一个未公开的秘密: 母乳喂养对母亲的益处

Alicia Dermer, MD, IBCLC
Old Bridge NJ USA
From: NEW BEGINNINGS, Vol. 18 No. 4, July-August 2001, p. 124-127

Very few people are unaware of the benefits of breastfeeding for babies, but the many benefits to the mother are often overlooked or even unknown. From the effect of oxytocin on the uterus to the warm emotional gains, breastfeeding gives a mother many reasons to be pleased with her choice. These documented effects are outlined in this excerpt from Breastfeeding Annual International 2001, a recently published anthology which was edited by Dia Michels, co-author of the classic breastfeeding advocacy book, Milk, Money, and Madness. Both books are available from LLLI.
很少人不知道母乳喂养对婴儿的益处,但母乳喂养对母亲的好处却常常被忽略、甚至不为人知。从催产素促进子宫收缩到充满强烈情感的母婴关系,母乳喂养让妈妈有很多理由为自己的选择感到高兴。在最近出版的《2001年国际母乳喂养年度文集》中,摘录了已发布的母乳喂养对母亲的好处。该文集由经典的母乳喂养宣传书籍《牛奶、金钱与疯狂》的共同作者Dia Michels编辑。这两本书都可以从国际母乳会获得。

One of the best-kept secrets about breastfeeding is that it‘‘s as healthy for mothers as for babies. Not only does lactation continue the natural physiologic process begun with conception and pregnancy, but it provides many short and long-term health benefits. These issues are rarely emphasized in prenatal counseling by health care professionals and all but ignored in popular parenting literature. Let‘‘s look at all the benefits breastfeeding provides   mothers and speculate as to why so few are finding out about them.
关于母乳喂养最不为人知的是,妈妈可以和婴儿一样从中获得健康。母乳喂养不仅仅是延续受孕和怀孕之后的自然生理过程,它还能带来很多短期和长期的健康益处。在专业医护人员提供的产前辅导中很少会强调这些,而且在通常的父母教育类著作中也都被忽略。让我们看看母乳喂养提供给妈妈们那些帮助,也猜测一下为什么很少找到对这些益处的描述。

Physiologic Effects of Breastfeeding
Immediately after birth, the repeated suckling of the baby releases oxytocin from the mother‘‘s pituitary gland. This hormone not only signals the breasts to release milk to the baby (this is known as the milk ejection reflex, or “let-down”), but simultaneously produces contractions in the uterus. The resulting contractions prevent postpartum hemorrhage and promote uterine involution (the return to a nonpregnant state).
母乳喂养对妈妈生理上的影响
从一出生开始,婴儿的反复吸吮让母亲的脑下垂体释放催产素(缩宫素)。这种激素不仅让乳房分泌乳汁给宝宝(即所谓的喷乳反射或“奶来了”),同时也引起子宫收缩。由此产生的收缩防止产后出血,促进子宫恢复(回到非妊娠状态)。

Bottle-feeding mothers frequently receive synthetic oxytocin at birth through an intravenous line, but for the next few days, while they are at highest risk of postpartum hemorrhage, they are on their own. As long as a mother breastfeeds without substituting formula, foods, or pacifiers for feedings at the breast, the return of her menstrual periods is delayed (Lawrence and Lawrence 1999). Unlike bottle-feeding mothers, who typically get their periods back within six to eight weeks, breastfeeding mothers can often stay amenorrheic for several months. This condition has the important benefit of conserving iron in the mother‘‘s body and often provides natural spacing of pregnancies.
奶瓶喂养的妈妈们通常在宝宝出生时会接受点滴静脉注射人工合成催产素,但是在接下来的几天,是产后出血风险最高的时候,她们只能凭自己的力量面对。如果妈妈只有母乳喂养,没有替代的配方奶、食物和奶嘴,她恢复月经的时间常常会延迟(Lawrence and Lawrence 1999),经常可以好几个月没有月经,不像人工喂养的妈妈一般在产后6-8周恢复月经。这种现象对母体保存铁质有重大的好处,而且经常达到自然避孕,保持一定的生育间隔。

