Lacto Basics – Breastfeeding in the Emergency Department

Estimated reading time: 10 minutes

Ed – This post will help you understand the basics of breastfeeding, along with how to support patients, relatives and colleagues. 99% of us will learn something new in this post.

Natalie May: I have to be honest; I never used to really think about lactation and breastfeeding much in the Emergency Department, with the notable exception of those times I would be seeing a newborn baby. It’s probably accurate, on reflection, to say that I didn’t think or ask about it in any consultations with patients who were over 6m of age.

Then I had a child – and I thought about breastfeeding ALL THE TIME.

And not just because that was what I was doing every 3 hours or so for 7 months of my life (my child was almost 7m old before he started solids), or because I was back at work and contemplating a time I could escape to express milk for my comfort as much as for my child’s nutrition – but also because there is a lot of “wisdom” about breastfeeding out there, much of which is actually misinformation. I realised I had a huge knowledge gap, but one that wasn’t too hard to fill – and which has already positively impacted my patients (including those significantly older than 6m of age!). So here’s a handy guide to all the things I wish I’d known about breastfeeding before I did it myself.

Three quick points before I get started:

  1. I’ve tried my best to use inclusive language here: I’m using breastfeeding to mean breastfeeding or chestfeeding. I’m not using other gender-specific nouns or pronouns because not all who feed babies from their bodies are women.
  2. I don’t want to get drawn into the politics of feeding babies, because this is an absolute minefield. The best stance we can take in the context of feeding babies is to recognise that there are different ways that babies can be fed and we should support parents and carers to feed their child in the way they want to. Breastfeeding is hard, but so is formula feeding – and parenting/caring for children, for that matter.
  3. Understand that breastfeeding is an undertaking of significant magnitude, and therefore reluctance to make treatment decisions which may have an adverse effect on milk supply comes from a place of having probably battled really hard, through substantial discomfort, over several months to establish feeding – so don’t be dismissive, unempathetic or paternalistic – be collaborative and supportive – it is a big deal.
  4. Huge shoutout to Dr. Laura Howard, Dr. Anisa Jafar and Dr. Lauren Westafer, who have helped review this content.

How Does Breastfeeding Work?

When you’re thinking about breastfeeding in the context of those newborn babies, it’s simplest to consider breastfeeding as a negative feedback loop. The more the breast is stimulated, the more milk is produced. Generally, the more often the baby is put to the breast and/or the more often the breast is emptied, the more milk that should be produced. Other factors affecting production of milk include medications (more on this later), warmth (having the baby skin-to-skin stimulates supply), the nutritional and hydration state of the person producing milk (there is a calorie demand that needs to be met; starvation/excessive weight loss will reduce the milk produced).

Does Supply Vary?

Yes. Milk is produced in very small amounts in the first few days, though we rarely see this in ED because it is under the care of midwives and health visitors. Milk usually “comes in” around day 2 or 3. Supply of breastmilk is usually established over the first 12-ish weeks after delivery/commencement of regular feeding, although it can be regulated or stimulated beyond this point. Some people produce more milk than the child needs. Some produce less. Some produce “exactly”. Supply is usually well established and resilient to time away from child/illness etc by 12 months.

Pumping/expressing milk will also stimulate supply, though direct feeding generally has a greater stimulation effect.

Overstimulation of the breast leading to oversupply is associated with mastitis (more on this later).

Do You Have to Have Given Birth to Lactate?

No. There are ways to stimulate supply in non-birthing parents. This is easiest if the person has lactated previously and works best in combination with lactagogues (medications promoting lactation).

People may choose to stimulate supply for a variety of reasons; adoptive parents of newborn babies, same-sex parents sharing a workload, or other reasons. It would be a mistake to assume that non-birth parents/carers cannot be lactating.

When Do People Stop Lactating?

