My husband and I did the math and we figured that I was 3 weeks pregnant. I talked to my doctor and she said that I am 5 weeks pregnant. I told her the same date that my husbnad and I calculated from so why is it different?
2006-10-18 09:43:47 · 14 answers · asked by Justme 2 in Pregnancy & Parenting ➔ Pregnancy
You may be calculating from the conception date.
The doctors calculate it from the first day of your last period. That would throw it 2 weeks off.
Take the first date of your last period and count 40 weeks. That should be your due date.
2006-10-18 09:45:56 · answer #1 · answered by Keith Perry 6 · 2⤊ 0⤋
You probably figured you were three weeks from conception but doctors us the first day of your last menstrual cycle to determine how far along you are. Most women ovulate 14 days after their first day of their period.. (which is why everyone is saying tack on two weeks) You may get a better idea exactly how far along you are when you get your 1st ultrasound but studies have shown that is almost just as good as the formula below.
Here is the formula most docs use to determine due date and how far along you are. There are many other formulas but this is the one most commonly used.
(1st day of last period + 7 days) - 3 months) = Due Date
Most women dont keep track of the exact date of the 1st day of their last period that is why most docs will have a 2 week window around the calculated due date. If you go into labor 2 weeks before your due they wont try to stop labor and they will let you go a week "over" 2 weeks max. I always thought my daughter was born 1 week after her due date but a month after she was born I found a calendar that I had circled the 1st day of last period and it was different than the date I gave the doc so she was actually born right on time.
Good Luck and enjoy your pregnancy and the little one!!!!
2006-10-18 16:52:23 · answer #2 · answered by Kristin Pregnant with #4 6 · 0⤊ 0⤋
Someone must be calculating this wrong! If the baby is born two weeks early you will be right-if the baby comes close to the date it is due then the doctor is right. I am not sure how they figure it but most of the time the doctors figure it about right within a few days! If the doctor is right then that will be two weeks less of waiting. Hope you have a nice healthy child!
2006-10-18 17:02:37 · answer #3 · answered by Anonymous · 0⤊ 1⤋
Your period is calculated from the first day of your LMP. The first 2 weeks you are not actually pregnant. You are probably calculating from your ovulation/conception date. If you are 5 weeks pregnant, the baby has actually only been in you for 3 weeks.
2006-10-18 16:46:18 · answer #4 · answered by Melissa 7 · 0⤊ 0⤋
Go back 3 months from the start of your last period and add 7 days.
So if your last period was Sept.13th your due date is June 20th.
It's kinda confusing but it really does work out that way.
It's not unusual for the first born to be 2 weeks early or 2 weeks late. My first was due Christmas day and was born Dec. 12th
Congrats and may God be with you and your family
2006-10-18 17:03:50 · answer #5 · answered by KieKie 5 · 0⤊ 0⤋
How did you calculate it? Doctors sometimes vary the way it's added up because it's not really an exact science yet. Only the ultrasound will really tell for sure.
Normally, you take the first day of your last period. Then add 40 weeks.
2006-10-18 16:46:58 · answer #6 · answered by Heck if I know! 4 · 0⤊ 0⤋
For whatever reason, they calculate the begining of life of a baby from the creation of the egg--not fertilization.
Unless people are talking about how birth control doesn't cause early abortions--suddenly the life of the baby doesn't even begin at fertilization, but at implantation. Go figure.
2006-10-18 16:56:31 · answer #7 · answered by Mary's Daughter 4 · 0⤊ 0⤋
You have to start adding the 40 weeks from the first day of your last period... not the day you had sex and actually conceived. Therefore, 38 weeks from the time you conceived (babys only stay inside of you for 38 weeks)... its just counted from your last period because of the fact that you really could have ovulated any time after your period.
2006-10-18 16:45:40 · answer #8 · answered by Ashley P 6 · 2⤊ 0⤋
doctors calculate from your last period. The first day of your last period, which is always about 2 weeks before you concieved, thats why hers is 5 and yours is 3.
Follow hers, not yours.
2006-10-18 16:45:48 · answer #9 · answered by amosunknown 7 · 3⤊ 1⤋
They tack on 2 weeks for some reason.
2006-10-18 16:49:53 · answer #10 · answered by Emily O 3 · 0⤊ 1⤋