Depends on who you ask. The definition below pretty much says that any woman who has sex after drinking was raped, because her judgement was impaired.
http://www.care.uci.edu/general/Sexual-Assault---Defining.aspx
Rape: A specific form of sexual assault that includes an act of sexual intercourse (vaginal, anal, or oral penetration), accomplished against a person who does not consent to the sexual contact, or is incapable of consenting. This includes situations in which a victim is...
Forced to engage in intercourse
Threatened with harm if they do not participate
Prevented from resisting due to intoxication from alcohol or drugs
Incapable of giving consent because of a disability
Asleep or unconscious to the nature of the act
...
Alcohol is the most commonly used chemical in drug facilitated sexual assault. In large part this is due to the fact that alcohol is easily accessible and a chemical that many people use in social interactions.
Effects on the Victim:
Ability to protect herself or himself is reduced
Impaired judgment
May not realize that a situation has become dangerous
May have trouble handling or avoiding conflict
Perceptions of others not as clear
Difficult to set limits
Ability to resist, both physically and verbally, may be impaired