Bringing "girlfriend" to US so as to be surrogate for IVF

[npe1jar]

I know this post will be viewed with skepticism, but I'm somewhat desperate. The situation is as follows:
1. My GF and I are looking to have kids but need to use IVF and need someone to carry the baby
2. We have a friend in Jamaica (JB) who is willing to do this for us
3. We are looking for the best way JB to come to the US legally and have considered the visitor visa
4. Once she came with visitor visa, we would do the IVF procedure and she would be pregnant
5. Then it seems we would need to apply for an extension

Does anyone know the best way to handle this extension application?
Would the fact that she would be pregnant make it more or less likely that the extension be approved?
If she was denied, would she be able to go back to Jamaica for a month or so and then come back to the US? (note that zika concerns make this an unwanted option)

Side questions (here's where it gets sketchy)
6. If we were to have me marry JB would that make it more likely that she be able to stay legally for the birth?

Thanks to you all who contribute.

[inadmissible]

Indeed, medical tourism (including for birth) is an appropriate use of the visitors visa. Visitors with deep pockets do it all the time. The twist here is that you will have to prove your ability to support her, rather than her providing her own proof of financial resources and medical insurance. Charities with deep pockets often sponsor the visas of children receiving their funding for medical care in the United States

That said, be prepared to deal with the fact that consulate officers in Jamaica tend to presume that tourist visa applicants have immigrant intent. That is, they have such weak ties to their home that they may take the opportunity of a temporary trip to the United States as an opportunity to live there permanently by overstaying their visa. In addition, surrogacy is regarded as an inherently commercial arrangement. As such, the US consulate will be highly skeptical of the claim that she is carrying your baby gratuitously. A commercial arrangement requires a work visa, which is difficult to obtain

You should certainly not marry her and let her apply for immigration benefits on that basis, because what is described is not a bona fide marriage. Even if she were to be the mother of your child, if the two of you do not intend to make a life together, then that would be immigration fraud which will render her permanently inadmissible from the United States