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How To Determine The Date Of Conception?
Question: Is it possible to get a positive 8 days after conception according to my first ultrasound I conceived on January 25th. I was late of February 1st, so on the 2nd I took 4 test clearblue 25miu sensitivity. according to ultrasound I was 8 days pregnant the day I got 4 positive test? I could see with a blood test but with 25miu test. I think I had to have conceived closer to the 20th?
Brief Answer:
Ultrasound helps in knowing duration of pregnancy
Detailed Answer:
Hello dear,welcome to healthcare magic.I understand your concern.
In my opinion the clear blue test helps to know whether the pregnancy is there or not.
It helps in early detection of pregnancy 5 days before the expected period.
It might not be used to calculate the duration of pregnancy.
But the duration of pregnancy can be calculated from the last menstrual period and ultrasound.
Even the ultrasound might give a result which is variable by 5 days during the 1 st trimester.
The first trimester ultrasound is more reliable than 2 nd and 3rd trimester scans as they vary by 8 and 16 days respectively.
Hope this satisfies your query.
Feel free to discuss further.
Best regards...Dr.srilatha
Ultrasound helps in knowing duration of pregnancy
Detailed Answer:
Hello dear,welcome to healthcare magic.I understand your concern.
In my opinion the clear blue test helps to know whether the pregnancy is there or not.
It helps in early detection of pregnancy 5 days before the expected period.
It might not be used to calculate the duration of pregnancy.
But the duration of pregnancy can be calculated from the last menstrual period and ultrasound.
Even the ultrasound might give a result which is variable by 5 days during the 1 st trimester.
The first trimester ultrasound is more reliable than 2 nd and 3rd trimester scans as they vary by 8 and 16 days respectively.
Hope this satisfies your query.
Feel free to discuss further.
Best regards...Dr.srilatha
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Yes. But I had missed my period when I took the test so when I got positives I went in it was to early to see anything but they said I was 2-3 weeks. And when I went back it said I was 6 weeks 4 days date of conception January 25th. I honestly think it was wrong. Its not normal to ovulate 7-8 days before your period is due. I'm almost certain I conceived closer to 20th which would match up perfect with the error, as I cant be mad it is impossible to tell when sperm met the egg
I actually had an ultrasound the next month after that that measured the exact same. And when I said something they took me to 3D ultrasound and I measured closer to 14 weeks when I was supposed to be 12 weeks 4 days. So my doctor gave me a second due date of October 8 instead of 18th. Where does that put conception date? Maybe they thought I had a 28 day cycle that's why it was messed up. Even then it wasn't messed up by only a few days
Especially when they said I was 2-3 weeks I thought they were spot on. But the 25th would have made me one week and a day. And you don't implant until about 6 days?
I actually had an ultrasound the next month after that that measured the exact same. And when I said something they took me to 3D ultrasound and I measured closer to 14 weeks when I was supposed to be 12 weeks 4 days. So my doctor gave me a second due date of October 8 instead of 18th. Where does that put conception date? Maybe they thought I had a 28 day cycle that's why it was messed up. Even then it wasn't messed up by only a few days
Especially when they said I was 2-3 weeks I thought they were spot on. But the 25th would have made me one week and a day. And you don't implant until about 6 days?
Brief Answer:
Ovulation cant be predicted in cycles other than 28 days
Detailed Answer:
Hi there,goodday.After analysing your data I would like to give my opinion.
Let me tell you one important thing.Most of the calculations and estimation in determining the conceptual date depends upon two factors like:-
1)Regularity of the cycle.
2)Rate of growth of fetus.
In a regular cycle of 28 days ovum is released on 14th day.It will wait upto 12-24 hours to receive sperm.If fertilization doesn't occur it will desentegrate.
This statement holds good for only regular 28 days cycle.
In case of people with variable cycle duration prediction of ovum release is extremely difficult and can be only done by serial ultrasound follicular studies.And also after fertilisation implantation might happen between 3-5 days.
This is also variable in different women.
So as you have taken the test after missing the period the implantation might have occurred any day in the 2 nd half of your cycle.
As I explained earlier the rate of growth of fetus also varies with maternal nutrition ,genetical and other factors.
So the rate of growth is very much variable in the initial weeks in different people.But the first trimester scan within 12 weeks is more reliable.
Hope this satisfies your query.
Feel free to discuss further.
