He started to have more difficulties feeding her when she turned 3 months old. She would eat from the bottle only under specific conditions, such as while being bounced or held in a certain position. Then, my daughter began to refuse the bottle and cry whenever it appeared in front of her.

Instead of taking shifts, I now had the full burden of feeding as well as putting her down for all naps and bedtime, since she would sleep only after eating. I could no longer leave the house for any meaningful length of time, since she refused to breastfeed outside the house. I was exhausted, felt trapped and started to regret ever breastfeeding in the first place.

New moms are usually warned about introducing a bottle too early for fear of babies rejecting the breast for the faster-flowing bottle. But I hadn’t heard a thing about bottle refusal before experiencing it firsthand — and it was taking a toll on my mental health.

It turns out that my experience was not uncommon.

Clare Maxwell, a midwife and researcher, struggled with bottle refusal by her younger son, James.

She offered one at 12 weeks with no luck but kept trying, with a deadline looming for when she had to return to work at seven months. Maxwell bought more than 10 different brands of bottles, hoping that one would stick. She varied the milk temperature, had others attempt to feed him. Nothing worked.

“I immediately started to look for any papers on bottle refusal, or any research at all, and there was nothing,” said Maxwell, senior lecturer in Midwifery at Liverpool John Moores University in Britain.. “It was as if it didn’t exist.”

Yet, parenting forums were flooded with thousands of posts seeking help for the same issue, so Maxwell set out to investigate.

In 2020, Maxwell and her colleagues published a study on the experiences of 841 mothers whose breastfed babies would not accept a bottle. They had posted an online questionnaire to a handful of breastfeeding groups based in North West England and had to close it down after two weeks because of an overwhelming number of responses. Nearly 30 percent of mothers reported that bottle refusal had made worse their overall breastfeeding experience.

The mothers gave different reasons for introducing a bottle, such as returning to work or simply wanting to stop breastfeeding. Some women had to take exams or driving tests or attend such events as weddings or funerals.

Others had serious health-related conflicts, including needing treatment for cancer, undergoing a surgical procedure or requiring medication not safe to take while breastfeeding. Methods to try to overcome bottle refusal had a low success rate — except forcing their baby to go “cold turkey,” which can lead to dehydration.

During visits with medical professionals, over 80 percent of mothers reported they were met with a lack of helpful advice or support.

“Many health-care professionals have just shrugged their shoulders in a way that suggested I just needed to get on with it,” one respondent recalled.

Another wrote that the only advice she received “was that it was massively important to exclusively [breastfeed] and bottles were what bad mothers did. … [They] were more concerned that baby would get nipple confusion and stop feeding.”

Parents-to-be are commonly warned that exposure to artificial nipples might sabotage breastfeeding and told not to introduce a bottle before the fourth week. According to the World Health Organization’s “Ten steps to successful breastfeeding” tips, health-care providers should “Counsel mothers on the use and risks of feeding bottles, teats and pacifiers.”

But is nipple confusion real? The evidence is shaky, at best.

A 2015 review paper in the Journal of Perinatology found 14 studies that both supported and refuted nipple confusion. But none establish causality — in other words, no research exists that conclusively shows that artificial nipples are the reason some infants refuse the breast.

“At the end of the day, I don’t believe in the concept of nipple confusion,” said Emily Zimmerman, a speech-language pathologist and neuroscientist who co-wrote the paper. “The messaging [around nipple confusion] has made mothers and caregivers really stressed about adding pacifiers and bottles to their regimen.”

Zimmerman directs Northeastern University’s Speech and Neurodevelopment Lab, which studies the interplay between sucking, feeding and early infant vocal development.

As part of her research, she uses a pacifier attached to a pressure transducer system to measure an infant’s suck response pattern and how it changes in response to different stimuli. With the bottle, milk is released immediately upon sucking. With the breast, a baby must first engage in nonnutritive sucking — like the kind used with a pacifier — to trigger the mother’s let-down reflex. Once milk flows, the baby will switch to a different, nutritive suck pattern.

“Something the studies in my lab have shown is that full-term healthy babies are typically able to suck on any pacifier, bottle, nipple, breast, finger without an issue, and go back and forth,” Zimmerman said. “So the infant is able to adapt and modify.”

She also said that, in newborns, sucking starts out as a reflex controlled by the brainstem, a brain region that regulates many involuntary actions such as breathing and heartbeat even in adults.

By around age 6 months, sucking has largely transitioned to a volitional action, as a result of greater involvement by the cerebral cortex. This area of the brain plays a role in many higher-order functions, including attention, perception, awareness and thought. So bottle refusal may occur because some babies simply develop a strong preference for the breast over artificial substitutes — and they now have the means to express that preference.

But Maxwell pointed out that other babies reject the bottle in the first few weeks of life, so there isn’t one right answer. In her case, her son, James, finally accepted a bottle from Maxwell’s identical twin sister. But for the majority of mothers in her study — approximately 60 percent — nothing worked.

My daughter, now over a year old, also never took a bottle again after three months. I almost hired a postpartum doula who supposedly specialized in bottle refusal, but she wanted a $3,240 to solve the problem. And when I visited a lactation consultant, she tried to convince me that the inside of my baby’s mouth wasn’t shaped correctly and suggested that she needed occupational therapy.

Instead, at about 6 months old, I decided to just give up on bottles and exclusively breastfeed, which as a self-employed mother working from home I had the luxury of doing. I slowly ramped up her solid food intake.

Would I choose to breastfeed again, knowing what I know now? Probably yes. But with greater awareness and education around bottle refusal during pregnancy, I might have been more prepared mentally and felt less alone in my situation.

“I think health professionals avoid talking about it because they don’t know what the impact will be on mothers’ decision to breastfeed,” Maxwell said. “But we deserve to know, so that as mothers, we can make these kinds of informed choices on our own.”

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