More About Milk Let-Down, from Stimuli and Quick Facts

Now that we’ve acknowledged the amazingly complex milk ejection reflex, which you’ve probably heard called milk let-down, let’s explore how certain stimuli may impact let-down, as well as some quick and often unknown facts involving let-down.

1. Do some stimuli increase the likelihood of a let-down?

Yes. Basically, sensory stimuli can improve the mother’s ability to have a let-down. This might include:

• Touch/warmth: Warmth almost always brings on a let-down. It could be the warmth of a baby’s mouth, but a warm compress, placed on the breasts for a minute or so, can help immensely. I’ve also seen mothers stand in the shower and some milk spontaneously flows out.
• Auditory: Hearing a baby cry is a trigger for let-down. Soft, relaxing music, and hypnosis can help, too. Hearing the pump as it’s turned on can trigger a let-down reflex.
• Visual: Seeing a picture of the baby, or even a picture of the baby’s older sibling.
• Olfactory: Nuzzling a blanket that the baby has used.

2. Do some sensory stimuli decrease the likelihood of a let-down?

Yes. Again, these are often sensory:

• Touch/cold: Even a cold draft can sometimes inhibit a let-down
• Auditory: Noise! Sometimes, even seemingly unoffensive noise inhibits a let-down for some mothers.
• Visual: Seeing a very sick infant, or seeing multiple tubes, wires and more attached to a baby.
• Olfactory: I can’t say I’ve noticed this, but I’d wager that it’s a possible inhibitor!

3. Does pain inhibit let-down?

Yes. This isn’t news, but the healthcare team often doesn’t recognize the impact of maternal pain. The relationship between pain and inhibition of let-down was first proven in the 1950s by a research study conducted by Dr. Niles Newton.

I encourage mothers to take pain medication, especially in those first few days after having cesarean surgery.

4. Can drugs inhibit let-down?

Yes. Oddly, I cannot find a solid evidence-based list of therapeutic drugs that affect the milk ejection reflex.

However, large amounts of alcohol – which is a drug – can most certainly affect the milk ejection reflex. Coiro et al and Cobo showed years ago that having two or more drinks inhibits the MER.

What’s more, as explained in the LactMed database, breastfeeding after 1 or 2 drinks can reduce the infant’s intake of milk, which could then perhaps reduce supply.

I’ve had much more to say about alcohol. (Here we are again – we’re talking about that magic triangle!)

5. Does oxytocin spray promote let-down?

Well, in the old days, we thought so. And it just makes sense, right? If natural oxytocin is circulating in the body, synthetic oxytocin that is “sniffed” should have the same effect, right?

It doesn’t.

Research has shown that while sniffing the oxytocin spray helped with let-down, it didn’t help any more than sniffing a saline solution. Hence, the oxytocin spray was no more effective than the placebo.

6. Does general “stress” decrease the likelihood of a good let-down?

Unquestionably, yes. It might be:

• criticism from a friend, relative or unsupportive healthcare personnel
• rushing to be on time for a doctor’s appointment
• worrying about a sick premature baby

Remember, too, that there are many stressors that healthcare professionals — or even the mother herself — might not recognize.

I distinctly remember one woman who told me she didn’t have any stressors. A little later, I discovered she had had to take the city bus to see me, she had serious visual impairment, and she had a newborn in the NICU hanging between life and death. Uh, right. In my book, she had some stress!

7. Is self-talk related to milk let-down?

In my view, a major deterrent to a good milk let-down is negative self-talk. I’ve been hugely enlightened by the solid research cited in Dr. Ethan Kross’s book, Chatter, which discusses how self-talk can positively or negatively affect our experiences. (Another good book is What to Say When You Talk to Your Self by Shad Helmstetter.)

After many years of clinical practice, I’ve noticed how the stories people tell themselves aren’t just “in their heads.” Those stories affect their bodies, too. The subconscious mind is very powerful.

8. Is lack of confidence related to difficulty letting down?

Lack of confidence has been shown to affect the number of months a mother breastfeeds. But I’ve never seen any studies to substantiate the relationship of confidence to let-down. However, I believe that lack of confidence is grossly underestimated in breastfeeding situations.

Remember this. We can offer encouragement and praise, but it’s difficult, if not impossible, to “give” people confidence. That is, we can’t wave a magic wand or simply “bestow” this capability onto them. However, it’s very easy to lower their confidence.  

9. What else can inhibit let-down?

Being overtired, exhausted, or sick can inhibit the milk ejection reflex. Distractions are another possible explanation. 

10. Can a mother have more than one let-down during a feeding?

Absolutely. Research studies have shown this, and I’ve seen it in clinical practice, many times. It makes total sense to me. A woman can have multiple orgasms within a few minutes. Remember, the same hormone that governs let-down governs orgasm.

11. What happens if a mother has a forceful let-down?

Sometimes, babies will literally pull away from the breast if they find themselves dealing with a forceful let-down. It’s sometimes called an over-active let-down.

There are a bunch of things you can do to help that situation, but one is, be aware that the baby is not “rejecting” the mother or her milk. The gagging and pulling away is a sign that the baby just can’t cope with all that volume at once.

12. Can mothers experience let-down after weaning?

Yes, absolutely! I’ve known of women who report a let-down a year or more after their last baby was weaned.

13. Can mothers experience a let-down when they aren’t with their babies?

Absolutely. For some mothers, just thinking about their baby can trigger a let-down reflex. Hearing a stranger’s baby cry in the supermarket can also elicit a let-down for some lactating mothers.

14. Do some mothers leak more than others?

Yes, definitely. It depends somewhat on that sphincter muscle.

Some mothers never leak much, if at all. Others leak frequently and in copious amounts.

I distinctly remember a mother who worked in an office, and said she leaked all day, every day, even if there were no babies present. She wore five breast pads at one time, and she changed them frequently to avoid having her milk leak through her clothes.

15. What’s the relationship of milk fat to let-down?

Human milk contains the macronutrients of protein, carbohydrate, and lipids (including fat). The fat tends to stick to the lining of the milk ducts. Hence, when let-down occurs, the fattier milk is forced down into the milk ducts.

16. Do mothers have trouble letting down to pump?

Yes, some do. Because it’s a neuroendocrine response – involving both neurons and hormones – emotions affect let-down.

I’ve known many mothers who have pumped, but none have ever told me they “love” their pump. Without the emotional piece, some mothers find it difficult to let down to a pump. Warming the flanges and using those other sensory triggers, can help.

17. Is there such a thing as a dysphoric letdown?

Yes. My podcast guest Alia Macrina Heise described about dysphoric milk ejection reflex (D-MER). You will be very surprised by this.

That’s all I can think of at the moment. In the comments below, tell me what surprised you most, or what other questions you might have!