Hello and thanks for your post,

There is no current scientific evidence to link having an underactive thyroid and ovarian cancer. These are two very different medical conditions. Although it is possible to have both medical conditions at the same time. 

We have information on the risks and causes of ovarian cancer on our website link here,

https://www.cancerresearchuk.org/about-cancer/ovarian-cancer/risks-causes

I hope that is helpful, 

Best wishes,

Vanda