Alcohol and Motherhood
by Carol Huotari
CBI Reference Librarian
From: LEAVEN, Vol. 33 No. 2, April-May 1997, pp. 30-1
We provide articles from our publications from previous years for reference for our Leaders and members. Readers are cautioned to remember that research and medical information change over time
Most expectant mothers know that drinking alcoholic beverages is not recommended during pregnancy. Her health care provider, radio, television, magazines, posters in health clinics, even warnings on alcoholic beverage containers caution her. In fact, laws in some countries require merchants to post warning signs wherever alcohol is sold. In the unlikely event that a pregnant woman forgets that alcohol could harm her unborn child, concerned friends and relatives would be quick to remind her.
The case is not nearly as clear-cut after baby has arrived and the mother is breastfeeding. Traditionally beer and, to a lesser degree, wine have been recommended as helpful in the making of milk--a source of B vitamins as well as a means to help a new mother to relax. Actually, it is only the non-pasteurized European beers that contain the beneficial B vitamins, and these are abundant in many foods and food supplements.
Research on breastfeeding and alcohol is admittedly far from conclusive, and at times, even contradictory.
Julie Mennella and Gary Beauchamp of the Monell Chemical Senses Center in Pennsylvania, USA have done research on the effects of alcohol on the nursing baby. They found that the odor of a mother's milk changes with her ingestion of alcohol. The baby suckles more vigorously but takes in less milk on average. It is interesting that the mothers in this study did not perceive this reduction in intake, even though the babies consumed significantly less milk.
Mennella and Beauchamp further determined that if a mother consumed nonalcoholic beer, there was no change in the baby's suckling pattern. This indicates that it is not just the odor of the milk that affects the baby, it is the alcoholic component. It is important for a mother to remember that her baby may choose to discontinue a feeding earlier than usual if she has been drinking.
The medical journal Lancet published a letter by G. De Rosa in 1981 describing his efforts to determine whether or not the ingestion of beer or an alcohol solution would alter prolactin secretion in women. Although the study used non-lactating women, he found that the ingestion of beer increased the levels of prolactin in the blood within 30 minutes after it was ingested. Prolactin is the hormone that helps synthesize milk.
Later, in 1988, a study on suckling rats by M. G. Subramanian further defined the effect of alcohol on lactating females. The normal body levels of prolactin did not change when the mothers were given alcohol; however, the suckling-induced level of prolactin was significantly inhibited. Although this study was done on rats, it shows an inhibitory effect of alcohol on the release of prolactin.
Another hormone in mothers' bodies, oxytocin, is also affected by the ingestion of alcohol. Oxytocin governs the milk-ejection reflex, among other things. When a mother hears her baby cry, oxytocin causes her milk to let down. Oxytocin is released by many sensory pathways including vision, touch, smell, hearing or thinking about her infant.
Edgard Cobo, an early researcher of oxytocin, established the normal conditions of the milk-ejecting response. However, when a mother was given one to two grams of ethanol (alcohol), there was a significant reduction of the milk-ejecting response which appeared to be dose dependent. In 1992, V. Coiro studied the effect of ethanol on non-lactating women. Breast stimulation increased the level of oxytocin in the blood stream, but when ethanol was given, the release of oxytocin was inhibited. Although one should always exercise caution when comparing groups with different characteristics, the possibility exists that when a lactating mother consumes a sufficient quantity of alcohol, her milk let-down could be impaired.
In another study examining the effects of lactational alcohol exposure, Gottesfeld and LeGrue used suckling rat pups as their subjects and found long-term deficits in cellular immunity and the nervous system. This indicates sensitivity in early development, at least in rats.
Why consider studies on non-lactating women and rats, you may wonder? This is, in part, the state of the research on this subject. The Subramanian rat study has been referenced by some of the later researchers, lending credence to its findings. Also, it would be unethical to do research like this on human babies. However, the research must be kept in proper perspective. The metabolism of a substance by a lactating mother may be different from the metabolism of non-lactating women and rats.
Effects on Mothers
In general, women have less body fluid and more fat tissue than men and as a result have greater concentrations of alcohol in their blood than men of the same weight after ingesting the same amount of alcohol. Variations in women's weight affect alcohol detoxification, too. Lighter weight women take longer than heavier women to metabolize the same amount of alcohol. Since the adult liver processes alcohol at a constant rate, the more alcohol that is consumed, the longer it takes to clear the alcohol.
