A judge has given the okay to Arizona's new abortion ban, causing abortion rights groups to announce their plan to appeal.

FOX News Radio's Lisa Lacerra has more on the new law:

The ban, set to take effect Thursday, prohibits abortions starting at 20 weeks of pregnancy, except in medical emergencies.  The current ban is at viability, or when the fetus could survive outside the womb - at about 24 weeks.

The judge, saying the statute may prompt a few pregnant women who are considering abortion to make the decision earlier, but says the law is Constitutional because it doesn't prohibit women from making the decision to end their pregnancies.

Arizona is one of 10 states to enact types of 20-week bans.

Lisa Lacerra, FOX News Radio.