RIO DE JANEIRO -- Two Brazilian women, two pregnancies, one nightmare. But two very different stories.

Regina de Lima and Tainara Lourenco became pregnant at a scary moment -- the dawn of an extraordinary Zika outbreak, as authorities came to suspect that the virus was causing an alarming spike in a rare birth defect called microcephaly. Both have reason to fear for the health of their unborn offspring.

But that is where the similarities end.

Lima is well-off, and took advantage of the options of affluence.

Lourenco lives in a slum. She has no options, except to hope for the best.

When Lima learned she was pregnant, her initial, vertiginous rush of happiness was almost immediately smothered by dread.

Lima and her husband had been trying to start a family but decided to put the project on hold in late November, after the Brazilian government announced a possible link between mosquito-borne Zika and microcephaly, in which infants are born with unusually small heads and can sometimes suffer mental retardation or a host of serious health and developmental problems.

The connection between Zika and microcephaly is not yet understood, but the U.S. Centers for Disease Control and Prevention says there is strong evidence of a link. And with more than 3,700 confirmed or suspected cases of microcephaly registered here since October -- compared with fewer than 150 cases in all of 2014 -- the Brazilian government took the drastic step of urging would-be parents to put off pregnancies.

But for Lima, an audiovisual producer from Rio de Janeiro, it was too late. She was already pregnant, and her first trimester -- thought to be when the fetus is most susceptible to Zika -- would coincide with Rio's summer mosquito season.

"The first weeks were terrifying," said Lima. "I cried and cried."

She was haunted by fears she may have already had Zika without knowing it -- the illness can cause a fever and red splotches on the skin, but is asymptomatic in most cases -- and that her baby would develop microcephaly, which ultrasounds only pick up starting in the seventh month.

So Lima did what growing numbers of wealthy Brazilian women are doing: She requested an extended vacation from work, packed her bags and left for Europe. She plans to stay at least through the end of the dicey first trimester.

"I am in a sort of exile -- I could be at home with my husband, seeing my own doctors, but instead I'm here in Europe with a suitcase," Lima said in a telephone interview from London, quickly adding that she wasn't complaining. "I am lucky to have options, to be able to make decisions. Most women in my situation don't have that luxury. They're completely at the mercy of fate."

Indeed, although she's living on a shoestring -- crashing with friends and moving weekly so as not to overstay her welcome -- Lima's peace of mind comes with a price tag that would be unthinkable for the vast majority of women in this most socially stratified of countries.

Her airline ticket alone cost several times the monthly minimum wage of just over $200, and with Brazil's currency at historic lows amid an economic recession, even everyday expenses in Europe have become exorbitant by Brazilian standards.

Unemployed and five months pregnant, 21-year-old Lourenco lives in a slum at the epicenter of Brazil's tandem Zika and microcephaly outbreaks, the state of Pernambuco in Brazil's impoverished and underdeveloped northeast.

Her shack is cobbled together from bits of wood and perches on stilts over a giant puddle of fetid water below. To eke out a living for herself and her 2-year-old daughter, Lourenco ventures into a nearby swamp to hunt for crustaceans she hawks for $2.50 a kilogram.

"I think I got Zika or some other disease not long ago," she said. "What can we do? Just hope that it doesn't affect the baby."

Zika is spread by the Aedes aegypti mosquito, which is well-adapted to humans, thrives in people's homes and can breed in even a bottle cap's-worth of stagnant water -- not to mention the pools of rain water that lurk in just about every nook and cranny during the muggy summer rain season. While anyone can be bitten by Aedes, public health experts agree that the poor are more vulnerable because they often lack amenities that help diminish the risk, such as air conditioning and window screens.

The only precautionary measure Lourenco could possibly take, long-sleeve clothing, is unworkable in the unrelenting equatorial heat.

Like many of the estimated 400,000 women currently pregnant in Brazil, she can't afford mosquito repellent. Microcephaly fears have sparked a run on repellents, emptying out the stock in many pharmacies in hard-hit areas; where it's still available -- often fishing supply stores -- it now often costs several times the normal price.

The government has pledged to start providing repellent to low-income women and promises to deploy some 220,000 members of the Armed Forces to help eliminate Aedes' breeding places as part of President Dilma Rousseff's declared war against the insect. But the measures are too little, too late for women whose worries about microcephaly have transformed their pregnancies into a period of unending anguish.

In the Central American nation of El Salvador, where authorities have urged women to put off pregnancy for two years, Guadalupe Urquilla is struggling to take fate into her own hands.

She's traded her dresses for long pants and closed shoes, scrubs out the family's concrete water tank every three days, and writes San Salvador city officials, demanding that they fumigate the debris-strewn public housing complex where she lives with her husband and 2-year-old daughter.

Urquilla said her husband is believed to have had Zika last fall and her daughter had dengue.

"We're really scared," said Urquilla, who's in her 13th week of pregnancy. "Imagine my baby does not get Zika, but imagine how stressed out it will be when it comes out. The whole pregnancy we're stressed out about mosquitoes. ... It's a huge paranoia."

Lourenco, though, is more fatalistic.

"If you have to get sick you will get sick," she said. "It's everywhere."