United Kingdom, April 14 -- Serena Williams' career comes with a "big cost" to her personal life.

The 43-year-old has been on top of the world - claiming 23 grand slam titles and becoming the world's number one women's singles player - with her tennis career, as well as becoming a successful businesswoman with her WYN Beauty make-up range.

However behind closed doors, the superstar - who has two daughters, Alexis, seven, and Adira, 18 months, with her husband Alexis Ohanian - has been battling the pros and cons of how her professional-making decisions could impact her family and relationships her "whole life".

Serena - who lives in Florida - told PEOPLE at her WYN Beauty x Shopify pop-up event in Los Angeles on April 11: "Yeah, it defi...