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What Does This Ultrasound Report During Pregnancy Indicate?
Question: Hi Doctor, please find attached my first dating scan when I was 5 weeks 7 days by last period (20/08/2016). I have those concerns that wish you could provide me some clarification. (1). I notice my Gestational Sac was measured smaller in days (5 weeks 3 days) comparing with the fetal pole measured (5 weeks 5 days). I read on the internet that if the Sac is too small or if it does not develop fast enough, it can cause a miscarriage. Should I worry my situation that the dating measure from the Sac is slower than the dating measure from the fetal pole? (2). Should I worry that I cannot see a heart beat at this stage? Although I have no bleeding or cramp showing a sign of miscarriage but I heard there is one type called missed miscarriage where there is no symptoms experience by the woman but only an ultrasound found no heart beat later on confirmed a miscarriage. I'm really worry for my fellow up ultrasound in a week time I cannot see a heart beat again. Is this common? Thank you doctor.
Brief Answer:
it is normal...
Detailed Answer:
Hello,
Thanks for the query to HCM,
I understand your concern here completely but at 6 weeks gestation at your last scan, the foetal pole was just about being seen so with 3mm size corresponded to 5 weeks + 3 days. You need to understand that the gestational age conforming with regards to gestational sac is not taken into account for calibration of gestational age usually unless the foetal pole is not seen. Moreover, in absence of a foetal pole, if there is any irregularity in the sac wall, then a diagnosis of anembryonic gestation or chemical pregnancy is made.
Nextly , a missed abortion is said if the heart beat has once arrived and then due to some reasons have stopped. Ideally the heart beat of the foetus appears by 7-9 weeks of gestation calculated from LMP. So as foetal pole has arrived, it is likely that at your next ultrasound in a week when you would be 8 weeks + 1 days ( from lamp), YOU SHOULD SEE A FOETAL HEART RATE.
There is no apparent need to be unnecessarily worried at present as there has been no bleeding per vaginum, indicating that pregnancy is intact and growing. Though there are ways to find out foetal viability through beta hcg levels which are known to increase by 65% in next 48 hrs, if so, then foetus is considered to be adequately growing.
You should wait for your next scan with a clear mind.
To add, an ultrasonological estimation always have a 10 % discrepancy attributed to observer's bias, so please relax and enjoy your pregnancy.
Regards
it is normal...
Detailed Answer:
Hello,
Thanks for the query to HCM,
I understand your concern here completely but at 6 weeks gestation at your last scan, the foetal pole was just about being seen so with 3mm size corresponded to 5 weeks + 3 days. You need to understand that the gestational age conforming with regards to gestational sac is not taken into account for calibration of gestational age usually unless the foetal pole is not seen. Moreover, in absence of a foetal pole, if there is any irregularity in the sac wall, then a diagnosis of anembryonic gestation or chemical pregnancy is made.
Nextly , a missed abortion is said if the heart beat has once arrived and then due to some reasons have stopped. Ideally the heart beat of the foetus appears by 7-9 weeks of gestation calculated from LMP. So as foetal pole has arrived, it is likely that at your next ultrasound in a week when you would be 8 weeks + 1 days ( from lamp), YOU SHOULD SEE A FOETAL HEART RATE.
There is no apparent need to be unnecessarily worried at present as there has been no bleeding per vaginum, indicating that pregnancy is intact and growing. Though there are ways to find out foetal viability through beta hcg levels which are known to increase by 65% in next 48 hrs, if so, then foetus is considered to be adequately growing.
You should wait for your next scan with a clear mind.
To add, an ultrasonological estimation always have a 10 % discrepancy attributed to observer's bias, so please relax and enjoy your pregnancy.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Thank you doctor. Can i understand what you said as since i already see the fetal pole (I assume this is a good sign?) , it is very likely i can see a heart beat at my follow up scan? Thank you!
Brief Answer:
answered
Detailed Answer:
Yes it is good sign to see a foetal pole and there is all likelihood that foetal heart rate can be seen during your next scan.
answered
Detailed Answer:
Yes it is good sign to see a foetal pole and there is all likelihood that foetal heart rate can be seen during your next scan.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Thank you doctor. It has relieved some of my worries. I have another stupid question. I aread that the gestational sac should size at least 5mm larger than the CRL. Given my Sac was measured at 0.94cm at early stage, which is slightly larger than 5mm of the fetal pole CRL measured at 3mm. Is this consider normal? Should i expect the size if the sac growing faster in the coming weeks? I'm so worry that the fetal pole has growing faster than the sac and eventually reach the point that stopped growing. I read that sac size less than 5mm larger than CRL will almost all lead to a fail pregnancy. Thank you.
Brief Answer:
answered
Detailed Answer:
Mean Sac Diameter measurement is used to determine gestational age before a Crown Rump length can be clearly measured.The average sac diameter is determined by measuring the length,width and height then dividing by 3 .Once a fetal Pole can be visualised the CRL measurement is the most accurate method for dating the pregnancy.
According to books:-
Small sac size = MSD - CRL < 5mm
(15/16 patients with MSD less than 5 mm greater than CRL subsequently aborted*)
*Bromley B. Radiology 1991;178:375
If the sac size is less than 5mm then there is a high chance of first trimester abortion.
But it is always better to be optimistic and as i said a discrepancy of 10 % do exist as bias from a radiographer's point of view.
Regards
answered
Detailed Answer:
Mean Sac Diameter measurement is used to determine gestational age before a Crown Rump length can be clearly measured.The average sac diameter is determined by measuring the length,width and height then dividing by 3 .Once a fetal Pole can be visualised the CRL measurement is the most accurate method for dating the pregnancy.
According to books:-
Small sac size = MSD - CRL < 5mm
(15/16 patients with MSD less than 5 mm greater than CRL subsequently aborted*)
*Bromley B. Radiology 1991;178:375
If the sac size is less than 5mm then there is a high chance of first trimester abortion.
But it is always better to be optimistic and as i said a discrepancy of 10 % do exist as bias from a radiographer's point of view.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Thanks doctor. So from my scan report my MSD - CRL is more than 5mm, am I correct? I'm still trying to learn how to read from my report. Thanks!
Brief Answer:
answered
Detailed Answer:
Yes it is.
Please wait for your next ultrasound and check for the foetal heart rate. Also important is to remain stress free during early first trimester to allow better placentation and growth.
Regards
answered
Detailed Answer:
Yes it is.
Please wait for your next ultrasound and check for the foetal heart rate. Also important is to remain stress free during early first trimester to allow better placentation and growth.
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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