The amount of iron a mother‘‘s body uses in milk production is much less than the amount she would lose from menstrual bleeding. The net effect is a decreased risk of iron-deficiency anemia in the breastfeeding mother as compared with her formula-feeding counterpart. The longer the mother nurses and keeps her periods at bay, the stronger this effect (Institute of Medicine 1991).
妈妈身体分泌乳汁所需要的铁量,远小于月经中失血所流失的铁量。实际的好处是母乳喂养的妈妈患缺铁性贫血的风险比配方奶喂养的妈妈低。妈妈母乳喂养时间越长,闭经的时间越长,这方面的益处就越大(Institute of Medicine 1991)。

As for fertility, the lactational amenorrhea method (LAM) is a well-documented contraceptive method, with 98 to 99 percent prevention of pregnancy in the first six months. The natural child-spacing achieved through LAM ensures the optimal survival of each child, and the physical recovery of the mother between pregnancies. In contrast, the bottle-feeding mother needs to start contraception within six weeks of the birth (Kennedy 1989).
至于生育能力,哺乳闭经法(LAM)是被充分证明了的避孕方法,在产后头6个月有98%-99% 的避孕成功率。通过哺乳闭经法实现自然避孕,确保每个孩子得到最佳的生存保证,以及妈妈在两次怀孕之间体力的恢复。与此相比,配方奶喂养的妈妈就必须在产后6周内开始实施有效的避孕方法。(Kennedy 1989)

Long-Term Benefits of Breastfeeding
It is now becoming clear that breastfeeding provides mothers with more than just short-term benefits in the early period after birth.
母乳喂养的长期益处
目前确定的是:母乳喂养给妈妈带来的长期益处比仅在出生后获得的短期益处要多得多。

A number of studies have shown other potential health advantages that mothers can enjoy through breastfeeding. These include optimal metabolic profiles, reduced risk of various cancers, and psychological benefits.
有些研究已表明,通过哺乳,妈妈们可以享受其他潜在的健康优势,包括最佳状况的新陈代谢、降低数种癌症的风险以及心理上的益处。

Production of milk is an active metabolic process, requiring the use of 200 to 500 calories per day, on average. To use up this many calories, a bottlefeeding mother would have to swim at least 30 laps in a pool or bicycle uphill for an hour daily. Clearly, breastfeeding mothers have an edge on losing weight gained during pregnancy. Studies have confirmed that nonbreastfeeding mothers lose less weight and don‘‘t keep it off as well as breastfeeding mothers (Brewer 1989).
生产乳汁是一个活跃的代谢过程,平均每天消耗200-500卡路里。要消耗同样多的能量,一个配方奶喂养的妈妈必须每天在游泳池来回游30圈以上,或者骑自行车爬坡一个小时。很明显,母乳喂养的妈妈在消耗孕期存储的脂肪上更有优势。研究也发现,和母乳喂养妈妈相比,非母乳喂养的妈妈减掉的体重更少,并且更难保持(Brewer,1989年)。

The above finding is particularly important for mothers who have had diabetes during their pregnancies. After birth, mothers with a history of gestational diabetes who breastfeed have lower blood sugars than nonbreastfeeding mothers (Kjos 1993). For these women who are already at increased risk of developing diabetes, the optimal weight loss from breastfeeding may translate into a decreased risk of diabetes in later life.
以上的发现对那些孕期患有糖尿病的妈妈尤其重要。分娩后,曾患有妊娠糖尿病的哺乳妈妈,比不哺乳妈妈的血糖水平更低(Kjos,1993年)。而对那些患糖尿病风险已经在增加的妈妈们,由于母乳喂养带来的最大体重减轻可能使后续患糖尿病的风险下降。

Women with Type I diabetes prior to their pregnancies tend to need less insulin while they breastfeed due to their reduced sugar levels. Breastfeeding mothers tend to have a high HDL cholesterol (Oyer 1989). The optimal weight loss, improved blood sugar control, and good cholesterol profile provided by breastfeeding may ultimately pay off with a lower risk of heart problems. This is especially important since heart attacks are the leading cause of death in women.
在怀孕前患有I型糖尿病的女性,在哺乳期常需要的胰岛素更少,因为她们的血糖水平会下降。而且母乳妈妈往往具有较高的高密度脂蛋白胆固醇(Oyer,1989年)。由哺乳带来的最大体重的降低、经改善的血糖水平和好的胆固醇状态,最终会降低心脏问题的风险。这一点尤其重要,因为心脏病突发是妇女死亡的首要原因。

