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How To Determine Date Of Conception?
Question: Would it be possible to get pregnant on the 24th of January and get 4 positive pregnancy test on the 2nd of February with 25miu sensitivity. I am under the assumption that it is to early?
Brief Answer:
conception date
Detailed Answer:
Hello,
Thanks for the query to hcm,
If she has conceived by XXXXXXX 24th then likely that her LMP should be around 8-10 XXXXXXX And usually urine pregnancy tests are unable to detect pregnancy until 7 days post missed period and usually have a high false positive rates. So the best test after a week post intercourse is the serum beta hcg test which is sensitive to even 1 ng/dl of hcg in the blood and hence highly sensitive and specific for pregnancy.
If her LMP was 10th XXXXXXX then her fertile period would have started from 20jan and lasted till 4 feb, ovulation would have occured
by 22-24 XXXXXXX and if you have had sex in that period she could have got pregnant then. As her next menses were due only by 10th feb, the symptoms of pregnancy like bloating, nausea, headache, all due to increasing hcg would have manifested and if you used pregnancy test kits with 25miu sensitivity then they should have showed correct results of positive pregnancy as hcg concentration doubles every second day , so it would be definitely more than 25miu when she measured on 2 feb.
I hope i have answered in detail here.
Regards
conception date
Detailed Answer:
Hello,
Thanks for the query to hcm,
If she has conceived by XXXXXXX 24th then likely that her LMP should be around 8-10 XXXXXXX And usually urine pregnancy tests are unable to detect pregnancy until 7 days post missed period and usually have a high false positive rates. So the best test after a week post intercourse is the serum beta hcg test which is sensitive to even 1 ng/dl of hcg in the blood and hence highly sensitive and specific for pregnancy.
If her LMP was 10th XXXXXXX then her fertile period would have started from 20jan and lasted till 4 feb, ovulation would have occured
by 22-24 XXXXXXX and if you have had sex in that period she could have got pregnant then. As her next menses were due only by 10th feb, the symptoms of pregnancy like bloating, nausea, headache, all due to increasing hcg would have manifested and if you used pregnancy test kits with 25miu sensitivity then they should have showed correct results of positive pregnancy as hcg concentration doubles every second day , so it would be definitely more than 25miu when she measured on 2 feb.
I hope i have answered in detail here.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
My doctor told me 8 days was way to early to get a positive even with some of the most sensitive test her cycle is not regular and she is 25 weeks and and few days pregnant which puts conception date around 14-20th does that sound right. My doctor said that lines up perfect for positive pregnacy test 2 weeks later as she took those test 6 days before her period was due. I'm thinking she has to have a 20 day cylce to have gotten pregnant basically right after her period
The way it was explained to me it takes 6 days for implantation. And only after then do you start producing hcg, and by 8 days he said she would be lucky if her levels were 15. Is this right?
The way it was explained to me it takes 6 days for implantation. And only after then do you start producing hcg, and by 8 days he said she would be lucky if her levels were 15. Is this right?
Brief Answer:
answered
Detailed Answer:
If her gestational age is 25 weeks from LMP then it should be 10th XXXXXXX around. And i agree that urine pregnancy tests are not sensitive until 8 days post missed periods.
But they may always give a false positive result if done prior to missed periods depending on the brands available.
So, the pregnancy is always reconfirmed at that stage with serum beta hcg and thereafter by USG.
iF FOR DEFINITE HER LMP was 10th XXXXXXX then she should be getting pregnant only after XXXXXXX 20th as before that ovulation doesn't take lace and hence conception cannot occur.
Only in rare possibilities where an ovum from previous cycle remained intact and ruptured during the next cycle which got fertilised then, may exists but its rare. The USG age of gestation doesn't conform to this theory in your wife's case here so she conceived only after XXXXXXX 20th.
Urine pregnancy tests kits can be deceptive and should never be used as bench marks before missed periods.
Regards
answered
Detailed Answer:
If her gestational age is 25 weeks from LMP then it should be 10th XXXXXXX around. And i agree that urine pregnancy tests are not sensitive until 8 days post missed periods.
But they may always give a false positive result if done prior to missed periods depending on the brands available.
So, the pregnancy is always reconfirmed at that stage with serum beta hcg and thereafter by USG.
iF FOR DEFINITE HER LMP was 10th XXXXXXX then she should be getting pregnant only after XXXXXXX 20th as before that ovulation doesn't take lace and hence conception cannot occur.
Only in rare possibilities where an ovum from previous cycle remained intact and ruptured during the next cycle which got fertilised then, may exists but its rare. The USG age of gestation doesn't conform to this theory in your wife's case here so she conceived only after XXXXXXX 20th.
Urine pregnancy tests kits can be deceptive and should never be used as bench marks before missed periods.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Doctor has conception date at January 17th though. So its not possible until 20th or afterwards? So then the 17th cant be right then?
He told me and my wife that she conceived 2-4 days after bleeding stopped. From measurements. This is why I'm so confused because other doctors say he's right and other say no.
He told me and my wife that she conceived 2-4 days after bleeding stopped. From measurements. This is why I'm so confused because other doctors say he's right and other say no.
Brief Answer:
answered
Detailed Answer:
Hello,
Ultrasonological age is the best measure for date of conception. So in her case then the only likelihood if that a previous unruptured follicle form the previous cycle ruptured just after her bleeding stopped and she got pregnant in her otherwise safe period.
Regards
answered
Detailed Answer:
Hello,
Ultrasonological age is the best measure for date of conception. So in her case then the only likelihood if that a previous unruptured follicle form the previous cycle ruptured just after her bleeding stopped and she got pregnant in her otherwise safe period.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
And if this helps doctor is not going by lmp since her lmp and measurements are more than a week apart she's 25 weeks as per ultrasound measurements. I am having trouble myself understanding how her lmp and measurements are so far off because i thought ovulation was on 14th day of cycle and its apparently not for everyone depending on your cycle? He said she has 20 day cycle or less.
Brief Answer:
Answered
Detailed Answer:
The best way to go in her case in with her ultrasonological age of gestation and the ultrasonological EDD is to be taken under consideration in her case as she has short cycles which are irregular.
As her cycles has always been 20 days then she is a candidate for early ovulation which occurs almost exactly in the mid cycle of every woman and thus it corresponds to 20th XXXXXXX ( day of conception). It all depend on her cycle dates.
Presently there is no other way but to go with the ultrasonological age of gestation.
Regards
Answered
Detailed Answer:
The best way to go in her case in with her ultrasonological age of gestation and the ultrasonological EDD is to be taken under consideration in her case as she has short cycles which are irregular.
As her cycles has always been 20 days then she is a candidate for early ovulation which occurs almost exactly in the mid cycle of every woman and thus it corresponds to 20th XXXXXXX ( day of conception). It all depend on her cycle dates.
Presently there is no other way but to go with the ultrasonological age of gestation.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Yes 18th-21st seems like when she conceived due to measurements. Just not lmp, doctor told me ultrasound dates are always better than lmp and also said its not uncommon for lmp to not match up with ultrasound.
Brief Answer:
answered
Detailed Answer:
Hello,
Yes i agree with the doctor completely and in this particular case we should be going by the ultrasonological dates only as these are the best dates in her case where irregularity and short cycles is a cause of dilemma.
Regards
answered
Detailed Answer:
Hello,
Yes i agree with the doctor completely and in this particular case we should be going by the ultrasonological dates only as these are the best dates in her case where irregularity and short cycles is a cause of dilemma.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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