Sorry, LMP means last menstrual period.

A due date of 23rd May is not consistent with a scan that showed 5w4d on Saturday. I'm presuming you meant you had the scan on Sat 11th October (you typed 13th and that's today's date. If Sat 11th Oct is correct and you were 5w4d on that day then the due date based on a 28 day cycle (most GPs & OB's will calculate it that way regardless of the length of your cycle) is 9th June 2009.

You don't count the 5w4d from conception, it's from the LMP which in your case would be estimated to be around 2 weeks before ovulation date. So bubs is actually around 3w4 days in reality but would be referred to as 5w4d. So when you reach 40 weeks bubs is really only 38 weeks (when you take off two weeks that it takes on average to release an egg after your period arrives).

I hope that hasn't confused you, but I probably have.

Anyway based on the scan I still say you would be due 9th June. Not that it matters, bubs usually don't arrive on their EDD anyway as of course it's only an estimate. With different doctors opinions and scans I was due somewhere between 28th June to 3rd July but bubs arrived 23rd June.