AZ Governor Jan Brewer
© Christopher Halloran / Shutterstock.comJan Brewer
Republican Arizona Gov. Jan Brewer on Thursday signed one of the most controversial and restrictive abortion bans in the country, which experts say effectively bans abortions after 18 weeks and declares that a woman could be pregnant 2 weeks before she even had sex.

"This legislation is consistent with my strong track record of supporting common sense measures to protect the health of women and safeguard our most vulnerable population - the unborn," a statement from the governor's office said.

"Knowing that abortions become riskier the later they are performed in pregnancy, it only makes sense to prohibit these procedures past 20 weeks," Brewer insisted.

Arizona's HB 2036 takes Nebraska's 20-week abortion ban one step further by starting the clock on pregnancies at the woman's last last menstrual period, which could be two weeks before fertilization.

Specifically, the bill would "[p]rohibit abortions at or after twenty weeks of gestation, except in cases of a medical emergency, based on the documented risks to women's health and the strong medical evidence that unborn children feel pain during an abortion at that gestational age," where gestational age is defined as "age of the unborn child as calculated from the first day of the last menstrual period of the pregnant woman."

Guttmacher Institute's State Issues Manager Elizabeth Nash recently told Raw Story that obstetricians start the clock on pregnancies after the "last menstrual period" to "be on the safe side."

"Certainly, they are trying move the gestational cutoff from what had been over the last two years a 20-week gestational cutoff to an 18-week gestational cutoff," Nash explained. "At the same time, they are trying to say, 'Oh, this is a 20-week abortion ban.' And they get away with that with the definition of gestational age that's in the bill."

Even experts who do not disagree with dating pregnancies from the last menstrual period, think that 18 weeks (or 20 weeks gestational age) is far too restrictive.

"Imposing gestational age limits is wrong," Dr. Jennifer Gutner, who is an OB/GYN, recently wrote, referring to a similar bill in Georgia. "There are unfortunate circumstances where lethal or very severe anomalies are not detected until the 3rd trimester. I don't think it's anyone's place to tell a woman who is pregnant with a baby who has no brain and a single eye like a cyclops that she has to go to term."

Planned Parenthood Arizona President Bryan Howard told Reuters that Arizona's new law is the latest in a "harmful" drive by conservatives to curb women's health services.

"We're seeing the hubris overreach in states across the country, not just in the regulation of abortion but in mainstream Planned Parenthood services like birth control and cancer screening," he explained.