Can cervarix vaccination for cervical cancer effect periods cycle. Last month also I didn't got periods after first shot. Than doctor gave me medicine an than my periods came. I had my hormonal tests. Reports were normal. This month my date was 6 and today is 14. But still no bleeding .I'm having cramps. But no periods. What is it. Why my periods are not coming. I'm not pregnant also. And suddenly I got weight gain in 2 months an any my stomach also came out. I an worried. Why are such changes happening.