It comes down to the definition of "medical condition." The Pregnancy Discrimination Act, an amendment to Title VII, prohibits discrimination based on "pregnancy, childbirth, or related medical conditions." Lactation is none of these, a federal district court held last year, granting summary judgment to the employer. See our post of that decision here.
Reversing that decision, the Fifth Circuit Court of Appeals has held that lactation is a "medical condition" for purposes of the PDA. Noting that a medical dictionary definition of "medical condition" includes a "physiological condition," the Court said that "it is difficult to see how [the definition of "medical condition'} could not encompass lactation." EEOC v. Houston Funding II, Ltd (5th Cir. May 30, 2013).
The EEOC alleged the employer had fired the plaintiff because she wanted to pump breast milk at work. The case was remanded to the district court.