The WPATH SOC version 6 and 7 allow for referral for puberty blocking medication to be prescribed to youth experiencing puberty, starting at Tanner stage 2 or above. Referral after that age could lead to bodily changes reversible only with surgery (facial shape, secondary sex characteristics); surgically risky (voice pitch); or, irreversible changes (skeletal structure or height). The WPATH SOC version 7 has also removed the set length of time for psychotherapy, in order to facilitate support and referral to transition services in a timely way, should they be required. These changes have led some critics to claim that the criteria are too loose, however, an individualized approach that provides prospective, supportive follow-up and education to families about how to affirm expression, and create an environment for safe exploration has always been recommended.