The uterus point in reflexology is located on the inside ankle about halfway between the ankle bone (malleolus) and the heel. On a non-pregnant foot there is a natural indentation there, on the pregnant foot it is puffy and soft. Gentle rotations over this area may help to relax the uterus and give labor a nudge in the right direction. Deep pressure here is not advised.
This won't replace a labor/maternity session with a professional reflexologist but it might help with braxton hicks or slow prelabor.
Hope this helps!