Exclusively Breastfeeding Mothers Get More Sleep: Another Look at Nighttime Breastfeeding and Postpartum Depression
In a previous post, I described the results of recent studies that indicated that exclusively breastfeeding mothers appear to get more sleep than their mixed- and exclusively formula-feeding counterparts. That blog post generated quite a bit of comment. For many of us, the findings of these recent studies seemed completely counterintuitive—how could the breastfeeding mothers get more sleep? I have to admit, this research changed my mind. For years, like many breastfeeding researchers, I assumed that breastfeeding mothers got less sleep. But research over the past five years has proven that these assumptions were wrong.
In this post, I’ve summarized the findings from our study (Kendall-Tackett, Cong, & Hale, 2011). These findings were published in the journal Clinical Lactation. Our sample was 6410 mothers of babies 0-12 months old. The mothers ranged in age from 13-50 and they completed an online survey with 253 items that were all about their sleep patterns, infant sleep location, the mothers’ physical and emotional health, their pregnancies and birth experiences, their trauma history, and detailed questions about how they feed their infants. For these analyses, we asked a summary question about feeding method: “Since your baby was born, did you breastfeed, formula feed, or both breast and formula feed?” We then examined several indices of mothers’ sleep and well-being. We found that on all measures, breastfeeding mothers reported significantly better functioning. They were getting more sleep, felt better during the day, and were less depressed. Interestingly, there was no significant difference between the mothers who were either mixed- or formula-feeding on any measure. This suggests a threshold effect for breastfeeding: that mothers who supplemented did not have the same physiological benefits as mothers who only breastfed. The babies, obviously, benefit from receiving their mothers’ milk. But the mothers get more physiological benefits if they can breastfeed exclusively. Below is a summary of our findings.
Breastfeeding mothers reported sleeping significantly more hours. Two previous studies found that mothers’ reported hours of sleep is a better predictor of lowered PPD risk than measures of mothers’ “actual” hours of sleep recorded via polysomnograph.
Figure 1. Number of hours mothers report that they sleep.
Consistent with getting more sleep, breastfeeding mothers reported more daily energy and better overall physical health.
Fig. 2: Mothers’ Daily Energy on a Five-Point Scale
Fig. 3: Mothers’ Overall Rating of Their Physical Health
Consistent with previous studies, breastfeeding mothers also had lower risk for depression as measured on the PHQ-2.
Fig. 4: Maternal depression
I would like to anticipate a couple of questions based on questions I received from the previous post. First, the breastfeeding mothers were not all bedsharing. In fact, they were pretty evenly divided between bedsharing and baby in a crib in another room. [Click here to read this article.] I suspect that these findings would be even stronger if we only included the bedsharing mothers. Second, many readers wondered whether we were trying to prove causation with correlation. We were not. We used analysis of variance to examine mean group differences. Consistent with our findings, we can report that, for example, breastfeeding mothers reported a significantly higher number of hours of nightly sleep.
The findings from our study are quite consistent with previous studies, and they suggest that when mothers start supplementing, that they actually get less sleep. So that strategy that her family, and many professionals, are likely to suggest (i.e., have someone else give the baby a bottle, or have the mother give the baby a bottle herself) could actually make things worse. In the next post, I will give some suggestions about what you can do to help a mother who is overly fatigued.
Reference
Kendall-Tackett, K. A., Cong, Z., & Hale, T. W. (2011). The effect of feeding method on sleep duration, maternal well-being, and postpartum depression. Clinical Lactation, 2(2), 22-26.
Posted by: Kathleen Kendall-Tackett,PhD, IBCLC, FAPA, is a health psychologist and board-certified lactation consultant. She is clinical associate professor of pediatrics at Texas Tech University Health Sciences Center in Amarillo, Texas. She is owner and editor-in-chief of Praeclarus Press, a small press specializing in women’s health. She can be contacted at www.KathleenKendall-Tackett.com.
“Theysuggest that when mothers start supplementing, that they actually get less sleep.” Maybe I’m missing something, but how do we know they didn’t start supplementing due to lack of sleep rather than having less sleep due to supplementing?