This is highly variable. Generally, solids are introduced some time around 4-6 months of age. Solid intake is very variable and usually supplementary to a main diet of milk until 12 months of age. Beyond this, cows’ milk can be substituted for breastmilk or formula (or not! If the child has a healthy, balanced diet with other sources of calcium), although many continue to breastfeed beyond this age into toddlerhood. It is a highly individual choice and often hidden from general view because beyond a year of age feeds do tend to be less frequent and associated more with comfort than nutrition, so they are more likely to take place around nap and bedtimes and thus out of public view.

If “full supply” (that is, exclusive breastfeeding) was established, it can take many months for production of milk to stop altogether. Many people find that they can still express a small amount by hand months after they have stopped pumping or direct feeding.

It would be a mistake to assume someone is not breastfeeding because their child is 4 or 5 years old.

When Should I Tell People To Stop Breastfeeding?

Generally, never. It’s really none of your business.

Weirdly, people seem to get this wrong a lot.

But What About Alcohol/Medications/IV Contrast/Mastitis…?

If the person wants to continue breastfeeding, there are very few circumstances in which they will need to stop or “pump and dump” (that is, empty the breast and discard the milk rather than offering it to the child).


For alcohol; unlike in pregnancy where there is a direct blood/baby barrier for alcohol to diffuse across, the alcohol concentration in breastmilk will not equate to a similar blood alcohol concentration in the baby. It’s significantly lower – and then the gut absorption of alcohol from breastmilk is lesser again, such that even if the milk has the same concentration as the breastfeeding person’s blood alcohol level it’s a fraction of the alcohol consumed. The baby’s gut doesn’t magically concentrate the alcohol from the milk into its bloodstream – its the opposite.

The general advice is that occasional alcohol consumption is unlikely to cause harm to a child via breast-milk, however studies into this are few and far between.  If you choose to consume alcohol and wish to reduce as far as possible the concentration of alcohol in your breast-milk then there are ways to achieve this without necessarily needing to resort to “pump and dump” such as expressing or feeding just before having an alcohol-containing drink (and then using the expressed milk to replace the next feed if you have expressed rather than direct fed).

There are other reasons not to be totally inebriated around your child, many around safe sleeping; many continue to avoid alcohol while breastfeeding.


For medications, you can search the Infant Risk Center database. There’s an app, which is not free but is a good investment. For medications, it provides advice as to the risk at various ages and during pregnancy. The vast majority of medications are safe. Please do NOT advise people to stop breastfeeding or to “pump and dump” without checking.

Some medications might adversely affect supply, so this is also worth knowing. Cabergoline is typically used for the specific purpose of inhibiting lactation (for example, in people who do not want to lactate). Bromocriptine can be used for this too.

Antihistamines such as cetirizine and diphenhydramine can inhibit lactation as a side effect – these are meds we are more likely to give inadvertently. Decongestants containing pseudoephedrine will also inhibit lactation, in addition to fertility medications like clomiphene and oestrogen-containing contraceptive medications.

IV Contrast

Generally thought to be safe. Don’t tell people to stop breastfeeding or to “pump and dump”.


Mastitis is a slightly trickier situation because excessive emptying will stimulate more milk production and may worsen mastitis, however draining the breast is helpful. If the person wants to stop lactating, then expressing or emptying for comfort to prevent breast engorgement can be helpful in avoiding mastitis, but there’s a nuanced balance to be struck and mastitis can occur even when feeding is going well.

The milk is safe even in mastitis so feeding or pumping and feeding can continue. Don’t tell people to “pump and dump”.

We might write separately on mastitis management in the future.

Bloodstained Milk From Nipple Trauma

Still ok to feed this milk. If the person wants to continue lactating, don’t tell them to stop. They may need help with latching or with the pain associated with nipple trauma – direct them to a lactation consultant (ideally one qualified as an International Board Certified Lactation Consultant). Don’t tell people to “pump and dump”.


Usually not a problem – when you can safely hold your baby, you can breastfeed your baby. There’s a whole website dedicated to supporting parents with lactation around sedation and anaesthesia here (and FOAMed instagram account here).

