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How To Determine The Date Of Conception?
Question: Hey Doctor, I have a question regarding an Ultrasound scan . I have a picture of a USG scan that was taken on XXXXXXX 2,2016 and it stated that the embryo was 8 weeks and 1 day of age. Now there is Also a date on the scan of April 6,2016. Could this April date be the date the female actually conceived or is that the date of her LMP? Those are the only dates mentioned on the scan.
Brief Answer:
LMP
Detailed Answer:
Dear XXXXXXX
By ultrasonography, usually it is not possible to exactly predict the date of actual conception. No doctor mentions the date of conception on the plate. The date mentioned should be the date of Last Menstrual Period (LMP). Usually, there is a custom of writing LMP with the date.
However, you may consult the ultrasonologist to get it confirmed.
For any more information, I am always available for you, XXXXXXX
Dr. Nishikant Shrotri
LMP
Detailed Answer:
Dear XXXXXXX
By ultrasonography, usually it is not possible to exactly predict the date of actual conception. No doctor mentions the date of conception on the plate. The date mentioned should be the date of Last Menstrual Period (LMP). Usually, there is a custom of writing LMP with the date.
However, you may consult the ultrasonologist to get it confirmed.
For any more information, I am always available for you, XXXXXXX
Dr. Nishikant Shrotri
Above answer was peer-reviewed by :
Dr. Vaishalee Punj
Hey Doctor I have an extended question for you regarding a Conception situation. I had sex with a girl on March 18,2016 and April 5 2016 which was the day before the start of her LMP. She had an ultrasound done on XXXXXXX 2 2016 which stated she was 8 weeks and 1 day pregnant. She also mentioned that she had been having sex with another guy around April 18-27 of 2016,but said she had protected sex with him and they only had sex ONE TIME!! however I don't know If that's true. Can you explain to me what are the chances she was conceived . I am unsure if she got pregnant by me or the other guy. I use the pull out method but I don't know if that was enough . Also she is saying her doctor said she got pregnant the week of her LMP is that true? From my understanding , the fetal age is usually 2 weeks less than her gestational age. If this is true how can this possibly be my child if we only had sex the day before her LMP which was April 5,2016. She also said the doctor gave her the expected due date of January 11,2017(40 weeks) . Overall based on all the information given what could have possibly happen wrong in the ultrasound scan and or the information given for her to believe the child is mines and not someone else. I am basically asking what are the chances this could be my child based on the facts of the information given in the scan and what's is given in the discussion. Can the fetal age and gestational age be the same or that close in the week? Have you heard of any special cases where this could be possible? I need to ensure that I am not the father of the child? Also I was researching about ovulating periods and found out that most ovulation can occur 11-21 after the first day of the menstrual cycle or 12-16 days before the next expected period.
Brief Answer:
Itercourses before LMP cannot cause pregnancy
Detailed Answer:
Dear XXXXXXX
You seem to be quite concerned about the paternity issue of the baby your girlfriend is carrying. There are multiple points which are worrying you on this issue. So me tackle each of them one by one.
1. You should not rely on pull out technique as a contraceptive method. Even though you withdraw penis before ejaculation, you have not prevented the deposition of pre-seminal secretions (precum) which gets expelled out much before ejaculation; and this is without any sensation. Precum does consist of sperms in it which are capable of causing a pregnancy.
2. However, for practical purposes, there is a very remote (almost no) possibility of conception by an intercourse on day prior to the menstruation. So you may rule out this possibility. However, 18th March does fall very near the egg release and can cause a pregnancy. Egg release (ovulation) is 14 days prior to the next expected menses. Egg has life of 24 hours while the sperms are active for 3 days. Hence a period of about a week around the day of ovulation is fertile window. You did have intercourse in this fertile window. However, since she had her menses on April 5 and both your intercourses were before that, they cannot be responsible for her pregnancy.
3. Estimated age of gestation in early pregnancies may have error of variation of few days. So please do not stick to these days rigidly.
4. If the expected due date is January 11 (based on LMP), her LMP should be April 5. Considering her menses regularity of 28 days, the date of egg release would be 19 April. She had intercourse on 18 April with another guy. So this intercourse is most likely to be responsible for the pregnancy.
5. Now if still you have got a doubt about the paternity of the child since your girlfriend had sexual relations with some other person; the best and fool proof way for confirmation is going for DNA test.
I am sure this has clarified all the doubts about the situation and you will graciously post a good review with 5 stars rating for me.
For any more explanation of doubt, please feel free to ask me anytime.
Dr. Nishikant Shrotri
Itercourses before LMP cannot cause pregnancy
Detailed Answer:
Dear XXXXXXX
You seem to be quite concerned about the paternity issue of the baby your girlfriend is carrying. There are multiple points which are worrying you on this issue. So me tackle each of them one by one.
1. You should not rely on pull out technique as a contraceptive method. Even though you withdraw penis before ejaculation, you have not prevented the deposition of pre-seminal secretions (precum) which gets expelled out much before ejaculation; and this is without any sensation. Precum does consist of sperms in it which are capable of causing a pregnancy.
2. However, for practical purposes, there is a very remote (almost no) possibility of conception by an intercourse on day prior to the menstruation. So you may rule out this possibility. However, 18th March does fall very near the egg release and can cause a pregnancy. Egg release (ovulation) is 14 days prior to the next expected menses. Egg has life of 24 hours while the sperms are active for 3 days. Hence a period of about a week around the day of ovulation is fertile window. You did have intercourse in this fertile window. However, since she had her menses on April 5 and both your intercourses were before that, they cannot be responsible for her pregnancy.
3. Estimated age of gestation in early pregnancies may have error of variation of few days. So please do not stick to these days rigidly.
4. If the expected due date is January 11 (based on LMP), her LMP should be April 5. Considering her menses regularity of 28 days, the date of egg release would be 19 April. She had intercourse on 18 April with another guy. So this intercourse is most likely to be responsible for the pregnancy.
5. Now if still you have got a doubt about the paternity of the child since your girlfriend had sexual relations with some other person; the best and fool proof way for confirmation is going for DNA test.
I am sure this has clarified all the doubts about the situation and you will graciously post a good review with 5 stars rating for me.
For any more explanation of doubt, please feel free to ask me anytime.
Dr. Nishikant Shrotri
Note: Revert back with your gynae reports to get a clear medical analysis by our expert Gynecologic Oncologist. Click here.
Above answer was peer-reviewed by :
Dr. Nagamani Ng
Answered by
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