What Causes Groin Joint Pain And Difficulty Sitting In Padmasana Pose, Especially Considering My History Of Sciatica During Pregnancy?

I am a 39 year old female.I am overweight.Height is 163 cm and weight is 75 kg.I have pain in my groin joints .Have difficulty sitting in padmasana pose or it becomes painful if I sit on bike with legs on both sides.During pregnancy 8 years back I had sciatica issue as well.What could be the cause of this?