Alcohol in Pregnancy and Breastfeeding
By: Sabina Vm
Tags: Breastfeeding, Alcohol, Pregnancy

Alcohol in pregnancy

There is no safe level of consuming alcohol in pregnancy. Alcohol crosses the placenta easily. It is difficult to predict what the threshold of alcohol is, and difficult to correlate specific levels to specific risks. This is because there are vast differences in genetics and metabolism of alcohol by both the pregnant parent as well as the developing fetus. In fact, the risk may be different even in the same pregnant parent in different pregnancies for this reason.

We do know that alcohol exposure is a leading cause of intellectual disability and puts the developing baby at risk for Fetal Alcohol Spectrum Disorder (FASD). The risks for occasional use of lower amounts of alcohol are not as clear due to ethical issues surrounding conducting clinical research on this topic as well as recall bias. Therefore, every health and obstetric agency strongly recommends against alcohol consumption in pregnancy.

If you were unaware that you are pregnant and consumed alcohol, the best thing to do would be to speak to your OB and/or call a teratology information service such as Mother 2 Baby in the US. While there is no known safe amount of alcohol, a single drink is unlikely to cause a problem. The best thing you can do for your baby is to avoid further use of alcohol during your pregnancy.

Alcohol in breastfeeding

Generally, the same amount of alcohol that enters into your bloodstream makes it into your breast milk. So if your BAC (Blood Alcohol Concentration) is 0.08%, your breastmilk would also contain around 0.08% alcohol. The amount of alcohol that a nursing infant would be exposed to through breast milk is approximately 5–6% of the weight‐adjusted maternal dose. You often see the 5% number thrown around to imply that only 5% gets into breastmilk — but as you can see above, that is very misleading.

Pumping and dumping is not necessary. This is because the breast barrier is dynamic and once it is out of blood systemic circulation of the nursing parent, it is out of breastmilk. Unlike urine, which stores substances in the bladder, alcohol is not trapped in breast milk, but is constantly removed as it diffuses back and forth into the bloodstream.

Because alcohol follows zero order kinetics, the more you drink, the slower it leaves your system and the longer it would take to fully clear the alcohol.

Motherisk did a study to calculate how long it takes for alcohol to leave breast milk — see link below. It is a time-concentration study based on number of drinks and the weight of the nursing parent. If you look at the chart, drinking two drinks takes around 4hrs for a 175lb woman to completely clear alcohol from breast milk and that number is 5 hrs for a 120lb woman. This is provided you are drinking on an average rate and not binge drinking.

The study results by Motherisk is consistent with the new AAP (American Academy of Pediatrics) recommendations of waiting 4hrs after your last drink. I do wish they clarified that this is for moderate drinking, but their wording is ambiguous. It would take considerably much longer for alcohol to be cleared from breastmilk if one were drinking multiple drinks in a short period of time.

The issue is that babies cannot metabolize alcohol properly. It’s takes them 2–3x longer to metabolize vs adults. In addition, the newborn baby’s brain continues to grow in infancy. We simply don’t have enough data to suggest what affects these small amounts of alcohol could have on the growing brains of infants. However, some reports found that babies whose nursing parent drink alcohol while breastfeeding have a decrease in overall feeding by 23% and may also experience changes in their sleeping patterns. One study suggested problems with motor development following exposure to alcohol in breast milk, but other studies did not show the same results.

There is NO basis to the common saying that if you’re sober enough to drive/hold baby, then you’re sober enough to nurse. It’s entirely untrue. Nursing parents should wait a minimum of 4 hours after their last drink, provided it is moderate levels of drinking and not binge drinking.

There is no scientific evidence to support the popular woo that drinking beer (or any other type of alcohol) boosts your milk supply. For most, it would have the opposite effect. Alcohol causes dehydration, which can negatively impact how much milk you make. Also, drinking alcohol disrupts the hormones that are involved in milk production.

Be prepared:

1- Leave expressed fresh or frozen breastmilk that can be fed to the baby. Always leave more than you think is necessary, as baby could be hungrier or you can end up drinking more than you initially expected

2- Caring for an infant while intoxicated is not safe. Drinking alcohol could impair a caregiver’s judgement and ability. If you intend on drinking heavily, your can prep ahead of time and have a sober adult, such as a grandparent or family member, to care for the infant.

3- If you are engorged and in pain while drinking, you can express or pump some milk to relieve the pressure. Do not feed your infant this milk, instead discard immediately.

Also, remember the units of alcohol. 1 alcoholic drink is described as:

- 12 ounces of 5% beer

- 8 ounces of 7% malt liquor

- 5 ounces of 12% wine

- 1.5 ounces of 40% (80 proof) liquor

Remember this depends on the % alcohol content by volume (ABV), which varies even within the same class of alcohol.

Effect of Food:

Food slows down the absorption of alcohol, so it can lower BAC. Hence if you drink on an empty stomach, you get a higher BAC and a lot quicker as well.

In terms of elimination, when you drink while eating, you aren’t saturating the enzymes as quickly as if you were drinking on an empty stomach. At lower alcohol concentrations, the body actually doesn’t follow zero order kinetics but more Michaelis-Mentin (ie all the enzymes are saturated with all the alcohol and so metabolism is at its highest). And of course, eating does also increase blood flow to the liver. But once you move to zero order kinetics, which is fairly quick, then food has no real impact on elimination but will still have an impact on absorption as outlined above.

Disclaimer

The information provided in this article is not intended and should not be construed as medical advice. In addition, the information provided is not a substitute for professional medical expertise or treatment, please see your health care provider if you have any concerns or questions.