What Causes Delayed Periods After Copper Coil Removal?

Hi i seem to have stopped having periods for no reason, my doctor has done an ultrasound and an internal scan and everything was fine and also had all my hormones tested along with fbc and thyroid function, everything was fine but no periods, im not pregnant but me and my husband would like baby no 2. If it helps i had a copper coil about 6 months ago but had it removed 6 weeks after due to periods stopping