Can't remember with my first one (nearly 24 years ago), probably a few weeks/a month.
With my daughter though I could have had sex a couple of hours after later as when I left the hospital and walked from the car to my house I felt as right as rain and like I'd bought my daughter from a shop rather than having just given birth a few hours earlier that morning.
Both labour's were fairly short, easy, no pain relief and no tears/stitches.
I remember feeling a bit tired after my son was born but with my daughter I think there was a feeling of euphoria, but tempered with giving birth so that I just felt completely normal.
Its possible that the woman in question was feeling euphoric?