The let down reflex is what allows your breast milk to flow.
Your baby's suckling stimulates tiny nerves in your breast tissue. This causes both prolactin and oxytocin to release into your bloodstream.
Prolactin drives breast milk production. Oxytocin causes your breasts to ‘let down’ and release milk. It causes the milk ducts to widen and the alveoli to contract, which drives milk down the ducts toward the nipple.
The let down reflex is sometimes called the Milk Ejection Reflex (MER).
In this article:
How is let down stimulated?
Let down can be triggered by both physical and emotional stimuli.
Physical touch and suckling, by your baby, breast pump or even partner can cause your milk to let down.
Emotional stimuli like hearing your baby cry, seeing your baby or even thinking about or smelling you baby can trigger let down.
The let down reflex usually occurs multiple times in each feed. Most women only feel the first let down of each feed. Over time the let down reflex often becomes less noticeable.
What does let down feel like?
Women feel a wide variety of sensations during let down. Or sometimes, nothing at all.
Some of the signs of let down include:
Common problems with let down
Let down feels different for everyone, and there is no normal.
If you're comfortable while breastfeeding or pumping, and your baby is growing, there's no need to think about let down.
If you have a slow, unwanted, painful or forceful let down - read on.
1. Slow let down
Some women don't feel let down at all. If your baby is growing, you don't need to worry about how slowly your milk releases, or how it feels.
For some women, a slow let down might cause you baby to cry or get distracted, or simply make their pumping session take too long.
Try these let down tips:
Control what you can, and let go of the rest.
Take it one feed at a time, and know that most women find their flow over time.
2. Leaking and unwanted let down
Some women find their let down reflex activating very easily. This can cause leaking, or even spraying milk from the breast unexpectedly.
The trigger might be a baby crying (yours or otherwise), sex, a warm shower or relaxation practices like meditation or even sleep.
Leaking is very common in the early stages of breastfeeding, as your body and baby find their supply/demand fit. Wearing breast pads can help to protect your clothes.
If you continue to have unwanted let down and significant leaking beyond 6 months, talk to your doctor, midwife or lactation consultant about your options.
3. Painful let down
Minor pain during let down, especially early on, is very common. This can result from overfull breasts or conditions like damaged nipples, mastitis and thrush that should be treated separately.
- Damaged nipples
Uterine contraction (abdominal cramping) will improve over time, and is a healthy sign that your uterus and reproductive organs are returning to their normal size and position after birth.
If your breast feel overfull, you can pump or hand express a small amount to relieve the pressure before you feed.
Painkillers like paracetamol and Ibuprofen can also be used to relieve painful feeding from nipple damage.
If you believe you have mastitis or thrush you should visit your doctor, midwife or lactation consultant for treatment.
4. Fast or forceful let down
If your baby is gagging, choking or coughing as your milk lets down, you may have a hyperactive let down.
It's likely your baby will 'grow into' your strong let down, and your supply will regulate over time to help slow the intensity.
If your baby is getting too much milk too fast, it can sometimes result in swallowing air - which can lead to increased gas and fussiness.
Your milk might also be spraying or leaking heavily.
Tips to slow the flow:
Negative feelings on milk let down
A small portion of women experience Dysphoric Milk Ejection Reflex (D-MER) on let down. D-MER is an abrupt feeling of dysphoria (or negative emotions) just before milk release. It is thought to be caused by a sudden decrease in dopamine in the brain.
Dysphoria is the opposite of euphoria, and characterised by unpleasant mood, sadness, depressed mood, anxiety, irritability or restlessness. It lasts no more than a few minutes after let down occurs.
D-MER is controlled by hormones, not the mother, and is entirely distinct from postnatal depression. It is entirely physiological and a direct response to milk ejection.
If you think you might be suffering from D-MER discuss it with your doctor, midwife or lactation consultant, or explore the information available at D-MER.org
A final word
Remember, there is no normal. Let down feels different for everyone, and it's common to get off to a leaky, messy start. If you look close enough, there is beauty in the chaos.
Seek support, rest when you can, and above all be kind to yourself.