(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
It would have been more shocking for Susan to have gotten @placeholder than to have not," he says.