I am against this. There are so many problems with this and really no benefit to it.
We have young adults who are starting to use Plan B as primary birth control. Teenagers are even more likely to do this. (I personally know someone who used Plan B as her primary form of birth control, couldn't afford it in time and got pregnant.)
Plus, teens are the responsibility of their parents. Their health is their parents' concern til they are out on their own. Plus, parents are more likely to know about possible problems that could come up with conditions a teen may have than the teen themselves, especially when it comes to some of the disorders/diseases that aren't really a big deal except when it comes to adding certain hormones to your body (I have one of those, why I'm limited on what BC I can use). Teens don't think about all these things, parents are more likely to think of these things.
I have no issue with Plan B, nor even with teenagers having sex. I think teens should be encouraged and taught safe sexual practices. Allowing easy access to this pill means that teens, who are notoriously lazy, irresponsible, and/or concerned about disappointing their parents are likely to be prone to use Plan B as primary birth control rather than the emergency birth control it is meant to be.
Evidence of misuse being common of Plan B.
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The women who use the morning after pill as everyday contraception | Mail Online