By Colleen Hurley, RD, Certified Kid’s Nutrition Specialist
A common worry for breastfeeding mothers is knowing when your baby has had enough to 
eat. Just like babies let you know when they are hungry; they typically stop eating when they are full. This has also been touted as one of the many benefits of breastfeeding because it prevents over-feeding which can lead to weight problems later in life. Traditionally, advice had been aimed at limiting the amount of a time a baby nurses. Yet over the past several years, recommendations have shifted to allowing the baby to dictate how long and when feedings take place. New research, however, has found that shorter breastfeeding time may be more beneficial for the baby.
The baby-led method of breastfeeding allows the baby to feed for as long as she needs from the first breast and that switching breasts during feeding is not necessary. Dr. Anne Walshaw and colleagues discovered that regular feedings at 10 minute intervals on each breast resulted in both a higher rate of breastfeeding and increased weight gain. Midwives warn this method is not a one size fits all approach.
Why would increased weight gain be beneficial? Researchers noted a significant decrease in weight gain in breastfed babies after the baby-led method became more common. Observing 63 mothers who exclusively breastfed, Walshaw and associates divided the women into 2 groups. The first group was instructed to feed their babies for a maximum of 10 minutes on each breast about every 3 hours throughout the day as well as at night if needed. The rest of the mothers were told to feed their babies as they wanted and to only offer the second breast if the babies appeared to be still be hungry.
It turns out, three quarters of the mothers who followed the traditional method of about 10 minute feedings per breast were still nursing at 12 weeks while less than half of the mothers from the baby-led method group continued to nurse. In addition, babies who were fed for around 10 minutes from the breast had increased weight gain during the first 6-8 weeks of life. While the results may seem counterintuitive, researchers conclude that extending nursing time can actually interrupt a mother’s internal system for milk production.
Release of the hormone oxytocin is necessary to trigger a mother’s “let down” reflex, which sends the milk from the breast cells to the nipple. When babies stay on a breast for too long, oxytocin production is disrupted. Also, if babies to do not nurse on the second breast, which is full of milk, a protein is produced that signals the mother’s body to stop producing milk. This process can alter the feeding process for several hours, possibly days. The researchers conclude babies feeding from both breasts actually receive more milk and the shorter feeding times can lead to increased weight gain and other positive benefits.
译文:
英国婴幼儿发展研究会发现短时间哺乳对婴儿最佳
婴儿营养鉴定专家柯林·赫尔利·RD表示，哺乳期的母亲们一个普遍的困惑就是不知道什么时候婴儿已经吃饱了。正如婴儿们饿的时候会哭着让你知道，当他们饱了也就自然会停止吮吸了。这也是喂哺乳喂养的一个好处，以防婴儿过度进食而导致日后体重问题的出现。传统上来说，一般会建议母亲缩短婴儿的进食时长。然而在过去几年，这种观点发生了改变，母亲被建议让婴儿自己来决定什么时候进食以及进食多久。然而，新的研究表明，哺乳时间越短对婴儿越有利。
哺乳中的婴儿主导法赞成让婴儿自由进食而不要打断他们，母亲给婴儿喂奶时也没有必要交替乳房。安·沃尔什博士和他的同事发现，如果让婴儿在母亲的每个乳房分别吮吸十分钟，那么哺乳的频率就会增加，婴儿的体重也会增加。助产士警告，这种方法并不是时时适用。
为什么不断增加的体重是有益的呢？研究员表示，在婴儿主导法渐渐普及后，哺乳喂养的婴儿体重有了很大的下降。对63位进行母乳喂养的母亲进行观察之后，沃尔什和他的同事把她们分成了2组。第一组的母亲在白天每隔三个小时就给婴儿喂奶一次，一次喂奶最多十分钟，如果晚上有需要也会给婴儿喂奶。剩余的母亲被告知当婴儿想要吃奶的时候就喂他们，只有当婴儿又饿的时候才再次喂他们。
结果显示，在用传统的十分钟喂奶一次方法的母亲中，有四分之三的母亲在十二周的时候仍就在喂奶，而超过一半的遵循婴儿主导法喂奶的母亲在十二周的时候已经能停止哺乳了。另外，十分钟进食一次的婴儿在出生后最初的6-8周时间里体重有了增加。虽然结果很出乎意料，研究者们给出了一个结论：实际上，因为要制造乳汁，过长的哺乳时间会扰乱一位母亲身体的内部系统。
母亲的乳汁释放反射必须要有荷尔蒙后叶催产素的参与，这种反射让奶水由乳房细胞积聚到乳头。当婴儿吮吸过久，后叶催产素的生成就会出现混乱。而且，如果婴儿不在另外一个充满乳汁的乳房上吮吸，那么就会产生一种蛋白质，这种蛋白质给母亲的身体发出停止生产乳汁的信号。这个过程会改变哺乳程序，短则几个小时，长则几天。研究者总结到：用两边乳房喂奶实际上能让婴儿得到更多的乳汁，哺乳次数越少婴儿的体重越能增加，同时还会有很多积极的影响，让婴儿受益。