Hello and welcome, I pill is meant to be used occasionally after unprecedented acts of sex. There is no literature to show its long term effects on fertility after constant use as it is not meant to be used in that way. However you may be having some other problem that may be causing a delay in periods like hormonal imbalances [ especially thyroid or prolactin] or ovarian cysts. I do not think that I pill will lead to such issues as its effects are transient and it does not remain in the system for so long. I suggest that you see a doctor and get examined as well as tested for these issues. If there is a problem then you can get treated for the same. Hope this satisfies your query. Thanks for using HCM. Feel free to ask any more questions that you may have. Dr Madhuri Bagde Consultant Obstetrician and Gynecologist