Breastfeeding

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A breastfeeding infant

Breastfeeding is the practice of a human mother feeding a baby (and sometimes a toddler or a young child) with milk produced from her mammary glands, usually directly from the nipples. Babies have a sucking instinct allowing them to extract the milk.

While many mothers choose to breastfeed their child there are some who do not, either for personal or medical reasons. Breast milk has been shown to be very beneficial for a child, though, as with other bodily fluid transfers, some conditions can be passed from the mother to the infant. As an alternative the baby may be fed infant formula until the time that the child may move on to baby food.

Beginning lactation

File:Breastfeeding(milkfinal).png
When the baby sucks, a hormone called oxytoxin starts the milk flowing from the alveoli, through the ducts (milk canals) into the sacs (milk pools) behind the areola and finally into the baby's mouth

Main article: Breast milk

Throughout pregnancy a woman's body produces hormones which stimulate the growth of the milk duct system in the breasts:

By the fifth or sixth month of pregnancy, the breasts are sufficiently developed to produce milk. Near the time of birth, the breasts may begin to secrete a thick, yellowish fluid called colostrum (or "beestings"), which is the first milk the infant receives. It contains important antibodies from the mother's body providing immunological protection. Colostrum has no fat and little sugar – these substances appear three to four days after birth when the suckling action of the infant further stimulates the breast to produce mature breast milk.

After the colostrum the breast produces milk on a basis of supply and demand in response to how often a child feeds and how much milk he or she consumes. The production, secretion and ejection of milk is called lactation. Some breastfeeding advisers recommend at least one feeding every four hours to prevent premature termination of lactation.

The exact integrated properties of breast milk are not entirely understood, but the nutrient content after this period is relatively consistent and draws its ingredients from the mother's food supply. If that supply is found lacking, content is obtained from the mother's bodily stores. The exact composition of breast milk varies from day to day, depending on food consumption and environment, meaning that the ratio of water to fat fluctuates. Foremilk, the milk released at the beginning of a feed, is watery, low in fat and high in carbohydrates relative to the creamier hindmilk which is released as the feed progresses. The breast can never be truly "emptied" since milk production is a continuous biologic process.

The let-down reflex

The let-down reflex, also known as the milk ejection reflex, is the stimulation of the muscles of the breast to squeeze out the milk by the release of the hormone oxytocin. Breastfeeding mothers describe the sensation differently, with some feeling slight tingling and others not feeling anything different.

The reflex is not always consistent, especially at the start of the breastfeeding process. The thought of nursing or the sound of any baby can stimulate the process causing unexpected leakage. Commonly both breasts can give out milk when one infant is feeding, but this and other problems often settle after two weeks of feeding. One major cause of difficulties during breastfeeding is when the mother is in a stressed or anxious state of mind.

Causes of a poor let-down reflex:

  • Sore or cracked nipples
  • Separation from the infant
  • A history of breast surgery

When a mother has difficulties breastfeeding they may try different methods of assisting the let-down reflex, including:

  • Feeding in a familiar and comfortable location
  • Massage of the breast or back
  • Warming the breast with a cloth or shower

Benefits

The benefits of breastfeeding are both physical and psychological. Nutrients and antibodies are passed through to the baby and the process of breastfeeding releases hormones into the womans system. The bond between the baby and its mother is also strengthened during breastfeeding.

Benefits for the infant

Breast milk consumption has been linked to a decreased risk for several infant conditions including Sudden Infant Death Syndrome (SIDS). The sucking technique required of the infant encourages the proper development of both the teeth and other speech organs.

Numerous health benefits of breastfeeding have been medically documented. According to the American Academy of Pediatrics' policy statement on breastfeeding and the use of human milk, "Extensive research, especially in recent years, documents diverse and compelling advantages to infants, mothers, families, and society from breastfeeding and the use of human milk for infant feeding. These include health, nutritional, immunologic, developmental, psychological, social, economic, and environmental benefits."[1]

Breast milk helps to lower the risk of or protect against:

Benefits for the mother

Breastfeeding has also been shown to be beneficial to the mother. The act of breastfeeding releases hormones which have been found to both relax the mother and cause her to experience nurturing feelings toward her infant. Breastfeeding as soon as possible after giving birth increases levels of oxytocin which encourages a more rapid contraction of the uterus and in turn decreases postpartum bleeding. Breastfeeding can also allow the mother to return to her pre-pregnant weight as the fat stores accumulated during pregnancy are utilized in milk production. Frequent and exclusive breastfeeding delays the return of menstruation and fertility (known as lactational amenorrhea) allowing for improved iron stores and the possibility of natural child spacing. Breastfeeding mothers experience improved bone re-mineralization postpartum, and a reduced risk for both ovarian and pre-menopausal breast cancer.

Bonding

The maternal bond is strengthened through breastfeeding, with the hormonal releases giving the mother positive feelings of nuture towards the child. Building upon this bond is very important as studies show that up to 80% of mothers suffer from some form of postpartum depression, though most cases are very mild. The partner can help to support the mother in a variety of ways and is seen as an important factor in successful breastfeeding [2]. This can also help to establish the paternal bond in fathers.

