I don't know why I feel compelled to answer this, but I do.
For me, the answer to this question is a no-brainer. I would sooner choose adoption than IVF or surrogacy, no question. It's not that I'm morally opposed to either of those, but I would not be willing to take the risks inherent in those options. IVF and surrogacy are very expensive and there is no guarantee that the implanted embryos will 'take'. There is also no one I am close enough or trust enough to be a surrogate. I guess I'm close enough to my sisters, but I would never ask them because it would be too weird. I would feel like I was stealing the kid when it was born. I would also be concerned about the surrogate having a difficult time giving up the child after carrying it for 9 months.
Adoption is a long process and also expensive, but in the end, you're guaranteed a kid. Plus, those kids need good parents and I'd rather give someone who already exists a better chance in life than attempting to bring another into the world.
And on a superficial note, with adoption, no weight gain and stretch marks. ;-)