"Spine, somewhere in this region," the tennis pro continued matter of factly, documenting the little one's body parts on her black Nike pullover. "You have the feet maybe over here or a little bit over here. Hands, I feel it punching, are over here."
The mama-to-be concluded the clip with a mini pep talk for her baby, stating, "Be focused when you come out. You want to slide out."
Williams, who is due in early September, has kept cravings pretty healthy, preferring zucchini, asparagus and artichoke over sweets and strange food combinations.
For more on the tennis star's pregnancy, watch the video below.