How is the term "anti-choice" more dishonest than the term "pro-abortion"?
Consider attitudes toward slavery in the US 150 years ago. Not everyone who was pro-slavery actually owned slaves, or even wanted to. There were many in the South, and more than a few in the North, who personally objected to slave-owning but thought it should not be made illegal. Some thought that the African slaves were so obviously inferior -- according to their ideas, perhaps not even fully human -- that they could not function in "higher" society without being controlled. In the minds of such people, the choice was either to control the Africans through ownership (i.e. slavery) or ship them all "back to Africa," conveniently ignoring the fact that almost all slaves at the time had been born in America. Others thought owning a slave was morally abhorrent, but believed that each state needed to be able to make that call for itself rather than concentrating such sweeping power into a centralized federal government. They may have disapproved of slavery, but they saw the question as a matter (ironically enough) of freedom.
(Note the stunning parallels of both types of thinking with modern thinking about abortion, both those who call the baby a mere "mass of cells," undeserving of protection, and those who go with the "I-wouldn't-abort-but-I-can't-make-that-decision-for-others" line.)
In any case, I expect you would agree that calling all such people "pro-slavery" would not be a misrepresentation of their position. "Pro-slavery" didn't necessarily mean you wanted to own a slave, or that every single person of African descent should be a slave. It did not even mean you liked slavery
per se. Rather, it meant that you believed that the institution of slavery should be allowed to exist.
Similarly, calling someone "pro-abortion" doesn't mean they want every pregnancy to be terminated in elective abortion; rather, it means the pro-abortionist supports the existence and availability of the institution of elective abortion.
On the other hand, "anti-choice" is a completely bogus term. Those who do not support elective abortion on demand believe that every woman (and man) should be allowed to choose whether or not to engage in sexual relations. In fact, the majority of the pro-life movement supports the option to abort in cases of forcible rape, as well as other conditions. Pro-life people are no more against "choice" than abolitionists were against "choice". The "anti-slavery-choice" "pro-abolitionists" simply argued that the "choice" to condemn a man to slavery for selfish (or no) reasons is no choice at all, but moral corruption -- just as the "pro-life" people argue that the "choice" to kill a human baby for convenience's sake is no choice at all, but butchery.
People who are anti-abortion want to change the law so that women have to carry every pregnancy to term.
This is simply false. Very few pro-life supporters believe this. The vast majority see reasonable cause for abortion, and seek only to eliminate elective abortion of convenience, the so-called "contraceptive abortion". Your statement is a blatant mischaracterization developed by the pro-abortion-rights crowd, which I can only hope you are unwittingly passing on because you haven't thought it through yet. In any case, it is untrue.
People who are pro-choice want to uphold current law, which gives pregnant women the ability to choose whether or not to carry their pregnancies to term.
When the "current law" is appallingly evil, as for example slavery in the 1850s, citing it as "upholding current law" isn't a convincing moral argument. Pro-lifers argue that the women had the choice at conception whether or not to engage in acts that could lead to pregnancy. Seeking to avoid responsibility for a choice you made is not sufficient justification for killing a baby.
If you believe in the "right" to kill a preborn baby at any time for any reason, you will have difficulty rationally arguing that the same standard should not apply to post-born babies. The difference is not of type, but purely of degree.