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Date of last update: 10/14/2017.

Forum Name: Gynecology

Question: Date conceived from scan results

 peanuts123 - Mon Mar 30, 2009 6:40 am

Hello Doctor,
I had my scan today and as on 30th march 2009 the scan said I am 5weeks 4days Pregnant.
My First day of last s it possible to calculate the date I conceived from the above information? If so, are my ovulation day and conceived day same?
I just want to calculate the exact day I ovulated and exact day I conceived.

Thank you very much
 Debbie Miller, RN - Sat Apr 04, 2009 5:35 pm

User avatar Hello,
It is impossible to say the exact day of conception or ovulation as these vary with the individual. Most women ovulate sometimes during about a 12 day period. Depending on when you had sex, conception can take place at the time of ovulation but sperm may have been present for 3-5 days, still living, when the egg is released so exact time of conception is not necessarily date of sexual encounter.

I would guess conception was about March 6, based on the dating by scan. Once you ovulate, the egg has only about 12 hours to be fertilized so chances are conception occurred the same day as ovulation. I hope this helps.

Best wishes.
 peanuts123 - Tue Apr 07, 2009 11:55 am

Thank you doctor.
usually my calculations match.
May be my cycle is not yet regulated. My first period after lactation was in December.

Well, I still am confused. My question didn't have my last period date. Did you edit it or somehow that missed when I posted.

Is there any safe way to follow Natural prevention method without extensive training?
 Debbie Miller, RN - Wed Apr 08, 2009 12:28 pm

User avatar Hello,
We don't edit your post unless you duplicate and post twice so you must have left it out.

I guess I'm a little confused here too. You are pregnant now. Near as I can tell you probably conceived about March 6 based on the scan results. However you could have had sex up to five days before that to result in that conception date.

As for natural family planning, I assume you're talking about next time. There are reliable methods, especially if you are regular with your cycle. If you have a 26 to 32 day cycle, a good method is cycle beads. This is a visual reminder (beads) that you can keep handy to monitor which day in your cycle you are on. When you reach the different colored beads (as you track them with a sliding O ring), you know you are potentially fertile. This is about a 12 day spread but we don't know which day you actually ovulate so you would avoid having sexual intercourse on those days, resuming when the bead color changes again. Or, you may choose to use additional protection such as condoms during the fertile days.

Another method is called the two day method and it relies on you being in tune with your body's secretions which change during ovulation. If you have increased secretions (kind of like egg yolk) that you can feel with your fingers, you should not have sex. The two days means, if you had secretions yesterday or today, this is not a safe time for sex if you wish to avoid pregnancy. Once you have been two days without the secretions, that would be a safe time. Some women, with practice, become very attuned to their body's secretion patterns and can predict their ovulation quite accurately. These methods are not perfect, but they do not use any hormones that sometimes have unpleasant side effects or risks and when used properly can be as effective as other methods of family planning.

I hope this helps.

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