clomid & progesterone

I am getting ready to start my first round of Clomid for my second child....Last time I took the pills on day 3-7, this time doc says 5-9, does anyone know what the different is?  And also my prog. levels before this were 4.7, should I be on anything besides clomid to increase my progesterone?

[Tanker Chic]

From what I have read, the difference is: Typically every month you have several follicles but only one will mature.  If you start on day 5 there will usually be one or maybe two follicles that are dominant and so the clomid will work on those follicles.  If you take the clomid on cd 3-7, you are less likely to have a dominant follicle, so the clomid will work on more of the follicles and this produces excess mature follicles.  Some people think this is good because they think they have a better chance if they have a bunch of follicles.  My RE was very hard core about not producing high order multi births.  Meaning 3 or more.  Which I agree with him.  I think it is kind of reckless to take a chance on having potentially 3, 4, 5 or 6 fertilized follicles.  But really it is a personal choice.  Also depending on the person, some people will respond better on 3-7 and others with 5-9.  It is about finding what works best for you.  

As for the progesterone. You can take progesterone supplements.  I did for the first 12wks of my pg.