Best regards...Dr.srilatha
Ovulation cant be predicted in cycles other than 28 days
Detailed Answer:
Hi there,goodday.After analysing your data I would like to give my opinion.
Let me tell you one important thing.Most of the calculations and estimation in determining the conceptual date depends upon two factors like:-
1)Regularity of the cycle.
2)Rate of growth of fetus.
In a regular cycle of 28 days ovum is released on 14th day.It will wait upto 12-24 hours to receive sperm.If fertilization doesn't occur it will desentegrate.
This statement holds good for only regular 28 days cycle.
In case of people with variable cycle duration prediction of ovum release is extremely difficult and can be only done by serial ultrasound follicular studies.And also after fertilisation implantation might happen between 3-5 days.
This is also variable in different women.
So as you have taken the test after missing the period the implantation might have occurred any day in the 2 nd half of your cycle.
As I explained earlier the rate of growth of fetus also varies with maternal nutrition ,genetical and other factors.
So the rate of growth is very much variable in the initial weeks in different people.But the first trimester scan within 12 weeks is more reliable.
Hope this satisfies your query.
Feel free to discuss further.
Best regards...Dr.srilatha
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Thank you. Its just crazy to think about technically they did tell me I was a little further along than they thought. When I was supposed to be 12 4days I was 13 weeks and 6 days. Since my cycles are consistent with 22-23 days. There is no telling when I ovulated?
I guess I knew I was pregnant on the first. I was noticeable bloated its just hard to believe all that happened in 7 days. But I'm on schedule now to be due October 7th. So maybe the first ultrasound was wrong or I've been growing extremely big, but ever since my last first trimester ultrasound I've messed consistent since
I guess I knew I was pregnant on the first. I was noticeable bloated its just hard to believe all that happened in 7 days. But I'm on schedule now to be due October 7th. So maybe the first ultrasound was wrong or I've been growing extremely big, but ever since my last first trimester ultrasound I've messed consistent since
Brief Answer:
yes you are right.
Detailed Answer:
Hi there
in calculating the probable date of conception we need to consider few facts.
1.in any cycle second half is constant so in your case of 22-23 days cycle we can split it in to 8+14 days.
so in your case ovulation might have happened on 7th 8th or 9th day after your last menstrual period.
2 the viability of egg is 12-24 hrs so lets add one more day to it.
3.implantation take place after 3-5 days and hormones will start producing only after implantation.Hormones in blood will raise more quickly than urine.
but doing all the calculation,we can say that probable date of ovulation might be XXXXXXX 18.
implantation might be on 22-24 th XXXXXXX
this is only a calculation and estimation.
this might match with ultrasound with slight variability which is acceptable.
kindly have look to this piece of research.http://www.ncbi.nlm.nih.gov/pubmed/0000
feel free to discuss further.
Dr.srilatha
Gynecologist & infertility specilist
yes you are right.
Detailed Answer:
Hi there
in calculating the probable date of conception we need to consider few facts.
1.in any cycle second half is constant so in your case of 22-23 days cycle we can split it in to 8+14 days.
so in your case ovulation might have happened on 7th 8th or 9th day after your last menstrual period.
2 the viability of egg is 12-24 hrs so lets add one more day to it.
3.implantation take place after 3-5 days and hormones will start producing only after implantation.Hormones in blood will raise more quickly than urine.
but doing all the calculation,we can say that probable date of ovulation might be XXXXXXX 18.
implantation might be on 22-24 th XXXXXXX
this is only a calculation and estimation.
this might match with ultrasound with slight variability which is acceptable.
kindly have look to this piece of research.http://www.ncbi.nlm.nih.gov/pubmed/0000
feel free to discuss further.
Dr.srilatha
Gynecologist & infertility specilist
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
I think you are right that was the exact day we were trying and I thought I was ovulating
Brief Answer:
Go with your calculated date only
Detailed Answer:
hi there
in your next scan tell your radiologist or sonologist to consider this fact and check more accurately possible.
Hope I am able to answer your query.
feel free to discuss further.
I wish you happy pregnancy and also for a normal delivery.
regards
Dt srilatha
Go with your calculated date only
Detailed Answer:
hi there
in your next scan tell your radiologist or sonologist to consider this fact and check more accurately possible.
Hope I am able to answer your query.
feel free to discuss further.
I wish you happy pregnancy and also for a normal delivery.
regards
Dt srilatha
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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