In the past, some hospitals have denied gay and lesbian partners the same rights as heterosexual spouses. They have been refused visitation rights when their partner is sick, and they have not been allowed to make critical health decisions for their partner, despite having been designated as the person with this responsibility by their partner. That is now set to change, as Obama has decreed that any hospital receiving Medicare or Medicaid funding (the majority of US hospitals) can no longer discriminate against same-sex couples in this way. You can read more here.