What is this rash?

I have had a very itchy rash at the top of my legs near to the groin area for about 5 years.  While I was pregnant the rash totally cleared up but came back after about 6 weeks.  It also seems to get worse the week before my monthly period is due.  Would appreciate it if someone could tell me what this is and what treatment would be suitable.

[Dr_Aparna]

Hi,
The most common type of rash at the groin would be a fungal infection.Tinea cruris is the scientific name for fungal infection of the groin region.
It causes itching or a burning sensation in the groin area, thigh skin folds, or anus.
Affected areas may appear red, tan, or brown, with flaking, peeling, or cracking skin.
A warm, damp environment allowing the fungus to cultivate greatly contributes; especially with tight, sweaty or rubbing clothing.
Tinea cruris is best treated with antifungal drugs applied topically. Traditionally creams containing tolnaftate, clotrimazole or miconazole have been used, although newer agents such as butenafine are also used.
ref:http://en.wikipedia.org/wiki/Tinea_cruris