Sleep Training: Misinformation, Misunderstanding, and Missed Opportunities

Photo from Flickr, David J. LaPorte.

Photo from Flickr, David J. LaPorte.

An article about sleep training was recently published online written by Stephanie Liu, a mother and a physician. It sparked a lot of interest when I initially posted it on social media in early April. I’d like to delve into the information (and issues) that are in the article. The article was published in on March 28, 2019 with the title “Why Sleep Training Won’t Hurt Your Baby”. Because there is quite a lot to unpack in Stephanie Liu’s article, I’m focusing today on why accurate reporting of science matters, and why it can be difficult to get. I’ll focus at another time on the science she uses to back up her argument for why sleep training is a good idea.

I want to start by emphasizing that my critique of the information in this article is not intended, in any way, to minimize the experience of the author. The fatigue, struggle, and overwhelm that she reports is likely recognizable to most of us with very young children. The uncertainty we feel in balancing out our preconceived notions of motherhood, with the information (both cultural and research-based) that we are bombarded with in social media, through friends and family, and through our queries to health care professionals can feel unsolvable. Also recognizable will be the conflict we feel as moms when our instincts and our inclinations don’t match with what we read in the literature and what we’ve been taught.

One concern I have with the article that as a physician, Stephanie’s words and use of science must be particularly careful to be accurate and accountable. Backing up her personal decisions to cry it out with science references is fine; but her use of research leaves out credible information that contradicts her interpretation. It would leave many tired moms with the impression that if this mom and physician can site two articles that suggest cry it out does no harm, then it must indeed be true. Unfortunately, it is not quite that simple: we must look deeper at what the studies are actually showing us to more fully understand why there seems to be a contradiction in the research around whether harm is caused by crying it out or not. Two studies are not nearly the whole story, and the difficulty in measuring outcomes is one of the main reasons that sleep training remains such a hotly contested approach.

Just as important is what perspective we are taking when we try to measure outcomes from sleep training. If a researcher’s goal is to teach independent sleep, their measures of success will look quite different than those researchers whose goals are to support biologically normal infant sleep development (which includes independent sleep, but not before babies are developmentally ready).

There can be a big clashing of mind and heart when what we feel is right contradicts what our head says is fact.

T]here can be a big clashing of mind and heart when what we feel is right contradicts what our head says is fact. Stephanie’s comments that “I couldn’t stand hearing my baby cry herself to sleep” will resonate with those of us who have felt compelled to try “cry it out”. So too might her comment that “as a physician I also knew that… [sleep training was safe]”. Mind and heart —intellect and instinct— at odds with each other. For me, motherhood was the first time I had truly experienced that conflict, and as an academic-minded, literature-loving health care professional who’d never much had to rely on what my heart felt, it was a very tricky conflict indeed.

In the coming weeks, I will review each the research papers Stephanie mentions. I will critique them, and put the evidence in context of biologically-based, ecologically-oriented expectations around infant sleep development. In essence, I am putting my mind and heart into this. I have reached a point in my mothering and in my career where I can now look at the contradictions in the literature —the conflicting information, the mis-interpretation, and the research perspective— in a way I could not possibly have done in the early days of parenting. I have some hindsight now. My mind remains open to dissenting information, and articles that contradict each other. But my mind is also aware of the difficulties in interpreting data, and relaying that information, and then applying it to the lived experience of motherhood and babyhood. My mind and my heart are no longer on opposite sides.

The issue of supporting infant and child sleep is a complex one, and one that also includes supporting moms: their well being, their mental health, their concerns, and their aspirations. Looking at infant sleep in a vacuum, without appreciating the complex social and cultural pressures that are placed on mothers, means a missed opportunity to find nurturing and biologically-normal ways of supporting development of independent sleep while simultaneously supporting under-nurtured and over-tired mothers.

I will say again that I have carefully avoided contradicting the author’s particular opinions and judging her personal experiences: although as moms we can relate to each others’ experiences, our experiences are ours alone; the perceptions we have of our experiences change over time as we gain context, and as time fades the wounds of motherhood guilt and worry in the early days.

Most studies are a tiny slice of the pie we call “understanding” and, as such, one paper rarely gives us the broad, definitive answer we are looking for…

I’d like to talk about the title of Stephanie’s article: “Sleep Training Will Not Harm Your Child”. It’s possible that title is as much (or more) the editor’s choice than it is the author’s, and reflects the controversy over sleep training: it garners attention and increases readership, but at the expense of accuracy. Studies on sleep training (which, to begin with, is not a term that is consistently defined across articles and literature) have particular scopes, specific ways of measuring outcomes, and narrow questions they are trying to answer. Most studies are a tiny slice of the pie we call “understanding” and, as such, one paper rarely gives us the broad, definitive answer we are looking for in answering the question “what is the best way to support babies’ sleep?”. Perhaps it makes more sense to ask “what is the best way to support my baby’s sleep?”, since each of our little ones are unique individuals, with particular needs, temperaments, and development. And our children are in unique environments, with unique family strengths and risk factors. There is no right answer. There may be a more right answer. And there may be more than one right answer. But science progresses, and good science acknowledges its limits in figuring out what those right answers might be.

How do we answer the question “what is the best way to support babies’ sleep? Perhaps it makes more sense to ask “what is the best way to support my baby’s sleep?”

One of the challenges in applying the science on infant sleep to individual babies is the tendency for some health care providers (based on my personal experiences and what families share with me) to ask about sleep (good!), and then to recommend sleep training if an infant is not sleeping through the night when some researchers say they ought to.

There are a few problems with that. When we measure consolidated sleep and sleeping through the night, we need to know:

  • how sleep develops,

  • how babies are physically able to stay asleep; and

  • how babies develop self-regulation (Henderson et al., 2010).

These are developmental and physiological issues, not learning issues. And yet the temptation is to take what we know about typical sleep and suggest forced learning for babies who are not meeting ‘criteria’ at a particular age.

Instead, we ought to be appreciating that:

  • ‘average’ is a statistic. It does not apply to individual babies

  • babies who are not average may be doing absolutely fine (some of whom will consolidate sleep earlier than average, and some who will consolidate sleep later than average), and

  • for those babies who are having difficulty consolidating sleep at an age when we expect them to, families may need help figuring out what is getting in the way, rather than trying to change a baby’s behaviour through sleep training.

“If we can’t force normal infant sleep development to occur before a baby is ready, then how do we support moms during this intense and exhausting time?”

By focusing on the questions “what, if anything, is getting in the way of sleep development?” and “how can we support development of sleep?” the focus becomes less about a problem that may not be a problem at all (for baby, anyway), and more about natural skill development. I will add a third very important question we need to ask: “If we can’t force normal infant sleep development to occur before a baby is ready, then how do we support moms during this intense and exhausting time?”.

Therein lies the art and science of infant sleep.

Next week I will review an article by Henderson (2010) that Stephanie Liu cites regarding when babies are expected to sleep through the night.



Henderson, J.M., France, K.G., Owens, J.L., & Blampied, N.M (2010). Sleeping through the night: The consolidation of self-regulated sleep across the first year of life. Pediatrics 126 (5). Accessed online June 14 2019.