Monday, 12 May 2008

Concerns about "bag slings"

Potential Dangers of Bag Slings

With the majority of fabric carriers it takes only a few minor adjustments to get baby safely and comfortably positioned (see the article "Correct Positioning") however, it appears that ‘bag slings’ have several significant design flaws that could place an infant at risk of respiratory distress or oxygen deprivation.

First, bag slings are roughly triangle shaped; flat bottom and two sides that slant upwards toward the elastic top. This “triangle” means that the pouch fabric is always angled very close to the sides of baby’s face. If baby rotates even slightly he ends up with his nose within a ¼” of the side, or even pressed against the side of the pouch. Once baby has his head pressed against the side of the carrier and/or against the parent's body there is a risk of him becoming oxygen deprived or even suffocating.

Second, it is difficult for the parent to closely monitor their infant unless the top of the sling is pulled open. Bag slings are generally deep, plus they sag when baby is placed in it, further increasing the depth of the carrier. The gathered top, and the fact that the sling hangs so low, obstructs the parent’s view of baby. If a newborn were to have difficulty breathing, and/or rotate until his nose and mouth was pressed against the side of the carrier, the parent may not be aware of the baby’s respiratory distress for some time. Compounding this problem is the difficulty of feeling the baby's distress through the thick fabric of the sling.

Third, although there are bag slings designed with large mesh panels placed near the infant’s head, others are not. There is a possibility that, with only a very small opening at the top of a non-mesh sling, an infant may not receive an adequate amount of fresh air. There is the concern that carbon dioxide levels could rise the longer the infant remains in the sling.

For more information on the dangers of re-breathing see this article:

“About Carbon Dioxide Poisoning and SIDS”

Fourth, the design of a bag sling causes baby to curl chin to chest, larger babies more so because their heads are positioned further up in the carrier. This position kinks baby's airway causing the baby to work harder to breathe.

Additional bag sling photos on these manufacturer websites:



Boppy Carry in Comfort

Lamaze Close Comfort (no longer in production)

For more information on the importance of maintaining an infant's head and neck in an aligned position see the articles:

"Baby car seat 'cot death' concerns"

"Simple Car Seat Insert to Prevent Upper Airway Narrowing"

PEDIATRICS Vol. 112 No. 4 October 2003, pp. 907-913

Compare bag slings with a shallow fabric pouch or adjustable open-tailed sling (or mei tai or wrap). In these types of carriers an infant is easily monitored. Also, a newborn's head is effectively sandwiched between the sides of these carriers, preventing the infant from easily rotating his head into the sides of the carrier.

M’Liss Stelzer

Registered Nurse,

Now babywearing educator and mother of two

Bag Sling Testing


Charlie was born 6 weeks early, at 34 weeks, and, due to respiratory difficulty he spent time in the Newborn Intensive Care Unit. He is now 2 months old (3 weeks corrected gestational age) and approximately 9 lbs. According to his parents he does not have any respiratory problems although he apparently has mild reflux. Mom says that after his feedings she spends an hour holding him upright because, if she puts him down flat, he spits up his feeding.

His saturations in mom’s arms averaged 94 – 98%.

Charlie’s parents wanted me to check his saturations in an Infantino sling. Dad has been using this sling however Mom doesn’t because the few times she used it the sling hurt her back, plus she was worried Charlie couldn’t breathe well. She said she always kept one arm under Charlie to support him in the sling. Dad was apparently more comfortable using the Infantino. He said it doesn’t hurt his back and Charlie appeared content and comfortable. He had not been using the lower body harness because Charlie didn’t like it. Dad said even with the lower body harness Charlie would turn toward his body and he seemed to do fine in that position.

Dad put the Infantino down on the couch, spread it open and placed Charlie in the sling the way he was accustomed to wear it. (Per Infantino’s instructions baby should never be placed in the sling while the parent is wearing it. The sling should always be placed on a firm surface, baby secured and then the sling, with baby in it, is slipped over the parent’s body.)