Pat Schulte, in a 1995 article in The Journal of Human Lactation, discusses these factors as well as the fact that a woman's menstrual cycle influences her rate of absorption of alcohol. Low levels of estrogen have been associated with higher blood concentrations of alcohol resulting in the potential for a greater degree of intoxication. When a woman is amenorrheic due to breastfeeding, her estrogen levels are low. Generalizing comparisons between non-lactating women and breastfeeding mothers, however, leads to the assumption that a breastfeeding mother who drinks delivers more alcohol to the baby through breastfeeding. Such comparisons and assumptions may not be accurate as some research shows that lactating and non-lactating women process alcohol differently.
An important finding has come from a Brazilian team comparing lactating and non-lactating women and how alcohol is absorbed. When matched for age, size and ethnic group, they found that the lactating women had slower absorption of alcohol than the controls. In addition to the increased time it took for alcohol to be absorbed, the blood levels (which are comparable to the milk levels) of alcohol were significantly lower in the lactating women at last measurement. The rate of ethanol (alcohol) delivery to the liver appears to be different in lactating women, possibly resulting in less ethanol being circulated in the body.
Margaret Lawton of New Zealand was one of the first to show that the elimination of alcohol from the milk is closely related to its elimination from the blood and not affected by breastfeeding or pumping milk. This indicates that there is no benefit to the practice of pumping and dumping one's milk after drinking alcohol other than to allow for the comfort of the mother whose breasts may become engorged if she delays breastfeeding her baby.
As the alcohol clears from a mother's blood, it clears from her milk. The Schulte article provides a table showing the time it takes to metabolize alcohol based on a woman's weight. If a woman weighs 100 lbs. (45 kg.) and has one drink, it will take 3.1 hours to clear her system. If she weighs 160 lbs. (72 kg.), it will take 1.9 hours to clear her system. It is not known whether this information applies to the lactating woman of the same weight as a non-lactating woman because of the research documenting differences in the processing of alcohol. Schulte also states that neither coffee, showers nor fresh air will hasten the process. In another article in that same journal, Philip O. Anderson recommends that mothers wait to breastfeed at least two hours after one drink.
The American Academy of Pediatrics takes a less cautious approach. They place alcohol in the category "Maternal Medication Usually Compatible with Breastfeeding" in their 1994 Transfer of Drugs and Other Chemicals into Human Milk.
LLLI Health Advisory Council member and breastfeeding advocate Jack Newman has expressed concern that nursing mothers are placed under too many restrictions. He points out that breastfeeding mothers already feel many limitations so he prefers not to prohibit alcohol, especially when the research does not support any serious impact on the baby when a mother has only an occasional drink.
Effects on the Baby
The National Institute of Child Health and Human Development along with the Alcoholism and Drug Abuse Institute of the University of Washington, USA sponsored a study published in 1989 on the maternal use of alcohol during breastfeeding and the mental and motor development of the baby at one year. In their study of 400 infants born to members of a health insurance plan, no difference was found in babies' cognitive development scores (Bayley Mental Development Index) when their mothers ingested alcohol. A slight but significant difference was detected in motor development at one year of age in those babies subjected regularly to alcohol.
This study was submitted to LLLI's Health Advisory Council (HAC) for their evaluation of its significance for breastfeeding mothers. One flaw in the study, consistently pointed out by the HAC members and others, was that the breastfeeding group included babies who received up to 16 oz. (480 ml.) of formula or supplemental milk per day. Also binge drinking was not adequately taken into consideration. The collective response of the HAC was that LLL's position--a breastfeeding mother's alcoholic drink or two on occasion is not harmful to her baby--was acceptable.
It is important to keep a few things in mind when answering a mother's questions about the use of alcohol while she's breastfeeding.
- The age of the baby is important. A newborn with an immature liver will be more easily affected than an older baby.
- The size of the woman could have a bearing on how her system processes alcohol. Likewise, the amount of alcohol she consumes is relevant. Diluting a glass of wine and sipping it slowly is one way to limit intake. It is also common to see people choose the new bottled waters or soda water, sometimes with lemon added. Eating while drinking decreases the rate of absorption. High-fat foods, in particular, delay the absorption of alcohol.
- Alternatives can be considered. A mother can choose a non-alcoholic beverage. If she does choose alcohol, she can wait for the alcohol to clear her system before nursing her baby. This works well if her baby is sleeping through the night. If she becomes engorged, she can pump her breasts as a means to comfort. She can plan ahead and have expressed breast milk stored for the occasion. She should feel confident breastfeeding her baby if her intake was minimal, rather than subject her baby to the alternative of artificial baby milk. There are documented hazards connected with infant formula, but no research proves there is harm to a breastfeeding baby if his mother has a glass of wine at a wedding!
Since current research does not show that occasional use (1-2 drinks) of alcohol is harmful to the nursing baby, La Leche League continues to support the opinion that occasional use of alcohol in limited amounts is compatible with breastfeeding.
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