Gayle Tzemach Lemmon is a senior fellow at the Council on Foreign Relations. She is the author of "Ashley's War: The Untold Story of a Team of Women Soldiers on the Special Ops Battlefield." The opinions expressed in this commentary are hers.

(CNN) As they sought to help those escaping the hell of Mosul and its siege, the staff of Doctors Without Borders grappled with a huge challenge: many, many undernourished babies.

"Over the past couple of weeks we've seen an increase in the number of malnourished children needing treatment," Doctors Without Borders' Iraq country director Manuel Lannaud said in an interview released on the group's Web site.

The surprising thing is that Lannaud and his colleagues at the humanitarian aid group didn't place the blame for these underfed little ones just on war and the fact that the city was under siege. They also put the blame on other international organizations and policies that seek to do good.

"It isn't a problem of access to food. The malnutrition we see here is primarily due to the scarcity of infant formula," Lannaud wrote. "International organizations like UNICEF and the World Health Organization (WHO) promote breastfeeding ... and provide infant formula, but only by prescription. We believe that distributing infant formula in a conflict situation like Iraq is the only way to avoid children having to be hospitalized for malnutrition."

Doctors Without Borders says it agrees that breastfeeding promotion is a priority, but one that comes after dealing with the immediate crisis of a baby's survival. Says Lannaud, if mothers "need formula, we give it to them."

The mothers who need it are those facing down life-and-death situations each day, often while caring for multiple children in the shadow of war. That giving infant formula to them is so controversial speaks to a policy tripwire few outside the humanitarian realm even know exists: global "breastfeeding first" policies.

Promoting breastfeeding is a laudable goal, but in some cases, international policy ends up determining women's on-the-ground reality, even in wartime settings, rather than the other way around. In the process, policies run the risk of treating nursing mothers as children themselves, whose needs are best known by global policy makers sitting thousands of miles away, not doctors and humanitarians nearby doing their best to help.

These "breastfeeding first" policies, endorsed and enforced by well-intended humanitarian leaders such as the World Health Organization and UNICEF, present distribution of infant formula as a policy no-no that harms both mother and child, and promote exclusive breastfeeding for the first six months of a baby's life as the norm. This is the standard set out by the International Code of Marketing of Breast-milk Substitutes adopted by the World Health Assembly and the World Health Organization in 1981.

The code stipulates that there should be absolutely no promotion of breast-milk substitutes, bottles and teats to the general public; that neither health facilities nor health professionals should play a role in promoting breast-milk substitutes; and that free samples of infant formula should not be provided to pregnant women, new mothers or families.

UNICEF, which is dedicated to keeping children healthy and alive, has noted the same challenges as Doctors Without Borders, but arrived at a different conclusion. Exactly a decade ago, it issued a paper saying that "exclusive breastfeeding is the single most powerful means of protecting the health of Iraqi babies during this time of crisis."

As UNICEF Senior Nutrition Adviser Vilma Tyler told me, "UNICEF is all about ensuring that we provide the right form of protection and the right response in an emergency. When it comes to nutrition of course based on a lot of research over the years and a lot of evidence that exclusive breastfeeding is the beast nutrition for a child for the first six months." Asked if there is some room when it comes to their policy, Tyler said, "We recognize at the same time that children have been separated or mothers are not able to breastfeed for many reasons so we work closely with the government to ensure ... the best intervention."

As it does today, UNICEF warned a decade ago that Iraq's policy of distributing infant formula free could be a "recipe for disaster in current conditions," particularly if that formula was prepared with unsafe water, which is all around in crisis zones. (Premixed formula can be useful in these settings, though it is often harder to find than powder.) And it is indeed true that unsafe water and unclean utensils -- both of which can be found in abundance in crisis situations -- can place babies' lives at risk. It was, in fact, a 1970s expose about the aggressive marketing of expensive formula to create dependency among mothers in the developing world that helped lead to the International Code's 1981 adoption.

For their part, WHO officials say breastfeeding policies are there to save babies' lives and keep children safe. But they stress that an examination of what is happening on the ground is crucial.

"Breastfeeding is the best option, especially in emergency settings, but I would emphasize that there are infants who need formula, and then everything should be done to improve access to those infants," Dr. Zita Weise Prinzo, who is part of WHO's Nutrition in Emergencies program, told me.

"There is no clear right or wrong; one has to do an assessment and see the recommendations are followed through."

Yet for aid workers, the question remains, what to do when women come seeking formula? And what about meeting women's needs when stresses are extreme and resources finite? Breastfeeding on the move, in stressful circumstances, while displaced, underfed themselves or working to keep other children alive and healthy may prove difficult for mothers working simply to endure daily life amid war.

"Emergencies often lead to displacement. It may be difficult for mothers to find comfortable, private places to breastfeed," noted Dr. Francesco Branca, the WHO director of nutrition for health, and Werner Schultink, UNICEF's chief of nutrition, last year in a joint commentary on the importance of breastfeeding in emergencies. "Humanitarian organizations must protect, promote, and support breastfeeding in emergencies. Policies need to be in place that prohibit the donation of breast-milk substitutes and control their procurement and distribution in emergencies, based on appropriate needs assessments...multiple communication channels are needed to reach mothers and their family members with messages on the importance of continued breastfeeding and the dangers of using breast-milk substitutes."

For those on the front line, like MSF's Lannaud, however, it is hardly so cut and dried.

Follow CNN Opinion Join us on Twitter and Facebook

"This is a debate we have ourselves: you meet all these stressed-out mothers and what are you supposed to do?" one aid worker based in the Middle East and focused on the Syria crisis told me. This aid worker talks of the increase in emergencies and the number of traumatized and shocked mothers seen all around. "The idea behind the policy is a good one, but is this policy still relevant? Or is there room to be a bit more flexible?"

Sometimes, says this aid worker, "I think, oh, my God, why can't we just give formula?"