In essence the answer should be yes. I can see three main exceptions:

1. there is a limit where the rights of others are affected
2. there must be certainty that whatever the person has decided is based on a free choice, not unduly affected by internal or external agents.
3. as for the mother with child: A mother can decide for herself, not for the unborn individual within her. That is a separate person and she has limited rights to decide for that individual.