(CNN) -- Dan and Susan Hartmann are HIV discordant. He has HIV; she does not. They always have protected sex, which was never an issue, until they wanted to start a family. The Centers for Disease Control and Prevention recommends that people like Susan, who are in a discordant relationship, take pre-exposure prophylaxis, or PrEP, to protect against personal HIV exposure. But there is little research on how the medications affect a fetus. Meanwhile, adoption can be complicated when one parent is HIV positive. Assisted reproduction using IVF and techniques such as sperm washing (ridding the sperm of the virus before creating an embryo with an egg), are costly and illegal in some states, like California in 2007, when the Hartmanns were living there.
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Dan and Susan Hartmann wanted to start a family, but Dan is HIV-positive
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They sought out technology and medical guidance about what to do
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The answer surprised them: Try having unprotected sex
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The Hartmanns now have a healthy daughter, and Susan does not have HIV
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Hartmanns
Over dinner one night, one such expert made a suggestion the @placeholder describe as shocking: having unprotected sex.
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Dan
Dan
Because @placeholder had an undetectable viral load and they were in a monogamous relationship, the physician explained, the risk of Susan becoming infected with HIV from unprotected sex with her husband was low.
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Susan
Susan Hartmann
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Some days, he woke up reminding himself that @placeholder was more likely to get struck by lightning than to become infected this way.
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Susan
Susan Hartmann
Susan
At three months, @placeholder's test results came back negative, which tempered concerns as they shared the news of Susan's pregnancy with family and friends.
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Susan
Susan Hartmann
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At three months, Susan's test results came back negative, which tempered concerns as they shared the news of @placeholder's pregnancy with family and friends.
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It would have been more shocking for Susan to have gotten @placeholder than to have not," he says.
Dan
Dan
Dan
For now, @placeholder is living the life he once thought he'd never live to see.
Susan Hartmann
Susan
Susan Hartmann
Susan
He'll get to die of a heart attack in his 70s, @placeholder jokes, just like everyone else.