The progesterone suppositories definitely caused a few crampings/stretchings while I was using them, and as instructed I did a pregnancy test on day 28 and then stopped taking them. Following which my period was three, count them, three days late. Or possibly 2 if I ovulated late. Completely unheard of. And now, slightly less crampy but oddly heavier than normal. Heavier I don't mind if it's less crampy.