The current law, passed in 1967, permitted abortion only until a fetus was "viable", which was assumed to be at 28 weeks.

现行的相关法律颁布于1967年，规定只有在胎儿能成型存活，相当于28周孕期以后才可以终止妊娠。

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Wade and successive Supreme Court decisions that established states couldn't ban abortions carried out before a fetus becomes viable, or able to survive outside the womb.

WSJ: States Harden Views Over Laws Governing Abortion