been chosen as the deadlock victim


The method that's doig this is the membership creation:


public static MembershipUser InsertUser(string username, string password, string email, string passwordQuestion, string passwordAnswer, bool isApproved, object providerUserKey, out MembershipCreateStatus membershipCreateStatus)
        {
            using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required))
            {
                MembershipUser membershipUser = Membersh ...