Another important element used in producing milk is calcium. Because women lose calcium while lactating, some health professionals have mistakenly assumed an increased risk of osteoporosis for women who breastfeed. However, current studies show that after weaning their children, breastfeeding mothers‘‘ bone density returns to prepregnancy or even higher levels (Sowers 1995). In the longterm, lactation may actually result in stronger bones and reduced risk of osteoporosis. In fact, recent studies have confirmed that women who did not breastfeed have a higher risk of hip fractures after menopause (Cummings 1993).
另一个产生乳汁所需要的重要元素是钙。由于妇女泌乳时会引起钙的流失,一些健康专业人士误认为哺乳会使妇女患骨质疏松的风险增加。然而,目前的研究表明,当孩子断奶之后,哺乳妈妈的骨密度水平会恢复到和孕前相同甚至更高的水平(Sowers,1995年)。从长期来看,沁乳可能使骨骼更强壮和降低骨质疏松的风险。事实上,最近研究已经证明,没有哺乳过的妇女绝经后髋部骨折的风险更高(Cummings,1993年)。

Non-breastfeeding mothers have been shown in numerous studies to have a higher risk of reproductive cancers. Ovarian and uterine cancers have been found to be more common in women who did not breastfeed. This may be due to the repeated ovulatory cycles and exposure to higher levels of estrogen from not breastfeeding. Although numerous studies have looked at the relationship between breastfeeding and breast cancer, the results have been conflicting. This is largely due to flaws in study design and lack of uniform definition of breastfeeding, resulting in difficulty comparing the data. (In some studies, breastfeeding has been defined as having breastfed at least once a day, while in others it is defined as exclusive breastfeeding, using no supplements or artificial nipples.) Despite this, it is now estimated that breastfeeding from six to 24 months throughout a mother‘‘s reproductive lifetime may reduce the risk of breast cancer by 11 to 25 percent (Lyde 1989; Newcomb 1994). This phenomenon may also be due to suppressed ovulation and low estrogen, but a local effect relating to the normal physiologic function of the breast may also be involved. This was suggested by a study in which mothers who traditionally breastfed on only one side had significantly higher rates of cancer in the unsuckled breast (Ing, Ho, and Petrakis 1977).
没有母乳喂养的母亲已经在众多研究中被证明有更高的患生殖系统癌症的风险。卵巢癌和子宫癌已经被发现在没有母乳喂养的妇女中更常见。这可能是由于反复的排卵周期和不哺乳造成的高雌激素水平。虽然有很多研究讨论母乳喂养和乳腺癌之间的关系,但结果是相互矛盾的。这主要是由于研究设计的缺陷和缺乏母乳喂养的统一定义,所以结果很难相互比较。(一些研究中定义母乳喂养是一天至少一次哺乳,而其他的则定义为完全以乳房哺喂,不使用任何其他补充食物和橡胶乳头。)尽管如此,还是可以推论出在母亲的生育期中有6-24个月的母乳喂养将降低患乳腺癌的风险11-25个百分点(Lyde,1989年;Newcomb,1994年)。这一现象可能由于哺乳抑制排卵和保持较低的雌激素水平,但与乳房的正常生理功能的局部影响也可能有关。一项对传统上只用一边乳房喂养的妈妈进行的研究指出,没有喂奶的一边有较高的患癌风险(Ing,Ho,和Petrakis,1977年)

In two studies, there appeared to be an increase in flare-ups of rheumatoid arthritis in breastfeeding mothers (Jorgensen 1996; Brenna 1994). However, in another study, overall severity and mortality of rheumatoid arthritis was worse in women who had never breastfed (Brun, Nilson, and Kvale 1995). There have been no other studies showing any detrimental health effects to women from breastfeeding. Bottom line: Breastfeeding reduces risk factors for three of the most serious diseases for women-female cancers, heart disease, and osteoporosis-without any significant health risks.
在两项研究中发现哺乳妈妈患类风湿性关节炎有所增加(Jorgensen,1996年;Brenna,1994年)。但另一项研究表明,整体来看类风湿性关节炎的严重程度和死亡率,从未哺乳过的妇女结果更糟(Brun,Nilson和Kvale,1995年)。再无其他研究表明哺乳对妇女有不利健康的影响。所以最基本的,哺乳可以减少三项严重疾病的风险:女性癌症、心脏病和骨质疏松症,而不会增加其他健康风险。

Psychological Issues for Breastfeeding Mothers
How do you measure the peace of mind of having a healthy baby who is developing optimally? Where do you factor in the financial burden of formula prices and increased medical costs?
母乳妈妈的心理获益
如何衡量由于拥有一个健康的宝宝且成长良好而带来的心态的平和的价值?如何估算配方奶支出和医疗支出不断上涨的财务压力所带来的影响?

