Palin's *teenage* daughter wasn't blamed for anything and nobody said she had a problem (though obviously she does in a sense, what with the shotgun wedding).
Read this carefully:
The fact that Bristol Palin got pregnant at the age of 17 was relevant because Sarah Palin has been promoting abstinence-only sex education and still does. It is proven that abstinence-only sex education does not work and leaves people ignorant and vulnerable if they do decide to have sex (ignorant about contraceptives and ignorant about STDs). Nobody had a problem with Bristol, but the fact that Palin *still* didn't see that there is a problem with abstinence-only programs seeing as it didn't work for *her own daughter* was.

Hope you finally got that. The reason no-one is making an issue out of Ms Sanchez' pregnancy is that she is not 17 and relying to another's ideas of sex education to protect herself. A (presumably) informed adult woman getting pregnant is not the same as a 17 year old getting pregnant, presumably because she was uninformed thanks to her ignorant mother… who was about to treat the rest of the US to the same brand of ignorance.

And as a side note, nobody gives or gave a flying bleep about whether or not Bristol Palin was married. Marriage was not the issue (and "out of wedlock" shouldn't be an issue in the 21st century to begin with).