The Fourth Trimester

Have you ever heard of the 4th trimester? This is based on the thought that babies are born 3 months early due to the increase in head/brain size as humans developed. This means that babies are born too immature and require 3 extra months of womb-like settings to help their development. This concept has been popularized by Dr. Harvey Karp, MD in his book “The Happiest Baby on the Block.”
 
There is evidence that around 3 months of age, there is a bio-behavioural shift that occurs in infants. This includes more awake time during the day, longer periods of sleep at night, and more socially-oriented behaviour such as eye contact, smiling and cooing.  Infants are more able to regulate themselves and become less dependent on their caregivers.  So why do we simulate a womb-like environment for the 4th trimester? To get them to this bio-behavioural shift with minimized sleep impairment, parental exhaustion, and depression!

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In his book, Dr. Harvey Karp discusses how the rhythms inside the womb trigger a calming response. This response allows infants to switch off crying and switch on sleep. These rhythms consist of the 5 S’s to help soothe babies during the fourth trimester. These 5 S’s have been shown to significantly decrease excessive crying in infants under 4 months of age.
 
1. Swaddle- this recreates the tight-packed position inside the womb and decreases the startle reflex which allows for increased sleep. How to swaddle correctly: wrap arms snug, straight at their side. Note swaddling must stop when baby can roll. The DUDU method- down, up, down up. See link in bio for more information on swaddling!

2. Side-Stomach
Holding baby in these positions will allow for the calming reflex to be activated. Back sleeping is the recommended safe position for sleeping, but to calm your baby try holding them in these positions or over your shoulder.

3. Shush
In the womb, baby can hear all the sounds that come along with blood flow, digestion, etc. This means they are soothed with shushing noises and other white noise vs total silence.

4. Swing
In the womb the baby is suspended in amniotic fluid and is jiggling around as you walk and move. This is why rocking is so calming to them outside the womb. If the infant is calm, slow rocking will be fine, but if they are upset, they will need fast, tiny motions to initiate the calming reflex. Make sure the movements are small (less than 1inch back and forth) and you are supporting their head and neck while you move.

5. Suck
This is described as icing on the cake of calming. This sucking action will help soothe them into relaxation. In-utero infants often swallow amniotic fluid in a sucking motion which helps soothe them and prepare for breastfeeding. 
 
These skills work best when done correctly. Make sure to practice swaddling when your little one is calm (it is much easier than with a screaming infant).


​How can a chiropractor help with this? Short answer- they don't. Chiropractic care is focused on the healthy alignment of the spine and the impact it has on your baby’s nervous system and its ability to function effectively. Why would infants develop dysfunction in the spine? Birth, no matter how baby was born, can be traumatic for babies and create misalignments in their spine which is what chiropractors check for and correct with gently adjustments. How well your baby’s spine and nervous system functions can help establish overall health in your child, not to mention parents’ well-being and connection with their newborn. Chiropractors can also offer advice on how to help get gas and burbs out, tricks on feeding, and how to help comfort a child in the first 3 months postpartum. If you have any questions, please feel free to reach out! To learn more about the 5 S's and Dr. Harvey Karp click here!

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 Disclaimer: The advice provided in this article is for information purposes only. It is meant to augment and not replace consultation with a licensed healthcare provider. Consultation with a Chiropractor or other primary care provider is recommended for anyone suffering from a health problem.  

References
1. Möller EL, Oort FJ, Rodenburg R. Effects of a Responsive Soothing Intervention on Infant Excessive Crying and Infant Sleep. Manuscript under review. 2018.
2. Infant development and developmental risk: a review of the past 10 years. Zeanah CH, Boris NW, Larrieu JA
J Am Acad Child Adolesc Psychiatry. 1997 Feb; 36(2):165-78.
3. Whose clock makes yours tick? How maternal cardiorespiratory physiology influences newborns' heart rate variability. Van Puyvelde M, Loots G, Meys J, Neyt X, Mairesse O, Simcock D, Pattyn N Biol Psychol. 2015 May; 108():132-41.
 4. Behavioral and physiological responsivity, sleep, and patterns of daily cortisol production in infants with and without colic. White BP, Gunnar MR, Larson MC, Donzella B, Barr RG Child Dev. 2000 Jul-Aug; 71(4):862-77.
 5. Crying babies, tired mothers: what do we know? A systematic review. Kurth E, Kennedy HP, Spichiger E, Hösli I, Stutz EZ
Midwifery. 2011 Apr; 27(2):187-94.