Can girls get pregeant if they before they start their period? I'm not at all asking from a sex-ed point of view, i'm asking from a biological point of view. I mean, when girls menstrate, their chromosomes repliciate when replacing the eggs, right? And to get pregeant, sperm matches with the egg, however, if you haven't had your period, then you wouldn't have replicated versions of your genetic code?

no duh.....

Can girls get pregeant if they before they start their period? I'm not at all asking from a sex-ed point of view, i'm asking from a biological point of view. I mean, when girls menstrate, their chromosomes repliciate when replacing the eggs, right? And to get pregeant, sperm matches with the egg, however, if you haven't had your period, then you wouldn't have replicated versions of your genetic code?

The period (menstruation) is the sluffing off of the lining of the uterus, because an egg — which has been ovulated previously — has not been fertilized by a sperm. The extra uterine material — which is there to nourish a fertilized egg that implants itself — is no longer needed.

At birth, girls have all the eggs (undeveloped) in their ovaries that they will ever have, about 200,000 to 400,000 in each ovary. Most of them deteriorate before menarche (first menstruation), leaving only a few hundred. All these "replicated versions of your genetic code" are in the girl's ovaries before menarche.

So, rather than " no duh.....," it is possible to get pregnant before the first menstruation (menarche), although it is unlikely.

Any one unprotected sexual intercourse typically has a 5% probability of resulting in pregnancy. Of course, for repeated, unprotected sexual intercourse, the odds for pregnancy increase considerably.

I hope this helps you both understand the process a little better. Thanks for asking.