Pregancy due date?

Question

I dun quite understand how's the calculation done.

Doctors calculate from the 1st day of the last period & so on. But my 1st day of my last period is on 01/5. Then the app counted my conception date to b on 15/5 (with the Tww) and with that, due date is 05/2/16.. but i only had sex on 23/5 during my ovulation period. How is that possible?

The app counted that i'm 5-6weeks pregnant on the go now. How accurate is that?

When does conception actually takes place? Some say on the 3rd day after u had sex for successful concieved cases.

I feel so puzzled. Need some enlightenment pls...

Answer

It's all just estimation. Drs base it off your lmp, and estimate that conception takes place about 2 weeks later, but that is based on a perfect 28 day cycle.

Answer

I worked mine out based on 1st day of lmp, and went for my first u/s at 7wks4days based on that calculation. 
​When they did the u/s they said I was only 6wks2days. This would be because I ovulated later than I thought/because I have longer cycles. 
​Confused the heck out of me and I didn't know which date to use. 
​I'm going by the u/s date because even if they move it later on, at least I've done the 'going backwards' bit... Which really, really sucked!! I felt like I was stuck at 8 weeks for a lifetime! 
​I'm now 10wks2days, and will be going for my next u/s in about another week, so I'll see what they say then!

Answer

It's all different depending who you talk to but as far as the due date medical professionals will use, that is the one calculated from the first day of your last menustral period.

Pregancy due date?

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