Why do we calculate the length of a pregnancy from the first day of a women’s last period?
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Fun fact: I don’t know if it’s the same everywhere, but with animals you count the gestation time from the day of conception. Probably because you can exactly say when the day of conception was, whereas with humans there probably is multiple times in fertility time where people have sex.
We really don’t. It is a starting rough estimate. On your first ultrasound they measure multiple parts of the fetus and give a more accurate estimate of your term. after the second visit the current length of pregnancy and due date is basically solidified unless something changes throughout the pregnancy. currently going through this process with my wife. So far developmentally it is spot on accurate.
We really don’t. It is a starting rough estimate. On your first ultrasound they measure multiple parts of the fetus and give a more accurate estimate of your term. after the second visit the current length of pregnancy and due date is basically solidified unless something changes throughout the pregnancy. currently going through this process with my wife. So far developmentally it is spot on accurate.
Because it’s easier to track when you get pregnant. Imagine a couple having an active sexual life and guessing when you got fecundated, it’s easier and lots of woman do track their periods so thats why.
It’s easier because in 12 days occurs ovulation.
The imagined first day too. I remember they calculated the length and conception date with my first and I got pregnant apparently when me and my partner were in seperate countries. And no, there is no doubt it’s his child.
There’s some talk of “we don’t know when a woman ovulated” but we do know that for most women who track their periods, their ovulations, and/or are trying to conceive.
Like, my wife knows the exact day she ovulated for the kid we had. But they still go off the last period, and doctors still assume cycles are 28 days or say “it varies” even when you know how long your cycle is.
The imagined first day too. I remember they calculated the length and conception date with my first and I got pregnant apparently when me and my partner were in seperate countries. And no, there is no doubt it’s his child.
I’m not a doctor, but I am pregnant! My due date was based on the first day of my last period until my first ultrasound.
This is because it’s difficult to know exactly when you ovulate & conception occurs. I tracked my ovulation so we actually did know, but then you also have to consider the implantation process.
The embryo does not begin dividing cells and growing until it is implanted in the uterus. After that, a pregnancy test will show up positive.
Using your last period won’t always be the most accurate, but it is the easiest to track! Plus, due dates can always be changed after a dating scan if need be.
The imagined first day too. I remember they calculated the length and conception date with my first and I got pregnant apparently when me and my partner were in seperate countries. And no, there is no doubt it’s his child.
I’m not a doctor, but I am pregnant! My due date was based on the first day of my last period until my first ultrasound.
This is because it’s difficult to know exactly when you ovulate & conception occurs. I tracked my ovulation so we actually did know, but then you also have to consider the implantation process.
The embryo does not begin dividing cells and growing until it is implanted in the uterus. After that, a pregnancy test will show up positive.
Using your last period won’t always be the most accurate, but it is the easiest to track! Plus, due dates can always be changed after a dating scan if need be.
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