NEW YORK (AP) — There's little doubt: Zika is coming to the continental United States, bringing frightening birth defects — and, most likely, newly urgent discussions about abortion and contraception.
Fearful they might bear children who suffer from brain-damaging birth defects caused by Zika, more women are expected to look for ways to prevent or end pregnancies. But the highest risk of Zika spreading is in Southern states where long-lasting birth control and abortions are harder to procure, and where a mosquito that transmits the virus already is plentiful.
"I think it's really important, facing this potential for Zika transmission in the U.S., to be thoughtful and prepared to have straightforward conversations about reproductive health services," said Dr. Christine Curry, a University of Miami obstetrician who has been treating women concerned about Zika infection.
The issues already have been raised in Latin America, epicenter of the Zika epidemic and home to numerous countries where abortion is illegal.
Zika is mainly spread by Aedes aegypti mosquitoes, but that kind of transmission has not yet been seen in the U.S. mainland. Most of the 472 reported infections in the 50 states have been seen in people who traveled to — and were infected in — Zika outbreak countries. Mosquitoes have already been spreading the virus in Puerto Rico and two other subtropical U.S. territories.
Experts think that will happen elsewhere in the U.S. in the months ahead, when hot weather hits and mosquito populations boom.
It would be the first time the nation faced a mosquito-borne germ that causes birth defects. But some experts said a chapter in U.S. history from the mid-20th century may offer some lessons.
It involved rubella — also known as German measles, a disease spread not by mosquitoes but by people. Like Zika, rubella was long thought to cause only mild disease, but became a menace when doctors linked rubella infections in pregnant women to terrible birth defects. As is the case with Zika, it took years to develop a vaccine against rubella, and families were faced with hard decisions in the interim.
In the early 1960s, a huge rubella epidemic infected more than 12 million Americans. Thousands of babies born to infected moms died soon after birth, and doctors calculated that 85 percent of women infected with rubella early in their pregnancy would have babies severely harmed by the virus.
"Most women, with that information, chose to end their pregnancy," said Dr. Paul Offit, a vaccine researcher and medical historian. Indeed, 5,000 infected women had abortions during that epidemic, he said.
Experts don't expect Zika to sweep the U.S. mainland the way it spread through some Latin American and Caribbean countries. A colder climate limits the range of Aedes aegypti, and the greater use of air conditioning and window screens will probably lessen its impact even in the Southern states where transmission is most likely.
A second, more cold-hardy mosquito — the Aedes albopictus, or "Asian tiger" — is also capable of spreading Zika and is more widespread across the United States. But experts have considered the Asian tiger less of a threat to spark outbreaks than the Aedes aegypti.
So the betting money is on clusters of cases limited to a few states — most likely Florida, Texas or Hawaii. That would be a small impact compared with the nationwide rubella epidemic.
And it's not yet clear that a Zika infection during pregnancy will be as likely to mean death or severe damage for the fetus as rubella did.
"That's one of the most important questions for us to answer" right now, said the CDC's Dr. Anne Schuchat at a White House briefing last month.
A couple of small, early reviews of cases in other countries suggest that somewhere between 1 and 29 percent of women infected with Zika during pregnancy might have fetuses or babies with birth defects.
If the risk is 1 percent, a pregnant woman may well want to carry through the pregnancy, Offit said. As the risk gets larger, at some point more women may think about abortion, he said.
Complicating their decision: Even in cases when women are infected early in their pregnancy, ultrasound exams of fetuses have not shown signs of Zika-related birth defects until after 20 weeks — a point at which destruction of the fetus would be considered a "late-term abortion."
Late-term abortions are more expensive, can be riskier for the mother, and involve a more developed fetus. About 20 states prohibit abortions past a certain number of weeks, in some cases making exceptions to save the life or health of the woman. In 12 of the states, the prohibitions kick in at 20 to 22 weeks.
Serious birth defects "may not be picked up until well after the termination cut-off in a specific state. Termination may not be an option for these women," said Dr. Jeanne Sheffield, a Johns Hopkins University obstetrician who has advised the CDC on Zika-related pregnancy issues.
The specter of any Zika-driven abortions is alarming, said the Rev. Frank Pavone, National Director of Priests for Life.
"Naturally the Zika virus is a cause for concern, and we call upon governments and medical professionals to continue to develop appropriate treatments and interventions," Pavone said, in a prepared statement.
"But in no way does this justify recourse to abortion. The child in the womb is a patient too, and killing one's patient is never an appropriate response," he said.
Though the U.S. Supreme Court famously ruled abortion is legal in 1973, the last decade has seen state legislatures pass a wave of abortion limitations and restrictions, including when during a pregnancy abortions can be done and what techniques can be used. The number of clinics, hospitals and doctors' offices that perform abortions has been shrinking, with notable declines in some of the states most likely to see Zika outbreaks.
A closely related topic is access to birth control, because nearly half of women who have abortions were not using contraception.
Condoms are often discussed because — when used effectively — they are a barrier to the Zika virus being spread to a woman through semen. But they are less than perfect at preventing pregnancy. Over one year, the probability of having an unintended pregnancy for a couple that uses only condoms is 17 percent, according to the CDC. It drops to 9 percent for couples that rely on the pill, to 7 percent for injections like Depo-Provera, and to less than 1 percent for implants and IUDs.
For a couple trying to avoid pregnancy during a lasting Zika outbreak, "I would not recommend a condom exclusively," said Carol Hogue, an Emory University expert on birth trends.
The Affordable Care Act covers contraception, and experts believe it's helped more working women get birth control. State Medicaid programs cover at least some forms of birth control, too. But not every method of birth control is always available, experts say.
In fact, there are no good estimates of how many U.S. women need contraception — particularly the more effective types of contraception — and can't get it, said Adam Sonfield, a Guttmacher Institute researcher.
There has been a push in some states to keep contraception funding away from groups that might refer women to abortion clinics.
In 2013, the Texas legislature cut Planned Parenthood from the program that funds birth control and other family planning services for low-income women. In a medical journal article published this year, researchers looked at the effect of that change. They reported significant declines in women using long-acting forms of birth control, and a significant increase in births to low-income women.
Florida's legislature recently adopted a similar measure, cutting Planned Parenthood clinics out of Medicaid funding.
Nearly half of U.S. pregnancies are unintended, meaning a couple failed to properly use effective forms of contraception. In Texas, it's more than half. And in Florida, it's nearly 60 percent, according to Guttmacher estimates from 2010.
The national figure "indicates to me there is a large unmet need for contraception in the United States, and that we need to look for ways to make contraception more available for women who want it," said Dr. Denise Jamieson, leader of a CDC team looking at Zika and unintended pregnancy.
The CDC is recommending that when a woman is pregnant, a couple should abstain from sex or use condoms during the entire pregnancy if the man may have been infected with Zika.
More recently, the CDC said couples who are trying to conceive should always use condoms or abstain from sex for six months if the man had confirmed illness or Zika symptoms and was in an outbreak area.
CDC officials have declined to discuss the issue of abortion services. Nor have they followed the lead of some officials in Latin America who have advised women to postpone starting families until a threat of local infection subsides.