Charlie was curled in the sling with his face pressed against Dad’s body. His saturations were 94 – 96% and, after a couple minutes in the sling, I checked his respiratory rate and it was 56. (Most newborns average a rate of 40 to 48.) Dad volunteered to hold the pulse oximeter and monitor it while I talked to Mom about other carrier options.

Charlie was in the Infantino for 10 to 15 minutes (saturations remained in the 90’s the entire time) when I heard him grunting with every breath.

Me: “He’s grunting.”
Mom: (confused look on her face) “No, he just does that sometimes.”
Me: “Just in the sling or other places?”
Mom: “Well, mainly in there (gesturing at the sling) but sometimes in his crib.”
Me: “No, he’s grunting.” As grunting noises continue with every breath. **

At this point Dad had his arm under Charlie and shifted him slightly. (I didn’t think of it at the time but I would have liked to check Charlie’s respiratory rate before Dad moved Charlie in the sling. From the sound of the grunting though – maybe 60 respirations a minute?)

**(I find most parents are fairly confused when I talk about grunting. All newborns squeak, grunt and sigh so parents often can’t tell the difference between the normal sounds and the sounds of respiratory distress. The analogy I use, to help explain the difference, is that a newborn’s airway is like a straw and when the “straw” is kinked, or the airway becomes obstructed, it is a lot harder to get air through. Once the baby’s breathing becomes more labored the baby starts forcing air through their airway, which is why the baby will “whistle” or grunt with every, or almost every, breath.)


Zoe is 6 days old and her last weight was 6 pounds 10 ounces. Mom’s oxygen saturations were 95%. Zoe’s saturations, cuddled on her mom’s chest, averaged 97 – 99% and her heart rate was around 155.

Zoe was placed in the SlingRider per the manufacturer’s directions (pouch flat on a couch, baby secured with the harness and then pouch slipped over mom’s head).

Mom sat down on the couch and I checked Zoe’s position. I noticed Zoe’s upper body and head had rotated slightly away from mom’s body and she had her face near, but not pressing against, the side of the sling. She was not chin to chest.

Zoe had her saturations continuously monitored. For the first 30 minutes her oxygen saturations were stable in the high 90’s (average 95 – 97%). 35 minutes into the test I was noticing a few more brief (3 – 4 second) dips into the high 80’s but with good recovery back into the 90’s. 40 minutes into the test Zoe was experiencing more frequent dips in her saturations but still with good recovery back to normal levels (in the low 90’s). 45 minutes into the test Zoe’s breathing was more labored and it was easy to see the rise and fall of each breath on the side of the sling. Her respiratory rate was 68. Mom (who is a nurse) also counted respirations and counted Zoe’s respiratory rate at 68. Heart rate was in the 150’s. Saturations were averaging 91 – 94% but Zoe’s saturation dips were becoming slightly more frequent and some were in the 82 -84% range. Because of Zoe’s labored breathing, increased respiratory rate and more frequent, and lower, dips in her saturations I decided to pull Zoie out of the SlingRider.

Mom placed Zoe in a wrap and, after about 10 minutes in the carrier, Zoe’s saturations were 97 – 99%, heart rate of 124 and respiratory rate of 52. After an additional 15 minutes in the wrap Zoe’s respirations remained unlabored.


Zoe is now 13 days of age and weighs 7 pounds 11 ounces. When I arrived at Zoe's house she was snuggled in a ring sing in a tummy-to-tummy position. Her head was falling backward slightly in the sling but still well supported by the top rail of the sling. (Zoe's mom said she seems to prefer her head positioned like that and will wiggle herself until her head flops backward slightly.) The middle of the sling was snug so that Zoe's back was straight and not curled. Mom reported that Zoe had been in the sling for 45 minutes before I arrived.

