Rash on my thighs?

Hi am hoping one of you lovely ladies can help me. I am 7 wks 5 days pregnant and I have developed a rash right around booth my thighs. It's a raised red rash but is not itchy. It's spreading down my thighs as we speak. I have tried to look it up online but can not find anything specific? Can anyone help me? Should I be worried? X