Public health agencies advocate for breastfeeding because of its well-documented health advantages to babies, but they fail to convey to individual mothers and families the potential emotional impact of this very crucial infant-feeding decision. In Western society, the decision about breast or bottle is still seen very much as a personal choice based on convenience. The potential stress of living with a child with recurrent illnesses, or the loss of the unique bond that comes from breastfeeding, are often omitted from the decision-making process.
公共卫生机构提倡母乳喂养,因为已被证实的母乳喂养婴儿的健康优势,但他们没有向母亲和家庭传递这个具有决定性的婴儿喂养选择所带来的情感作用。在西方社会,母乳喂养还是人工喂养仍被视为是基于便利性考虑的个人选择。因孩子反复生病和失去只有母乳喂养才能带来的独特亲子连接导致的潜在压力,却常常在决定过程中被忽略。

There is much more to breastfeeding than the provision of optimal nutrition and protection from disease through mother‘‘s milk. Breastfeeding provides a unique interaction between mother and child, an automatic, skin-to-skin closeness and nurturing that bottle-feeding mothers have to work to replicate. The child‘‘s suckling at the breast produces a special hormonal milieu for the mother. Prolactin, the milk-making hormone, appears to produce a special calmness in mothers. Breastfeeding mothers have been shown to have a less intense response to adrenaline (Altemus 1995).
除了母乳所提供的最佳营养和免疫保护,母乳喂养还有更多益处。哺乳提供了一种独有的母亲和婴儿之间的互动,一种自发的肌肤贴着肌肤的亲密和滋养。而人工喂养的妈妈必须格外努力来复制这一过程。孩子吮吸乳房令妈妈产生一种特别的激素环境。催乳素,促进乳汁分泌的激素,可以让母亲特别地平静。母乳喂养妈妈被证实面对肾上腺素的刺激,更少引起激烈的反应(Altemus,1995年)。

This calming effect is hard to measure in a society largely unsupportive of breastfeeding such as the United States, where breastfeeding beyond the early weeks is not the norm. Mothers who try to breastfeed in this climate often experience physical and emotional problems. These problems result from a lack of breastfeeding role models among family and friends, and are compounded by the easy availability of formula and a lack of access to knowledgeable and supportive health care professionals.
在一个大多数人不支持母乳喂养的社会,例如美国——母乳喂养超过最初几周是不常见的,这种平静的情绪效果很难衡量。在这种氛围下尝试哺乳的母亲常常遇到身体和情绪的问题。这些问题源于家庭和朋友中缺少母乳喂养的榜样,而太容易获得配方奶粉以及缺少具有知识和支持性的医疗保健专业人士也加剧了这种情况。

Even if a mother overcomes physical problems, she may still encounter negative comments, such as “Are you still nursing?” or “Your milk may not be strong enough-why don‘‘t you add formula?” Or her employer may make it impossible for her to continue breastfeeding on returning to work. Or she may be harassed for breastfeeding in public. No wonder that few mothers get to fully experience the relaxing effects of breastfeeding.
即使一个妈妈克服了身体问题,她可能还会遇到很多负面评价,例如“你还在喂奶吗?”、“你的奶已经不够营养了,为什么不加点配方奶呢?”或者当她回到工作岗位后,雇主可能使她无法继续母乳喂养。又或者当她在公共场所哺乳时,可能受到骚扰。难怪很少有母亲充分体验到母乳喂养对情绪的放松作用 。

New motherhood is a time fraught with emotion. The baby blues are common, often exacerbated by lack of support and a sense of isolation. The role of breastfeeding in postpartum emotional upheavals has not been well studied, but breastfeeding mothers with depression need treatment just as much as any other mother. Such women present a unique challenge to health care professionals. Since medications may pass into breast milk, many physicians believe the safest solution is to wean the child. However, in most cases of depression, women do better if they continue to breastfeed. Unfortunately, too often physicians insist that mothers wean their child in order to take antidepressant medicines.
做新妈妈的日子充满情绪的斗争。产后抑郁很常见,而且由于缺少支持和孤独感而加剧。在产后的情绪动荡期间,母乳喂养的作用还没有得到很好的研究,但是母乳喂养的母亲患抑郁症需要治疗的情况跟其他母亲一样。这些妈妈给医疗保健专业人士带来了独特的挑战。因为药物可能进入乳汁,所以很多医生相信最安全的方式就是断奶。但是在多数抑郁的情况中,妈妈们只要继续哺乳就会复原得快。可惜太多医生坚持妈妈需要断奶来服用抗抑郁药物。