Zoe's respiratory rate was 58, heart rate about 144 and oxygen saturations 94%. Monitoring Zoe for about 5 - 7 minutes and neither I nor Zoe's mother noticed any dips in her saturations below 92%. No grunting noted or labored breathing and Zoe's skin was pink.


Marina is 10 days old and weighs approximately 8 pounds. Mom’s saturations were 94% and Marina’s, in-arms with her mom, were 92 – 97% with a heart rate of 144.

Marina was placed in the SlingRider per manufacturer’s directions. Once the sling was on mom and adjusted we checked on Marina and noticed her head and body were rotated to the side.

Pulling on the side of the pouch Marina was straightened to this position.

Marina’s oxygen saturations were 96%, heart rate of 144 and respiratory rate of 56.

Marina’s saturations stayed in the 90% until 10 minutes into the test. I had gone to the back room to check on my children. During that time I was not actively monitoring the oximeter for a minute or less (I’m guessing less than 30 seconds). Marina’s mother had followed me into the back room. As we were returning to the dining room we both looked at the oximeter and it had a reading of 74%. I opened the top of the SlingRider to check on Marina and her saturations almost immediately returned to normal (97%). I did not note any labored breathing.

20 minutes into the test Marina’s oxygen saturations remained in the mid-90’s and her respiratory rate was 44. She was a little restless.

35 minutes into the test Marina was becoming fussy and pushing on the sides of the pouch. Her saturations were 95% and her heart rate 144. Mother removed Marina from the pouch and fed her.


Miles is 4 weeks and one day old and he weighs approximately 9 pounds. Miles mother has been using an Infantino SlingRider with Miles since soon after his birth.

Mile’s mother arrived at my house with Miles in the SlingRider. Miles was fussy so his mother removed him, fed him and changed his diaper. His mother placed Miles in the SlingRider. I was not aware of it until Miles was removed from the sling but he was placed on top of the swaddle harness. When I questioned mom about this she told me she doesn’t use it because he is so little he doesn’t need it.
Mom’s oxygen saturations were 96%. (Note: I was busy with my children so was not able to get an in-arms oxygen level before Mile’s mother placed him in the sling.)

Here is Miles in the sling. Mom pulled the fabric back in order to make his face visible.

Miles was in the sling approximately 5 minutes prior to me attaching the oxygen monitor to his foot. As I was getting ready to attach the oximeter probe Miles was grunting (wet-sounding nasal wheeze) fairly loudly (I could hear it across the room) with every breath. His respirations were 72 / minute, heart rate averaged 135 and oxygen saturations were averaging 92% with fairly frequent dips into the high 80’s.

Miles remained in the SlingRider for an additional 3 to 5 minutes. He continued to grunt and have rapid respirations. I asked Mom to sit on the couch and place her arm under the sling, around Miles as if she was holding him in her arms. As she did so Miles lifted, his body straightened and the grunting stopped immediately. In less than a minute Mile’s respiratory rate became (a more normal rate of) 44, heart rate 126 and oxygen saturations in the low 90’s (still with a few brief dips in saturations).

Questioning Miles’ mother about her use of the SlingRider.
She stated that Miles was generally noisy in the SlingRider, but more so in her New Native pouch. A friend told her that the noises “were normal”. She stated that, “the noises is how I know he’s asleep and I think, good he’s asleep.”
“The only way he tolerates the sling is if I am moving, walking, exercising.”

A few notes.
We placed Miles both in a ring sling and then a pouch in a tummy-to-tummy position. Mile’s respirations were approximately 52 and he did not grunt. He was very calm, slept the majority of the time and respirations remained unlabored. Heart rate averaged in the 140’s and oxygen saturations 91 – 95% (spot checks and not continuous monitoring).

