(CNN) Ana Cássia has always wanted to be a mother. She and her childhood sweetheart, Alberto, knew from the get-go that they wanted a big family.
They dated for 10 years before getting married in 2006, and when they went looking for an apartment, their plans to grow their family were a big factor in their search. The Salvador apartment they settled on has both an extra room and a playground below -- a perfect family home -- and last year, they decided it was finally time to begin realizing their dream of having children.
They faced some obstacles, though. It turned out that Cássia had endometriosis, so they sought the help of Dr. Genevieve Coelho, the director of IVI Salvador, the largest fertility center in Salvador, Brazil's third largest city.
But then came another hurdle.
Late last year, on the heels of an advisory from the World Health Organization, the Brazilian government took the unusual step of advising women to delay pregnancy because of concerns about Zika-associated microcephaly.
"We were planning to get pregnant this year. But because of Zika, we've decided to wait more. There isn't much that we can do about it, and it worries us," Cássia told CNN's Dr. Sanjay Gupta through an interpreter.
After the WHO advisory linking Zika to microcephaly -- a rare birth defect that results in an underdeveloped brain -- there was a sharp drop in patient requests for fertility help at Coelho's clinic. "We had a drastic reduction, nearly 70%," Coelho said. And that concerned her. "If someone comes to you at 38 years old and then she's delaying for one year or two, she'll be 40. That has a drastic effect on the ovarian reserve."
Coelho said that for patients like Cássia, who are already having difficulty getting pregnant, ZIka is an added stressor. "(Cássia) was very, very depressed. I suggested, 'We can freeze your embryos, and then later, when there is a solution or a light at the end of the tunnel with the Zika virus, you can decide to transfer the embryo to your uterus.' "
It wasn't what Cássia initially envisioned, but she and Alberto decided to opt for freezing their embryos "once all the Zika and microcephaly issues came up," she said.
Coelho said the success rates of pregnancies using IVF techniques are quite high. Other experts note that sperm frozen up to 12 years has resulted in successful pregnancies and that embryos can be kept 10 to 15 years.
The options may have preserved Cássia's dream. She told Gupta that she and her husband have been following the latest news about Zika.
"We've been researching and reading a lot about Zika's relationship with microcephaly, and due to new research and results, like the Zika blood tests that can tell you if you had Zika in about five days, we are thinking of going to the fertility clinic and trying to get pregnant again soon."
Coelho said she has patients who are moving abroad during their pregnancies to stay safe. But she points out that moving, or fertility treatments, aren't feasible for most Brazilians. "Those who can afford it, they come here; they freeze their eggs; they freeze their embryo. They have an option. They have an option, but most of the Brazilian population, I would say 80%, doesn't have the choice more because of the financial expense of the treatment."
Freezing eggs can cost about $3,000 U.S., and freezing embryos can cost at least twice as much. But the average monthly income in Brazil is just a few hundred dollars a month.
Like Cássia, 23 year-old Vanessa Neves and her husband, Bruno Nascimento, have chosen to delay starting a family. They have been married for five years, and like Cássia, they chose their apartment with a baby in mind. But unlike Cássia, they aren't using fertility treatments. They have decided to postpone having a child for another two or three years. Neves may have the benefit of age when it comes to her fertility, but she says two or three years is still a long time to wait.
"It's hard. ... The child isn't even born yet, but if it's a girl, we will name her Valentina. But we're worried. It's sad, because there's no way to know. We will wait until the situation improves and is safer," she told Gupta.
What worries Neves and Nascimento is not simply the possibility of having a child with microcephaly but the prospect of caring for one. What would they need? Would they be able to provide the child with all the resources he or she requires?
As much as the government has emphasized delaying pregnancy, Coelho says it hasn't fully thought out how to implement such a directive. "They are not making the proper measures to delay pregnancy, like distribute condoms or contraceptives. In essence, Zika has become a proxy for the haves and have-nots, and much of the burden of the disease is being carried by women."
"If you go in the poor areas, you don't have proper contraceptive methods. The children here, the women here, at 15, 16, 17, they get pregnant. If adult women control pregnancy, you don't have proper methods," said Coelho. She described it as a social disease, noting that the highest incidences of microcephaly were occurring in the poorer parts of the country. "Even the product you use to avoid the mosquito bites, it's not distributed free. It's quite expensive for the average salaried Brazilian."
Tarah Demant, senior director of the Identity and Discrimination Unit at Amnesty International, told Time, "They don't have access to information, they don't have access to contraception, and they don't have access to the option to terminate a pregnancy."
Abortion in Brazil is legal only in incidences of rape or if the mother's life is at stake.
But a recent study from the New England Journal of Medicine found that requests for abortions through the group Women on Web, a nonprofit that provides online access to the abortion drugs mifepristone and misoprostol, jumped 108% in Brazil between January 2010 and March 2016.
"It isn't enough for health officials just to warn women about the risks associated with Zika," said study author Dr. Catherine Aiken, a lecturer in the department of obstetrics and gynecology at the University of Cambridge. "They must also make efforts to ensure that women are offered safe, legal and accessible reproductive services."
For those women lucky enough to afford a choice, like Cássia, it's a choice that comes with a price: postponing their dreams of becoming a mother.
Cássia shows Gupta the spare room that she intends to turn into a nursery, excitedly pointing out that she wants to put the crib under the window so the baby can look outside and have fresh air. Cássia says she also has many ideas about how to decorate the room.
"The only thing we're missing now is materializing this dream and making this project come true."