I absolutely agree with these findings. I am a mother whom has been exclusively breast feeding her now 6 month old son and can say that it has benefited my health and mind as well as that of my baby’s. He is an active, healthy and energetic baby I can keep up with because of the extended hours of sleep I get nightly. If you are looking to get up in the middle of the night to make a bottle by cleaning or sanitizing one, pouring mixing, adding water to and/or heating one up, then it sounds to me like thats a lot more work to have to do every two hours than to nurse your child naturally the way nature intended and get right back to sleep after satisfying your child’s needs. Don’t knock it till you try it. And if you have tried it, cudos on the attempt, nothing is easy at first but persistence, determination and positivity pay off well in the end. Baby will thank you in the form of contentment and you will feel accomplished and should feel very proud to have escaped the clutches of manufactured powders and liquids. Theres no need to jump off of a bridge with the masses. Women were made to nurse their children.
@Indie
My thoughts exactly! I’d love to believe it’s true, but it seems equally possible that women might turn to mixed- or formula-feeding *because* they are getting less sleep and/or have higher levels of PPMD.
Rosie, I 100% agree with you. I have been exclusively nursing my 4month old son now, and its awsome! It has made me feel better, my son feel better, and it has created a closer bond between us. Nursing at night is a breeze! My little guy can find my nipple in the dark without a problem, I can latch him on and go right back to sleep without a hitch! I do get more sleep than the average formula feeding mom, and I dont have the mess to worry about in the morning when I wake up!
I will say this, while I think for myself I did get more sleep, but I don’t think I would have admitted it at the time. I recall with my daughter, she slept in a crib in her own room, and I loathed getting up to feed her at night. I LOVE sleep. I felt exhausted. Bringing her to our bed, realized that, but honestly, I didn’t sleep well at all with any of my children b/c I hate being touched at night. I miss them in our bed now that they are older, but I get so much more sleep now and feel better. Having never given artificial milk to my babies, I can only compare to the first few weeks our daughter slept in her room to when she slept with us. I did get more slept, but it was no where near to restorative sleep. With our 3rd, I did suffer some malaise after his birth and exclusively breast feed him. So, does this lessen the chance of PPMD??? Maybe, but like with all these studies, we have to be careful and we have to look at EACH mother/baby pair.
@Rosie I breastfed for 7 years straight and never gave a drop of formula to any of my children. But that doesn’t change the fact that this article does not address my question.
We’ve gotten a few questions on this that I think I can address. There is not question in my mind that a mom may try formula because she is tired, and so yes, there can definitely be a bi-directional relationship between fatigue and formula use.
But in terms of this study, you need to ask what happens next after they start supplementing. This study looks at the present. It’s not looking back and saying were you tired before you started? If formula was helping these mothers be less fatigued, wouldn’t we have seen that they were less fatigued when we asked about their current state? But that’s not what we found. Even though they had been supplementing, they were still MORE tired, they still reported LESS sleep and that it took them MORE minutes to fall asleep. So the question I have to ask is if this was helping, when should these effects kick in?
It’s also important to remember that this is still postpartum. Everybody’s tired. But the key question is are mothers more or less tired if they supplement? In other words, does supplementing help mothers be less tired? I think the answer from our study and the previous studies is an unequivalical “no.” I would encourage you to read the full article. There is a link to it on the posting.
So the next question we should address is what should we do to help a tired mom? My next post on Science & Sensibility will specifically address this. So please understand that I would never tell a mom to just tough it out. If a mom is really tired, we need to ask some more questions and see if we can figure out why.
Perhaps moms who breastfeed report less fatigue because breastfeeding is driven by hormones and maybe it promotes deeper sleep in the mom? Since it is a hormonal process and we know hormones affect sleep.
Mothers probably have higher rates of depression when they formula feed because breastfeeding gives off certain hormones that create an instant feeling and bond with your baby. Mothers are probably very dissapointed if they weren’t successful with breastfeeding. They may not feel as much of a bond. They may feel like a failure. Etc.
Perhaps breastfeeding regulates the postpartum hormones as well. (This would explain why formula feeding moms have less physical well-being, less energy, etc.) If a woman has a thyroid postpartum condition or postpartum hormone imbalance, she is going to have a lot less energy, insomnia, etc.
Personally, I know these findings are true. I had my son at the tail end of a full time graduate program then went back to full time work as well at 7 weeks. Breastfeeding (and co-sleeping) saved us so much time and allowed us all more sleep than having to get up and make bottles all night! I am so pleased you are sharing these important studies. Less sleep for breastfeeding mothers is one of the many breastfeeding myths that need to be debunked. Thank you!
Personally, I did not get more sleep when I breastfed. I breastfed for the first few weeks of my sons life and I was overly tired, couldn’t ever get anything done, and my sex drive went way down. Now that I formula feed, I get a lot more sleep. However, this is NOT the reason I switched. My son couldn’t latch well do to his tonuge muscle on the bottle of his tonuge being connected unusual so he couldn’t maneuver it correctly. He is now 3 months old. I wish I could have breastfed a little longer than I did but, I know now that for my son
and I at least, we both sleep better when we can’t hear each other moving or sleeping at night.