This is speculation. I was only able to observe Miles for an hour and a half however I noticed in the SlingRider Miles was fussy and/or squirmed and acted restless – even when sleeping. His mother had to vigorously sway, pat him or walk to keep him content. In the ring sling, pouch or in-arms he was very calm, appeared relaxed and did not squirm. Mother did not need to bounce or sway to keep him content. His contentment in-arms and in the ring sling and/or pouch could have been related to his full tummy and clean diaper however, from the comments his mother made, I do not think that was entirely the case. I believe he was fussy in the SlingRider because he was working hard to breathe. I have seen other babies become restless in a chin to chest position but relax once their airway was straightened and breathing became easier.


November 8, 2009

The information on this blog has been up now for almost 18 months and during this time I’ve heard, via comments on, a few questions concerning the information presented here. So to clarify a few points:

1) I know the above bag sling information is on BlogSpot however this was never intended to be a blog. (Does that get me in trouble with the blog police?) I wanted to get this information out on the web, but being webpage creation illiterate, this is the best option I could come up with.

2) That said I’ve heard at least one comment concerning “lack of updates” and “the information being outdated.” First, I stopped doing testing because the sling tests were scaring me too badly and I figured the manufactures should take over testing (which they haven’t). Second, I want to emphasize that the design of most bag slings has changed little, or not at all, since this information was originally published and, as such, the information is still relevant. I think the relevancy is borne out by this October 2009 Consumer Reports blog article concerning the deaths of two infants. Baby deaths raise concerns about Infantino sling

3) The other comment I’ve heard is, “I used one of those slings and my baby was fine.” I’m not saying every single baby carried in a bag sling does poorly however I want to argue “was fine.” I need to emphasize that just because a baby doesn’t suffocate while carried in a bag sling does mean other risks do not exist.

The second greatest risk of bag sling use (after suffocation) is hypoxia. An infant in a chin to chest position, or with nose pressed against the sling fabric or in an enclosed sling without large mesh panels may not be able to get adequate amounts of oxygen. Hypoxia can be very damaging.

The Effect of Chronic or Intermittent Hypoxia on Cognition in Childhood: A Review of the Evidence
“Adverse impacts of chronic or intermittent hypoxia on development, behavior, and academic achievement have been reported in many well-designed and controlled studies in children … as well as in a variety of experimental studies in adults.
Because adverse effects have been noted at even mild levels of oxygen desaturation, future research should include precisely defined data on exposure to all levels of desaturation.”

The third risk is a baby that, because of poor positioning, develops labored and rapid breathing in an attempt to keep oxygen levels at, or close to, normal. A baby fighting to breathe is diverting energy that should be used for growing and developing to the basic task of oxygenation. Not a life threatening risk but obviously not optimal.

In conclusion, there is absolutely no reason to use this type of sling when there are other safe, comfortable baby slings* on the market. None whatsoever. Bag slings are horribly risky carriers. Please, please, please do not take the risk. All it would take is 5 distracted minutes where the sling was not opened so baby could be checked and …

M’Liss Stelzer

• *For safer baby carrier options visit these online stores (and no, I don’t have any financial interest in promoting any of these retailers):


I taught a babywearing class on Saturday (January 23, 2010) and a couple came in with a new design SlingRider. End result is they gave me the SlingRider and bought a Kozy brand mei tai to use instead. I took the SlingRider home and tried it out with my 6-pound demo doll. Now I no longer have my old SlingRider as a comparison because I sent it away to someone interested in the design flaws, however I’m 99% sure the new SlingRider is more shallow than the older version

Placing the my doll in the SlingRider (per instructions) she started up a bit higher but in a few seconds sagged and settled deeper in the carrier however not as deeply as the original. As you can see, the sling appears more open at the top than the original SlingRider.

I tried tightening the shoulder strap all the way (had to take the carrier off and wrestle with the buckle) so that the sling was close to an in-arms hold. Only wearing higher hurt my back even more and, as I walked around the doll started to roll toward me. I pulled the shoulder strap down more across my chest but the doll wrapped around my body so she was almost side lying.

Next I loosened the shoulder strap and found that having the carrier lower was more comfortable for my back. However, carrying lower caused the carrier to swing away from my body if I leaned over.

