A human female is born with a finite number of oocytes, estimated to be around 1 to 2 million. However, this number decreases over time and only a small fraction of these oocytes will ever mature.

Here's a breakdown:

* At birth: A female has around 1-2 million oocytes.

* Puberty: This number has decreased to around 300,000.

* Throughout reproductive life: Only around 400 oocytes will mature and be released during ovulation.

So, while the total number of oocytes at birth is large, the number that actually mature and have the potential for fertilization is significantly smaller.