A review of the literature, however, has demonstrated that several antidepressants pose minimal, if any, risk to the nursing child. A mother who feels that her nursing relationship with her child is the only thing going right in her life can now continue to breastfeed while receiving appropriate medications for her depression.
然而文献显示,已经证实一些抗抑郁药物,即使有影响乳儿的风险,机会也很少。在妈妈服用抗抑郁药物期间,当她感觉到与宝宝建立的喂养关系是她生活中唯一正确的事情,那她可以继续母乳喂养。

Why Don‘‘t More People Know How Good Breastfeeding Is?
Clearly, breastfeeding is good for mothers both physically and emotionally. And yet, many mothers decide to breastfeed based solely on the benefits to the baby. Breastfeeding in the context of a bottle-feeding society tends to be perceived as inconvenient and uncomfortable.
为什么没有更多人了解母乳喂养的好处?
很明显,母乳喂养对妈妈的身心健康都有益处。但是很多妈妈决定母乳喂养是基于对宝宝的好处。在一个以奶瓶喂养为主的社会,母乳喂养被看做是不方便和不舒服的。

Often, mothers see breastfeeding as martyrdom to be endured for their baby‘‘s health. If they stop early, they may feel guilty about depriving the baby of some health benefits, but their guilt is often soothed by well-meaning people who reassure them that “The baby will do just as well on formula.” Perhaps if they knew that continuing to breastfeed is also good for their own health, some mothers might be less likely to quit when they run into problems.
通常,妈妈们把母乳喂养看做为了宝宝健康的而作出的一种牺牲。如果她们过早断奶,可能为剥夺了一些宝宝健康的好处而感到内疚。但这些内疚常常得到好心人的安慰说“配方奶也对宝宝很好。”如果她们知道继续母乳喂养对她们自己的健康也有好处,也许有的妈妈在遇到问题时就不会选择断奶了。

Many mothers are not being told how good breastfeeding is for their health. Whether out of ignorance or due to the influence of the artificial baby milk industry, many health care providers fail to inform mothers of the facts. It‘‘s time for this well-kept secret to come out. As word spreads about these little-known facts, more mothers will not merely choose to breastfeed briefly to provide early disease protection for their baby, but will continue to breastfeed, providing optimal outcomes both for their children and for themselves.
多数妈妈没有被告知母乳喂养对她们自己身体的好处。无论是因为无知还是受到婴儿配方奶行业的影响,很多医疗保健人员没有给妈妈们提供事实真相。现在应该让这个秘密得到公开了。如果这个鲜为人知的事实得到广泛传播,会有更多妈妈不仅为了给宝宝提供早期疾病防护而进行短暂的母乳喂养,还会继续哺乳下去,为自己和宝宝获取最多益处。

Alicia Dermer, MD, IBCLC, is Clinical Associate Professor in the Department of Family Medicine at the University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School in New Brunswick, New Jersey. She has a special interest in wellness and health promotion. As part of this interest, she has gained expertise in breastfeeding education and promotion. She successfully sat for the certifying examination of the International Board of Lactation Examiners in 1995. She lectures extensively on the subject of lactation, is actively involved in health care professional and lay education about breastfeeding, and has several publications on the subject.
Alicia Dermer, MD, IBCLC,在新泽西州新不伦瑞克的罗伯特•伍德•约翰逊医学院、新泽西医学和牙科大学的家庭医学部任临床副教授。她对促进健康和保健方面有特别的兴趣。作为这个兴趣的一部分,她已经获得了母乳喂养的教育和宣传方面的专业知识。她在1995年成功参加国际沁乳顾问资格考试委员会的认证考试。她广泛讲授和哺乳有关的课题,积极参与有关母乳喂养方面的健康专业及非专业的教育,还出版了几本这方面的书。

(黄寅 翻译,Shiuh-jane、Daisy审稿)

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