Can I take progesterone without a Dr telling me to?

Hi. I have a question about taking progesterone. My husband and I have been trying to conceive for the past 20 months. This month we have already started the Gonal F to go with an IUI (sometime this week - I'll find out more tomorrow) Anyways, I asked my regular Dr about getting my progesterone levels checked, just to be sure, and he said that progesterone has nothing to do with getting and or staying pregnant. <-- Even tho I argued with him - but I guess he's a Dr, and knows all? hehehe
Anyways, I plan on asking our Fertility Dr tomorrow as well, but thought I'd get you opinions first.
Just to be sure, can I just take the progesterone cream myself, a couple days after the HCG trigger shot? Is there any harm in doing it myself, without a Dr saying to? It could be that my progesterone levels are low or something and thats part of the reason we havent coneived yet!?
Thanks for everyones advice.

Thank you ladies so much for your advice. I thought the regular Dr was a quack too - now I know it's not just me.
I'll be sure to talk to my fertility Dr tomorrow when I got for another internal ultrasound, and hopefully he'll be able to answer my questions.
Thanks again.
Baby dust to all who are trying.

Your DR sounds like they don't know much about the ttc process. Good thing you have a specialist. Anyway I don't recommend taking it with out being told because if this is not the problem then if you take it it could cause a problem like m/c. Make sure you ask your RE to test your levels. Happy Baby Dust to All :)

Progesterone has everything to do with getting and staying pregnant....What kind of Doctor is this???? My friend has been trying to get pregnant and hasn't in 12 months.She just found out she isn't producing enough prog.She is now on medication to bring up her levels.You could read up on the cremes and try it out yourself.But I would get another Doctor on board and come up with a plan.

Your regular doctor is an ob/gyn and told you that progesterone has nothing to do with getting and/or staying pregnant? I'd find a new doctor, hon.

Progesterone creme allows only the smallest amount of progesterone in your system. Many women swear by it. I don't see it as a problem if you use it, although I am not convinced there is adequate progesterone making its way to your bloodstream to make any difference, even if your levels are low unless you are slathering it on.

I would also like to tell you that there are also quacks out there with bona fide medical degrees. They could have been the bottom of the class for all you know. It's one thing to be a doctor and have differing ideas than the popular treatments of the day, but he should BACK IT UP. I would add that despite THREE studies, many non-fertility doctors continue to believe that most miscarriages are caused by genetic malformations, when in fact, this has only been proven in 40% of cases. 60% of the time, there is another cause for a miscarriage.