We typically shed between 20 & a 100 hairs a day before we get pregnant...but it drops down to 0 to nearly none at all for the 10 months that we ARE pregnant. That's the whole glossy gorgeous pregnant hair thing. The downside is that it starts coming out practically in clumps a couple of weeks to a couple of months after our babies are born.
People with straight hair who wear it down tend to notice it less, because it can shed throughout the day...but if you have curly hair or wear it up...watchout! I used to look at the handfulls of hair in the shower and imagine chemo. Yikes. Any chance you've changed the length/how you wear it from #1 to #2?
If your hair loss seems extreme to you though, it's an easy blood test to check iron/hormones/thyroid/etc.
I'm curious though...I was told to STOP taking my prenatals when I was nursing, and while I could switch to a high calcium multivitamin, my docs recommended I really try and get everything I could from food sources. I have no idea of the prevalence of that thinking though.