The reason breastfeeding made you more tired is the tongue tie your son has. Tongue tied babies do not remove milk from the breast well, they frequently never fill up, they are always eating, they can be very gassy and very fussy, difficult sleepers. Fixing the tongue tie whether anterior or posterior typically resolves the problem. I get so frustrated when moms report these problems and instead of getting help the doc says formula. My 3rd was tongue tied. She is currently 5 months old. She had all of the above symptoms and I had terrible nipple pain. I had her tie clipped at 12 days old and ta-da: problems solved. And I bf all 3 kids and bedshare and we get awesome sleep. 9-11 hrs of sleep I barely notice when the baby latches on. I couldn’t survive parenting any other way.
Of course it is hard to diagnose a specific reason for fatigue in a particular mother without intimately knowing the situation but, yes, as Kendra points out, in general–tongue tie can have very drastic repercussions on not only the breastfeeding process itself (inefficient milk draw) but on situations that poor breastfeeding can affect downstream (like sleep/rest). It is unfortunate that not all practitioners who interact with mother-baby dyads know how to recognize this scenario and offer proper treatment (and proper advice).
Absolutely there would be greater benefit to baby if breastfeeding! The finding of lower postpartum depression is terrific. Your exaggeration of SO many more hours of sleep and the graphs is laughable! The difference is 0.2hr = 12min to supplemented feeding and 0.3hr = 18min for formula fed babies. There are so many more components that must be taken into account for the amount of sleep and be divided in this study such as: other children, nanny’s/help, working mother, age of child.
Interesting study, and I hope to see the studies replicated by other researchers so we can continue to support moms & families with evidence-based information as they make their own choices for their own situation. Thanks for doing the research and helping us with real information to inform our decisions and practices. Tweeted & FB!
@Heather
Hi Heather.
it’s not as trite a difference as it might sound. It was making a huge difference in multiple layers of mothers’ wellbeing–including their depression risk. So although it ay sound like a small difference, the mothers were not experiencing it as such. And that’s what ultimately matters. Kathy
I find this very hard to believe. I can’t remember the last time I got a decent night’s sleep. I have never been so tired!
I have done all three with two children. Special circumstances meant they were both combination or formula fed in the first few weeks of life. My second thereafter I exclusively breastfed for another 9 weeks. Yes it was easier and you sleep more because you don’t need to come fully out of sleep mode. The body is designed to hold baby without effort. If you start dozing with a bottle in your hand it starts to fall away. This is the reason why, you actually have to fully wake to feed. But really it needs to be looked at why mothers mixed or formula feed. That cause is more likely to be the cause of lower wellbeing. Both my daughters were lactose intolerant. Both had terrible colic. And yes I felt a failure both times for not breastfeefing. I really believe the causation of formula feeding wad behind my depression. But we should look at the plus side of formula feeding. The extra bonding fathers get. I know ky husband loved it and felt out of it when I was exclusively breadtfeeding. We’ve got to see the whole picture.
Lisa – thanks for sharing your experience. I just wanted to mention that in our childbirth classes we cover suggestions on how to provide special bonding for dads/partners regardless on how the baby is being fed. Dads/partners have shared at reunions such creative strategies as making a commitment to hold their baby for at least the same length of time their partner breastfed the baby, another partner scheduled at least 3 skin to skin sessions daily with their baby, another shared how he always sat close and read to the baby whenever he was home and the baby was being breastfed and others have shared the more common mantra – mother is in charge of input and partner is in charge of output. I can’t put my fingers on the study but I remember reading that even when a mom switches to formula feeding to get more help feeding the baby, she ends up still doing 95% of the feeding.
Fascinating article. I’ve exclusively breastfed my now 27 month old since birth and although I have no other comparison, I feel I’ve definitely experienced sleep deprivation!! We also “bed share” (to this day) and until about 4 months ago, night-nursed, EVERY night. Even now, I still feel sleep deprived though not nearly like I did before. Regardless, I chose to suffer the sleep deprivation as it’s been more important to me that she receive only my milk. Thanks for sharing this interesting bit of research….
@Indie
Totally agree. I started supplementing because we were getting so little sleep. I got substantially more sleep when I could nurse at 9 and go to bed and my husband could feed a midnight bottle and I didn’t have to get back up until 4 or so to feed. Cross-sectional studies can only describe a situation, not explain it.