need urgent advise

Divorceed single mother. My ex husb left and never see my child almost 3 years plus. He only provide montly mainetainance for e child. I just want to know : if your ex husb ask you for a copy of birth cert do you give him?? What are the things you dont provide a copy to your ex husb?? The reason i asked because my ex is abusive, never bother to come n see e child. What is the purpose he needs those for. I hv a sole custody. And i want to know my rights. Appeciate some advised. Thank you