Some moms with sensitive reflexes can let down their milk either right before or right at the beginning of a breastfeeding session. Many women experience an uncontrolled let-down reflex when they hear a baby cry or think of their child—suddenly, milk will begin to flow even if their baby is not nursing.
Since your brain is wired to care for a newborn, other things may trigger the let down reflex. If your baby cries, or if you hear any baby cry, your milk may let down in response. If you go too long without nursing and your breasts get too full, your let down reflex may trigger to relieve the pressure.
When your baby sucks at the breast, tiny nerves are stimulated. This causes two hormones – prolactin and oxytocin – to be released into your bloodstream. Prolactin helps make the milk, while oxytocin causes the breast to push out the milk. Milk is then released or let down through the nipple.
Your breasts will start to make milk in the first couple of days after you give birth. This happens even if you don't breastfeed. You may have some milk leak from your breasts, and your breasts may feel sore and swollen. This is called engorgement.
Gently hand expressing milk behind the nipple may be more effective than a breast pump when milk won't seem to flow. Alternating a gentle breast massage (below) with hand expressing may help to gently clear the “traffic jam” behind the nipple or release blocked ducts within the breast.
For infants, not being breastfed is associated with an increased incidence of infectious morbidity, including otitis media, gastroenteritis, and pneumonia, as well as elevated risks of childhood obesity, type 1 and type 2 diabetes, leukemia, and sudden infant death syndrome (SIDS).
To put a number on it, it usually takes about 20 to 30 minutes after feeding to generate enough milk for your baby, and about 60 minutes to replenish fully. The more often your baby feeds, and the more they empty your breasts, the more milk your body will produce.
In Summary
If you're not breastfeeding, breast engorgement may likely go away by itself in 7 to 10 days as milk production ceases. In the meantime, you can apply ice packs for the swelling or take pain medication to help with the symptoms.
When you start pumping, most pumps will begin in the “letdown phase” – which is lighter and quieter – for about two minutes.
Some gentle breast massage prior to pumping may help stimulate a let down since it's the nerves in the breast and nipple that send the message to your brain to let down milk. Massaging the breast or applying a compress during pumping may also help.
Baby keeps pulling away while breastfeeding
Babies are still learning to regulate their suck-swallow pattern. Once the let-down starts, some breastfed babies struggle to keep up with the fast flow of milk. If they're overwhelmed, this can make them pull away.
Baby's frustration may just be a sign that she's finished and wants to move on. On a similar note, an occasional baby will just want to suck at the end of a nursing session and the flow of milk with let-down frustrates her.
But they say this crankiness in babies is normal and just their natural way of communicating their needs to their mother and is no cause for alarm. For example, some cries will be down to tiredness not hunger.
Signs of an overactive letdown
Babies may also experience painful and excessive gas, hiccupping or spitting up. This may make you think your milk doesn't agree with your baby, but that's generally not the case. It's more about the fact that he can't handle so much all at once.
Some might feed every 90 minutes, whereas others might go 2–3 hours between feedings. Newborns should not go more than about 4 hours without feeding, even overnight.
The more milk your baby removes from your breasts, the more milk you will make. Despite views to the contrary, breasts are never truly empty. Milk is actually produced nonstop—before, during, and after feedings—so there's no need to wait between feedings for your breasts to refill.
Adequate hydration also is important for breast milk production. The amount of liquid you put into your body affects how much breast milk you can produce. I encourage women to carry a bottle of water for themselves in their diaper bag.
Your breasts will likely become engorged.
Three to four days after delivery, your breasts may grow to a size you previously couldn't have imagined. They may also become almost rock-hard. This is engorgement.
Although estimates suggest that only about five to 10 percent of women are physiologically unable to breastfeed, many more say that they're either not making enough or there's something nutritionally lacking with their milk that keeps the baby from thriving.
Your breasts feel softer
This happens as your milk supply adjusts to your baby's needs. The initial breast fullness reduces in the first few weeks. At around 6 weeks, breast fullness is completely gone and your breasts may feel soft. This is completely normal and has no effect on your milk supply.
If there is a continual delay in letdown from the breast it can lead to reduced milk supply. Babies are also really in tune with how their mother's are feeling. Your baby can totally sense when you are sad, stressed, or anxious.
You're not getting let down. If your breasts feel like they're full but you're not able to get the milk flowing out when you pump, it could be that you're not achieving let down. The let down reflex releases your milk from the milk ducts. This only occurs when you're either breastfeeding or pumping.