Transferring my attention to the doll I noticed that decreasing the depth of the sling didn’t make it any easier to see her. Looking straight down.

Making the sling less deep did keep my doll higher (as compared to the depth of the original SlingRider) however, now the doll ended up right under the elastic edge. I don’t know how easy it is to see in the photo but the mesh panel is now draped directly over the baby’s face (FYI my doll has her head permanently turned to her right) and the elastic is on top of her.

Which explains these reviews on Amazon:

“She once turned blue from lack of oxygen after turning her head- the sling was so tight around her head from the elastic that she couldn't get her face out of the fabric. Luckily, I realized she wasn't ok and got her out of it, but it scared the crap out of me.”

"I also found it difficult to place her in because the strap would always cover her face or eyes."

Second problem with the more shallow design is that the carrier appears to shift and roll more than the original. Walking around during one of my trial runs I could feel the side of the sling against my stomach slowly inching downward. It was quite disconcerting. The more I walked, and the further the sling crept, the more tucked into the front of the sling the doll became.

Seems the increased instability would increase the possibility of an infant rolling within the carrier, either toward the front of the SlingRider or toward the wearer.

Amazon review:

“returned Infantino Sling Rider Baby Carrier because it was not safe for my son. Any way I adjusted the sling or my son in the sling, he still rolled towards the front with his face pressed against the mesh of the sling.”

Babies R Us :

"My son was very squished in it and it was difficult to position him in this carrier. His body kept turning towards me so that his face would become covered."

Third, it seems the design tweaks would now force a taller infant’s head up into the pocket created at the shoulder / carrier body attachment point – with very little room for the head and with fabric draped directly over the baby’s face. I know the fabric in the pocket is mesh but it would be impossible to see the baby’s face, then the sling rolls so ... well, I don’t like that.

However, this last point is currently speculation. I would need a longer baby to test this but just looking at the sling it seems that a bigger baby would have his head pocketed.


I had the chance to put a couple babies inside my new style SlingRider (March 2010) and I’m now completely certain Infantino made the new version shallower. However, changing the depth does not appear to have solved any problems, only created new ones.

Here is a 7-week old boy in the SlingRider. I forgot to ask his weight but I’m guessing around 10 pounds.

Before placing him in the SlingRider his mama tried a mei tai, pouch and ring sling and the infant was very happy in all three, and even took a nap, however as soon as mom slung the SlingRider around her body, the baby started crying as if we were hurting him.

Note that the infant’s head is curved fairly high up into the pouch. If he wouldn’t have been screaming and moving, I suspecting his head would have been lolling forward and he would have been chin to chest.

Standing to the side of the sling I could see the baby however, what perhaps is not apparent from the photos, is that baby’s head was deep inside the ‘pocket’ at the pouch / strap attachment point.

I had the mother take a photo with the camera in front of her face. This is what the mom saw when she looked down at her baby. (That's part of the baby's jeans, the harness and one hand.)

This newborn girl is 6 pounds, 3 ounces. As soon as the mother slung her infant onto her body the baby started making loud gasping noises and started fussing. Mother placed her arms under the infant in order to support her and the noises stopped. For the photos the mother gently lowered the sling down and I tried to take the photos as quickly as possible. Neither one of us noted any noisy breathing, or gasping, while the photos were being taken.

She is more visible than the older infant but her face is still partially hidden by the pouch fabric.

A shallower pouch obviously equals less room for the infant. In the original SlingRider a baby this size would not have been curved however, in the new version even this tiny infant was curving up the ‘C’ of the pouch and her chin was being pushed downward toward her chest.

Conclusion: I can understand that Infantino was trying to raise the babies up from the depths of the original version however, making the SlingRider shallower has created new problems:

1) The sling appears to shift more and feels unstable, which may increase the risk of the infant rolling toward the parent.

2) It now pushes even a small newborn chin to chest.

3) Even young infants are pushed into the ‘pocket’ at the strap / pouch attachment point.