Babies were made to breastfeed, but in the real world, most babies get a bottle at some point. Some babies only have the occasional bottle and other babies have several bottles a day because their lactating parent works. Babies get milk differently from the breast vs. a bottle. Understanding the differences and some bottle background information can help you make choices that support your baby’s best feeding development and experience.
Breastfeeding vs. bottle feeding mechanics
- Muscles - breastfeeding uses more muscles and jaw movements than bottle feeding.
- Lips - the lips form a seal at the breast and bottle.
- Tongue - movement of the tongue during bottle feeding is piston-like compared to wave-like during breastfeeding.(1)
- Milk flow- the baby needs to actively remove milk during breastfeeding. Bottle feeding is more passive. Milk flow is more constant with bottles compared to the breast which has periods of fast flow during a milk ejection and periods of slower flow.
- Milk removal - bottle feeding is achieved from suction and compression. Breastfeeding is achieved by the baby creating positive pressure, pressing the breast tissue to the roof of the mouth to compress the milk sinuses, and then creating negative pressure for milk to be removed out of the nipple.
- Control - the baby controls the process of breastfeeding but the parent is more in control during bottle feeding. Be cautious of overfeeding with bottles.
Bottle flow rate
When a baby breastfeeds, they latch deeply and use suction to draw the nipple in and back towards where the hard and soft palate meet. Using their tongue, they begin nursing, getting a couple of drops of milk. The beginning of sucking releases the hormone oxytocin in the parent which sends a message to release milk and she experiences the milk ejection reflex or milk let-down. The baby’s suck pattern changes as they get a larger bolus of milk from each suck. They will need to swallow more during this time. As milk flow slows down again, they suck a few times to create a bolus of milk before swallowing, also giving them more time to breathe while they continue nursing.
When the baby is drinking from a bottle, we want them to have time to breathe, time to have controlled swallowing, and not be overwhelmed. During swallowing, a baby closes their airway for just that moment. The slower the bottle feeding, the more opportunity the baby has to breathe and maintain their oxygen levels while they take the bottle. How we position the baby during feeding makes a big difference. If they are in our classic magazine cradled hold with the milk continuously flowing into their mouth, they must swallow which means fewer opportunities for breathing.
Don’t believe the marketing! Just because a bottle is marketed as slow flow, that doesn’t mean it actually is. Even among the same bottle nipples, not each one has the same flow rate.(2) In a study of 45 different nipple brands, testing 10 of each, showed there is a range of flow rate from 2 mL/minute to more than 80 mL/minute.(2) Another study of 26 different brands showed similar results with a range of 1.68 mL/min to 85.34 mL/min.(3)
Babies who have great oral function and are healthy full-term babies may not have a problem handling the fast flow from the bottle, but babies who have feeding challenges or are born prematurely may have a hard time with a bottle that has a faster flow. Remember, the flow from a bottle is also continuous and should be taken into consideration when we consider how to feed a bottle.
- The baby is sitting upright on the caregiver's lap, but the baby still has to be supported by the parent or caregiver
- A slower way to bottle feed
- Still controlled by the parent or caregiver
- Milk may still pool in baby’s mouth
- Encourages the caregiver to follow the baby’s cues
- Bottle is held horizontal to the floor and tipped down or up to pause or deliver milk to the baby
- Can still be tiring for the person feeding the bottle
- Side-lying paced bottle feeding gives the baby more control over the feeding
- A slower way to feed the baby
- Reduces the pooling of milk in the baby’s mouth. Instead, excess milk will drip out the side of their mouth
- More baby controlled
- More closely mimics breastfeeding position
- Baby can pause as they desire during the feeding
- Baby’s body is fully supported and has greater postural stability
- Allows the baby to actively feed rather than passively feed
- The bottle is held horizontal to the floor and can be tipped up to make milk available to the baby or down to stop milk flow when the baby pauses their suck pattern
- Supports breathing and swallowing coordination
- Supports digestion
- Very comfortable for the person feeding the bottle
Going back and forth between breast & bottle
- Paced bottle feeding and feeding a bottle so the baby uses their reflexes for feeding support the baby being able to go back and forth more easily between the breast and bottle.
- We still want them to open their mouth wide and take a large portion of the nipple in their mouth whether at breast or bottle.
- Placing the bottle on their chin first, signals to open wide.
- Put the bottle nipple in their mouth so their lips can flange close to the base of the nipple.
- Bottle nipple style matters! Choose a bottle nipple with a gradual slope from nipple tip to base.