How Can I Look After Patients Who Are Breastfeeding?

Firstly, you can recognise that you might not think about breastfeeding in a large proportion of patients, for reasons given above. However, if a patient is breastfeeding and wants to continue, it might be helpful to know so that you can support them through their time in ED and admission, if one is needed.

Secondly, you can check whether medications are safe before withholding them or telling the patient to stop breastfeeding/pump and dump.

In order to maintain supply, breast emptying needs to continue at around the same regularity – at least for the first year or so. That means around every 2-3 hours for the first 6 months in an exclusively breastfed child relationship, and probably a bit less frequently after that although it’s quite variable. Emptying can occur through direct feeding or through pumping/expressing milk. You can advocate for your patient by:

  1. Knowing that they are breastfeeding (this might be a question you want to start asking – just like you ask “is there any chance you could be pregnant?”)
  2. Recognising that if they want to continue, they might need to empty while in ED or in hospital and supporting them to do so, either by allowing the child in to feed directly or by providing opportunities to pump/express along with options to store the milk or send it home with the child.

What Are Galactogogues?

Galactogogues are substances that promote lactation and are used to initiate, support or maintain lactation – some are medications, such as domperidone (or metoclopramide, less frequently). Some are foodstuffs although these are less evidence-based. Fenugreek is probably the most common example of a food used to increase supply. It’s unlikely you’ll be asked to prescribe or assess the need for galactagogues in ED; however, it might be useful to know that sometimes people might take these medications for this reason, and at relatively high doses with possible side effects. You can read more here. (Ed – the Galactogogues really does sound like a Dr Who character from the ’60s).

Can You Get Pregnant While Breastfeeding?

Assuming you are able to get pregnant, then yes. Breastfeeding does reduce the chances of getting pregnant, known as “lactational amenorrhoea method (LAM)“, and is 98% effective – but only in specific circumstances (exclusive breastfeeding, normal menstrual bleeding not yet re-established, within 6m of birth).

And Can You Breastfeed While Pregnant?

Yes, and many people do although it can be more uncomfortable due to pregnancy-associated nipple sensitivity. Some will continue to breastfeed the older child alongside the newborn, a practice known as “tandem feeding“. This study suggests that breastfeeding during pregnancy does not increase the chance of untoward maternal nor newborn outcomes.

Final Thoughts.

Breastfeeding is one of those issues that lots of people have opinions on, and that’s fine. It’s also something that really matters to those who choose, or don’t choose to do it. As emergency clinicians we need to understand the facts and work to support the choices people make, and to help them through any associated challenges. Please share this post with colleagues who might not understand as much as you.

Natalie May @_nmay

  1. Safety of Contrast Material Use During Pregnancy and Lactation.
  2. The Lactational Amenorrhea Method (LAM) for postpartum contraception.
  3. A comparative study of breastfeeding during pregnancy: impact on maternal and newborn outcomes.
  4. ABM Clinical Protocol #9: Use of Galactogogues in Initiating or Augmenting Maternal Milk Production, Second Revision 2018.
  5. Anaesthesia and Sedation for Breastfeeding Parents.
  6. International Board of Lactation Consultant.
  7. infant Risk Centre.
  8. Breastfeeding without giving birth.

Cite this article as: Natalie May, "Lacto Basics – Breastfeeding in the Emergency Department," in St.Emlyn's, April 28, 2022,

1 thought on “Lacto Basics – Breastfeeding in the Emergency Department”

  1. As a new to breast feeding EM doc, I would also add that the thought of being unable to feed your baby through separation or clinical reasons may well cause huge anxiety. Be kind and listen. Where at all possible, flex to facilitate direct feeding (baby to breast) even if it is not typical to have very small people in your dept/clinical area. Phone a friendly specialist colleague in postnatal care/infant feeding (locality dependent) for help if direct feeding isn’t possible.

Thanks so much for following. Viva la #FOAMed

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