What is the absolute earliest safe and healthy delivery date?

I am not totally sure, the earliest I had mine was 1 week before due date (My eldest was due on Oct. 22, but came on the 16th, and my second was due on the 16th, but came on my birthday, the 22nd). Pretty funny huh?

But back on answering your question, I think it depends. My new grandson is going to be induced a month before due date if everything is sufficiently developed. He will stay in the hospital a week though.

I always heard that anything prior to the 7th month was really dangerous. But I think even just a few weeks premature has its risks. That's why they try to stop premature labor whenever they can.

according to widipedia (http://en.wikipedia.org/wiki/Limit_of_viability):

The limit of viability is the gestational age at which a fetus/infant has a good chance of surviving outside its mother's womb without major impairment. With the support of neonatal intensive care units, the limit of viability in the developed world has steadily declined over the last 50 years. Currently the limit of viability is considered to be around 23 weeks by most neonatologists.