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Is this always true?

"Using an ultrasound to look at your baby, your doctor will be able to tell you how many weeks pregnant you are. If you subtract two weeks from this number and count backwards with a calendar, you can determine your approximate ovulation date"

Answer Question

Asked by Anonymous at 4:34 PM on Apr. 28, 2009 in Pregnancy

Answers (5)
  • I would assume that it is correct. That's the way they figure out your due date. They just count the opposite way.

    Answer by LilyandEmmasMom at 4:39 PM on Apr. 28, 2009

  • I don't agree with that and it confuses me. U/S go by the average size of an embryo, so if it says you are 7 weeks, pregnant: you are 7 week pregnant. Subtracting 2 weeks would make you 5 weeks pregnant... . It takes 10-14 days once an egg has been fertilized for it to even implant. You wont produce HCG until the egg has implanted. I don't understand this *quote* though., If anything you'd have to add 2 weeks. If you subtracted you'd just make yourself less pregnant then you really are?!

    Answer by celticreverie at 4:40 PM on Apr. 28, 2009

  • never mind. subtract two weeks, then count back. God. It would make sense then. ignore me lol. preggo brain misread.

    Answer by celticreverie at 4:41 PM on Apr. 28, 2009

  • Your due date is an estimate and not an exact date. They can not say you ovulated on this day as its a matter of when the sperm and egg meet and fertilize. It could be early or late. WHy is it so important anyways? Its not the same every month because if that was the case it would be really easy for us all to only have sex one day a month. WOrry about having a healthy baby and not what day you may have ovulated as its impossible to tell unless you have a camera watching your ovaries daily.

    Answer by Anonymous at 4:41 PM on Apr. 28, 2009

  • It depends on how far along you are when you get the ultrasound. Babies grow at the same rate during the first trimester so the date would be pretty accurate give or take no more/no less than 4 days. If you're in your 2nd trimester it's harder to tell due to all babies growing at different rates (but there is a default measurement) I got my 1st ultrasound at 10weeks 6 days and it matched EXACTLY with my conception date. I got my 2nd ultrasound at 22 weeks and his length and weight were exactly where they were supposed to be. I would say if you don't know your LMP and you get an ultrasound when you find out your preggo the date should be accurate. You can also keep tabs on when you feel the baby move and changes in your body, that also helped me.

    Answer by Niecey35717 at 5:12 PM on Apr. 28, 2009

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