Hi, me question is does fidelus cover getting my tubes tied? I'm not sure and they won't answer my question.

It will really depend on your individual plan. Call the customer care helpline and talk with someone different. They will need to look at your specific policy and check your coverages and stipulations.

Each plan, and even what state ( if in the US) that you live in. Some states will require more or different coverage as a requirement to write in their state.

Your doctors should also pre authorise any medical work

In addition to the state, it also depends on whether the plan is "Fully Insured" or "Self Funded" for covered mandates. Your HR dept should be able to tell you which. If Fully Insured a little research will allow you to see what your state mandates for coverage.
Also call the carriers' customer service and ask for an EOB (Explanation of Benefits). It will explain in detail what is covered.