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Used OPK And Had LH Surge, Ovulated. Done HCG Tests. Could Ovulation Have Occured?
Question: I used an OPK and had an LH surge on 5/1/12 so I am almost positive I ovulated within 36-48 hours, but I didn't have my first positive HPT until 5/23, my 1st hcg test on 5/29 came back 454 and then 1116 on 5/31. Is this normal? How far along am i or should I be? Could I have ovulated later?
hi XXXXXXX,
thanks for the query.
-as ovulation occurs after 36 to 48 hours of LH surge, then your ovulation might have occurred either on 2nd or on 3rd of May.
-some home pregnancy tests are less sensitive and they can't detect lower levels HCG, some may need 1week after missed period that may be reason for negative tests up to 23rd.
-if you take your ovulation date between 2rd to 3rd, then 29th will be 26th or 27th postovulatory day,
during that period normal levels of HCG are 10 to 425, your value 454 can be taken almost nearer to it because sometimes hours gap also counts.
-HCG will double in 31 to 48 hours, so your value on 31st, 1116 is normal according to this criteria.
according to all this,
you might have ovulated on 2nd or 3rd of May and today that is 8th XXXXXXX is your 37th or 38th postovulatory day.
means in case of regular periods it is around 5 weeks+ 2 to 3 days from ovulation,
7 weeks + 2 to 3 days from first menstrual day of last period.
Hope I have answered your query. I will be available to answer your follow up queries. If you are satisfied with all my answer, please rate the answer after closing the discussion.
take care.
thanks for the query.
-as ovulation occurs after 36 to 48 hours of LH surge, then your ovulation might have occurred either on 2nd or on 3rd of May.
-some home pregnancy tests are less sensitive and they can't detect lower levels HCG, some may need 1week after missed period that may be reason for negative tests up to 23rd.
-if you take your ovulation date between 2rd to 3rd, then 29th will be 26th or 27th postovulatory day,
during that period normal levels of HCG are 10 to 425, your value 454 can be taken almost nearer to it because sometimes hours gap also counts.
-HCG will double in 31 to 48 hours, so your value on 31st, 1116 is normal according to this criteria.
according to all this,
you might have ovulated on 2nd or 3rd of May and today that is 8th XXXXXXX is your 37th or 38th postovulatory day.
means in case of regular periods it is around 5 weeks+ 2 to 3 days from ovulation,
7 weeks + 2 to 3 days from first menstrual day of last period.
Hope I have answered your query. I will be available to answer your follow up queries. If you are satisfied with all my answer, please rate the answer after closing the discussion.
take care.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
I thought so too, but what if my ultrasound said I was between 5.5 to 5.75 weeks, just short of 6 weeks because I didn't see a heartbeat, just a yolk and sac (although I have to wait to get the exact results back next week). Does this mean that my baby is not growing normally or could I have ovulated a week later than what my LH surge had indicated?
hi XXXXXXX,
ultrasound will measure the gestational age from fertilization means almost from ovulation, so according to that it is nearer to your calculated gestational age above,
there can be 3 to 4 days disparity in first trimester scan wise gestational age and lmp wise gestational age,
so you don't bother about it.
in next scan you can see heart beat of your baby possibly, by transvaginal scan even by 5 weeks+ it can be seen.
Wish you Good Health, If you are satisfied with my response please rate the answer after closing the discussion.
take care.
ultrasound will measure the gestational age from fertilization means almost from ovulation, so according to that it is nearer to your calculated gestational age above,
there can be 3 to 4 days disparity in first trimester scan wise gestational age and lmp wise gestational age,
so you don't bother about it.
in next scan you can see heart beat of your baby possibly, by transvaginal scan even by 5 weeks+ it can be seen.
Wish you Good Health, If you are satisfied with my response please rate the answer after closing the discussion.
take care.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
OK, but one last question - could I have ovulated a week after i saw the LH surge on the OPK?
I apologize, I did not understand your comment "ultrasound will measure the gestational age from fertilization means almost from ovulation, so according to that it is nearer to your calculated gestational age above" - could you please elaborate on this as well?
I apologize, I did not understand your comment "ultrasound will measure the gestational age from fertilization means almost from ovulation, so according to that it is nearer to your calculated gestational age above" - could you please elaborate on this as well?
hi XXXXXXX,
what I meant to say is, normally we calculate gestational age from last menstrual period but ultrasound in early pregnancy will measure the gestational age according to the size of the gestational sac, which will form after fertilization only, which will occur after ovulation.
during measuring the gestational age in first trimester, three values of diameters of gestational sac to be taken and their average to be calculated and when that value is correlated with pre-prepared table values it will give gestational age.
this will depend on experience of performing person.
you didn't mention on which day you got ultrasound done.
transabdominal ultrasound will underestimate gestational age 1.6 to 2 days compared with transvaginal ultrasound.
and as such in first trimester ultrasound scan there could be 3 to 4 days disparity may be there, all together comes around 1 week .
finally what I want to tell is when LH surge is noted by the kit in 99% cases ovulation will occur by 36 to 48 hours. so we have to take it as standard.
when you take another scan next week mostly this disparity will resolve.
Wish you Good Health, If you are satisfied with my response please rate the answer after closing the discussion.
take care.
what I meant to say is, normally we calculate gestational age from last menstrual period but ultrasound in early pregnancy will measure the gestational age according to the size of the gestational sac, which will form after fertilization only, which will occur after ovulation.
during measuring the gestational age in first trimester, three values of diameters of gestational sac to be taken and their average to be calculated and when that value is correlated with pre-prepared table values it will give gestational age.
this will depend on experience of performing person.
you didn't mention on which day you got ultrasound done.
transabdominal ultrasound will underestimate gestational age 1.6 to 2 days compared with transvaginal ultrasound.
and as such in first trimester ultrasound scan there could be 3 to 4 days disparity may be there, all together comes around 1 week .
finally what I want to tell is when LH surge is noted by the kit in 99% cases ovulation will occur by 36 to 48 hours. so we have to take it as standard.
when you take another scan next week mostly this disparity will resolve.
Wish you Good Health, If you are satisfied with my response please rate the answer after closing the discussion.
take care.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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