A photograph showing two soldiers nursing their children has caused another round of breastfeeding controversy.

Terran Echegoyen McCabe And Christina Luna are member of the U.S. Air Force.

Rules while in uniform

There are a lot of things you are not allowed to do in military uniform -- including eating or talking on a cell phone while walking, keeping your hands in your pockets, chewing gum, holding hands, kissing and hugging (except during homecomings and deployments) -- according to a list of 11 such restrictions on the website of Veterans United. Soldiers are also expected to always have their right hand free so they may salute at any moment. There are no official rules when it comes to breastfeeding.

--Military moms Terran Echegoyen McCabe And Christina Luna are shown breastfeeding while in uniform

The photographs, which are part of a breastfeeding awareness campaign launched by the Mom2Mom support group on the Fairchild Air Force Base, in the state of Washington, are being seen by some as a challenge to unwritten ones.

In an interview with the "Today Show", Air National Guard member Terran Echegoyen McCabe, who is shown nursing her 10-month-old twin daughters, said that the act of breastfeeding in uniform was not new -- she does it all the time, she said, "in our lobby, in my car, in the park. I'm proud to be wearing a uniform while breastfeeding. I'm proud of the photo and I hope it encourages other women to know they can breastfeed whether they're active duty, guard or civilian."

Recent controversy

This controversy comes shortly after Time Magazine featured a mother breastfeeding her 3-year-old son.

Jamie Lynne Grumet, 26, was one of four mothers photographed for the piece on the parenting approach heralded by Dr. Bill Sears in his 1992 book that recommends extended breastfeeding, co-sleeping and baby wearing. The May 21 cover asks, "Are You Mom Enough?"

Click here to watch an interview with Grumet

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