is counting my Weeks by my last period better then going by a sonogram. Which way is better?

Answer 1

Dating from your LMP is most accurate, unless the sonogram shows you are way off. My doctor never changed my due date even though my sonograms were always showing a due date that was different by a week.

Answer 2

Counting weeks by first day of last period can be fairly accurate but depends on several factors not least the length of time between periods. Sonograms are very accurate at dating pregnancies and is done around 12 weeks. This should give you a definite number of weeks and days from which to work from. Most Doctors will not change your date if the scan date falls within a week that your period suggests. A term pregnancy falls within the region of 37-42 weeks with the average first pregnancy being 41 weeks and one day and second and subsequent being 40 weeks and 6 days. This suggests that maybe we should consider a pregnancy to be 41 weeks instead of 40 and in fact in some countries follow this rule.

Answer 3

NO... go by your sonogram. It should be on target with the development of your baby more so than your period. Some people ovulate later than the normal 14 days so this could through your dates off. Not every one has a perfect 28 day cycle.. and that's what your due date from your LMC is calculated by!

Congrats and best of luck!

Answer 4

Your doctor will go by the sonogram, I know cause thats what they do with my pregnancy. There is no "best" way. Babies on average, need 40 weeks to cook. But any time between 36 and 42 is considered normal, its really up to the baby.

Answer 5

a sonogram is most accurate but only in the first 12 weeks of pregnancy

Answer 6

Go by the sonogram because the take measurements and can pin point the baby's age that way.

Don't focus on any date to much though, babies are notorious for doing what they want and that might include coming late or early!

Answer 7

The sonogram is most accurate because not all women ovulate at the same time in their cycle.

Answer 8

Early in this pregnancy my doc moved my due date up one week based on my u/s. I know beyond doubt that my dates were correct (b/f and I were going through a dry spell so I know exactly which day I conceived). But the earlier they do your ultrasound the better they are able to tell...certain things happen in certain weeks earlier on...it's harder to tell later on, since all vitals are already developed and the baby just needs to grow bigger. Only thing I wonder is since mine and doc's dates are a week off, will this affect decision of when to induce me if the need arises...

Answer 9

A sonogram, but it also depends on if you have a history of irregular periods

Answer 10

You know what its hard. I under went invetro which speed-ed up my process by three weeks and they never got things right. Just keep all your appointments and do the right thing. If you feel there is any issues don't let them tell you its normal.

You can go back and review my issues I posted last year about my pregnancy. I ended having diabetic, placenta previa and major weight gain. Stay on top of things and this forum really helped me.