Well, anything is possible. Since there is no training cross-over, you'd be doing 7 years of residency and there's no guarantee of getting a second match (after you finished the first residency) since that would not likely get medicare funding. However, who knows? Someone might take you.
Then, once trained, you'd have to deal with an unusual job split. A half-time OB is likely paying full-time malpractice, etc. There are other obvious logistic issues with such a career and setting up such a single office.
So, go for it if that's your dream! But, I'd recommend choosing one of the two.