Leaving in front of other services, the Pinterest decided no longer to limit gender choice in the profiles of its users. Now, besides "male" and "female", you can customize the gender box with whatever you want.
To change, just enter the account settings and select "Personalized" in the "Sex" section. A box will be opened to enter the genre of your preference.

Whether male or female doesn't suit you, now you have a new option. You can put an emoji in place, too.
↪ Source: Pinterest Blog