My daughter was born naturally at 37+5 by scan dates/37+2 by my dates. But I always sort of knew I would be early - probably around 38 weeks. My gut sort of just told me. Actually, the day my daughter was born was supposed to have been my last day of work before maternity leave and then about a month before I panicked because I wasn't sure I'd make it that long, so I changed it to be a week earlier (thankfully, means I did manage about 4 days off before she arrived!). But I really had absolutely no signs that anything would have happened when it did. No cramping, no mucus plug or show until I was in labour, not even a single BH.