All over the country right now, working mothers of young children are in their offices, cubicles, break rooms, parked cars, or other spot in their workplace, pumping breast milk for later use. However, flight attendants for Frontier Airlines say they have been barred from pumping while on the clock.

In complaints filed with the U.S. Equal Employment Opportunity Commission, two Frontier flight attendants detail how they allege the carrier denied their requests for accommodation of their need to express breast milk, which they say is forcing them to choose between their job and their children.

One attendant, who has worked with Frontier since 2004, gave birth in 2015 and returned to the job when her child was four months old. Since her baby still exclusively consuming breast milk at the time, the flight attendant needed to pump milk every three or four hours.

“Because Frontier has no policy for flight attendants who need to pump breast milk, I was obligated from April 2016 through December 2016 to use a pump to express breast milk in the family bathroom at Denver International Airport and in the lavatory on board the aircraft at an appropriate time in between my active duties,” she writes [PDF].

She claims that when she asked the airline for a non-bathroom solution, she was told she could take an unpaid leave of absence. The airline also allegedly told her that pumping breast milk while she worked on a plane was out of the question, meaning that even her use of the plane lavatory was not allowed. Additionally, her complaint states that Frontier would not allow her to work on shorter flights that would allow her to pump while not in the air. Without any other option, she took the unpaid leave.

The second flight attendant has been with Frontier for 11 years, and gave birth to her son in May 2016. When she returned to work three months later she said that the airline denied her request that she be temporarily assigned to a non-flying job. Similar to the other EEOC complaint, this Frontier attendant says [PDF] the airline’s only offer was unpaid leave, which she took.

Both complaints argue that Frontier is discriminating specifically against women, claiming that the airline has other policies — job restructuring, modified work schedules, reassignment — for employees with disabilities that make it difficult or impossible for them to perform their current job.

The flight attendants also note that even though the airline “does not police flight attendants’ breaks or use of the restroom while on duty to take care of other physiological needs,” it explicitly stated that pumping breast milk in the plane restroom is forbidden.

This is particularly problematic for attendants who can work 10 to 12 hours a day. The attendants do concede that Frontier has established some “designation lactation rooms” at airports to be used by employees during the brief intervals between flights, however, they point out that flight attendants are supposed to arrive at a departing plane 45 minutes before it leaves the gate, giving them little to no time to attend to their nursing needs.

By filing these complaints with EEOC, the flight attendants say they hope to compel Frontier to make several changes for their pregnant and breastfeeding employees. These include providing clean and convenient accommodations for pumping while on duty, even when it’s on a plane; allowing affected employees to be temporarily reassigned to terrestrial jobs so they don’t have to pump breast milk several thousand feet in the sky; and establishing a concrete and useful maternity leave policy.

In a statement to the Associated Press, Frontier says, “We have made good-faith efforts to identity and provide rooms and other secure locations for use by breast-feeding flight attendants during their duty travel.”

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