I don't think you need to worry at all. You seem to be an old member of CiteHR, and I am sure you would have seen many postings/threads from Lady HR professionals who took breaks of years (for kids' sake) and still managed to rejoin jobs. The only difference between you and them is the reason for the gap. As long as you are able to authenticate the gap (through medical certificates), it shouldn't be a problem. The only aspect could be this: it could take a bit more time for you to get a job than it would for others who are currently working.
Please ensure you mention 'Medical Reasons' for the gap in your resume—please don't leave this gap unsaid or unexplained—the recruiter will then make his/her own assumptions, which may not be to your advantage. You can explain the complete reasons during the interviews. Hope you get the point.
All the Best,
Regards, TS