Leg colouring...?

Anyone else experienced something like this? I have had it on both legs for about a month now. Some days it’s worse than others and if I’ve had a hot shower it disappears or reduces/turns red. This makes me think it might be a circulation thing. My legs have certainly gotten a lot fatter during the pregnancy- probably the only place I’ve put on weight. I spoke to my midwife a couple of weeks ago about it and she said it could be stretch marks but I don’t think so...