Start of pregnancy

[ardeur]

Scientifically, do we consider fertilization or implantation the actual start of pregnancy?

[TinaDeanette]

I consider it at implantation. If that egg got fertilized but, for some reason, never implanted I wouldn't consider myself pregnant.

[ardeur]

So should your 40 weeks start at implantation?

[Kirsie]

Pregnancy dating (day 1 of your 40 weeks) begins at the start of your last menstrual period.

[TinaDeanette]

Originally Posted by ardeur So should your 40 weeks start at implantation?

No, you would just be pregnant for 38 weeks on average.

[happysmileylady]

That just depends on who you ask, and the purpose behind the question. It's really still a matter of opinion.

[Kap7270]

When they calculate fetal age (which is 38 weeks average), they do it based on conception.

My understanding is that the original OBGYN definition of pregnancy started at conception, and it was changed to implantation so that things like the pill were not considered abortion-inducing. So, yes, there are a whole bunch of moral and political implications based on how you answer that question.

[JeDeeLenae]

I also think it depends on your reasoning for that question. I don't consider myself pregnant until implantation has occurred. I am not pregnant on Day 1 of my cycle/period, but understand why it is counted when dating a pregnancy. It's much easier to date the first day of your last period than it is to date your conception, ovulation, or implantation. KWIM?

[KelseyH]

IMHO, pregnancy starts when the sperm meets the egg.

[newmommy13]

Conception happens a lot more frequently than anyone knows but implantation is what makes a pregnancy.