The relationship between the partner and the child can also be greatly affected by the act of breastfeeding. While some partners may feel left out when the mother is feeding the baby others may see the whole process as a chance to bond as a family. Breastfeeding, possibly alongside birth-related health problems, takes a lot of time away from the mother and reduces her ability to perform tasks she might usually undertake. This may add pressure to the partner and the family with them having to work harder whilst also caring for the mother. However, this pressure can help to strengthen the bonds of the family as they are often very willing to show their supportiveness.

After a seperation the father of the baby, if looking after the child away from the mother, may find it inpractical or inappropriate to feed expressed breast milk to the infant. This may remove the choice of the mother of whether to breastfeed her child or not.

Recommendations and research

"Exclusive breastfeeding is ideal nutrition and sufficient to support optimal growth and development for approximately the first 6 months after birth. [...] It is recommended that breastfeeding continue for at least 12 months, and thereafter for as long as mutually desired."

- The American Academy of Pediatrics (AAP) [3]

"A recent review of evidence has shown that, on a population basis, exclusive breastfeeding for 6 months is the optimal way of feeding infants. Thereafter infants should receive complementary foods with continued breastfeeding up to 2 years of age or beyond."

- The World Health Organization (WHO) [4]

"If we allow the 'breast versus bottle' argument to be reduced to a simple issue of nutrition, we ignore the much greater potential breastfeeding has to enhance the lives of parents and children."

- Gill Rapley, deputy programme director of the UNICEF UK Baby Friendly Initiative [5]

Contraindications and complications

It is not uncommon for a mother and child to have difficulties breastfeeding, with some women unable to feed their child at all. Others find it too problematic or choose not to attempt or continue breastfeeding for personal reasons.

Breast refusal

When first born the child must learn how to feed. Though babies have a natural sucking reflex they may occasionally resist feeding from the breast, often due to external factors. It is important for the baby to be fed soon after birth in order to quickly establish the routine and to become accustomed to feeding from the breast. Other causes of breast refusal include:

  • Overhandling after birth
  • Formula feeding, sometimes without the knowledge of the mother.
  • Poor feeding technique
  • The use of artificial teats leading to "nipple confusion"
  • The presence of thrush in the mouth of the baby
  • Distractions or interruptions during feeds
  • Long seperations from the mother
  • Breathing difficulties, often caused by a common cold

In later stages teething is a significant hinderance to breastfeeding and is seen by many as the ideal time to ween the infant.

Medical conditions of the infant

Reasons for the inability of an infant to feed include:

Premature babies have difficulties with an underdeveloped sucking reflex and tiring during feeds.

Medical conditions of the mother

Damage to the breast tissue can cause problems or totally prevent manageable breastfeeding, especially women with history of breast surgery or infection. Cancer (particularly breast cancer) and chemotherapy treatments have also been shown to cause difficulties. Many women with previous surgeries, abscesses and cancer can breastfeed successfully.

Infectious diseases such as HIV, AIDS or active, untreated tuberculosis can be passed onto the infant. A HIV-positive mother breastfeeding an infant can, in some countries, be investigated for child abuse – a 1998 case in the U.S. saw a mother reported to social services for her continued breastfeeding and non-treatment of the child for HIV [6]. The presence of herpes lesions on the breast is also contraindicative to breastfeeding.

Mastitis, the inflammation of the mammary glands caused by the blocking of the milk ducts, can cause painful areas on the breasts or nipples and may lead to a fever or flu-like symptoms.

Negative effects upon the infant

Breastfeeding can be harmful to the infant if the mother:

Health and diet

Since the nutritional requirements of the baby must be satisfied solely by the breast milk in exclusive breastfeeding it is important for the mother to maintain a healthy lifestyle, especially with regards to her diet. This usually involves a high calorie, high nutrition diet which follows on from that in pregnancy. Some breastfeeding advisers suggest mothers avoid certain gas producing food, such as beans, if the baby starts to develop colic or gas.

Breastfeeding mothers must use caution if they regularly consume nicotine through tobacco smoking. In addition to reducing the milk supply, heavy use of cigarettes (more than 20 per day) has been shown to cause vomiting, diarrhea, rapid heart rate, and restlessness in infants. In general, though, nicotine in breast milk is not easily absorbed into the infant's intestinal tract and is quickly metabolized. Research is ongoing to determine whether the benefits of breastfeeding out-weigh the potential harm of nicotine in breast milk. The effects of a smoky environment are thought to have links to Sudden Infant Death Syndrome (SIDS).

Heavy alcohol consumption is known to be harmful to the infant, but there is no consensus on how much alcohol may be safely consumed. It is generally agreed that small amounts of alcohol may be occasionally consumed by a breastfeeding mother. Levels of alcohol in breast milk peak 30 to 90 minutes after one drink of moderate alcoholic content. Considering the known dangers of alcohol exposure to the developing fetus, many medical professionals believe it is prefereable to err on the side of caution with alcohol exposure to a baby and have breastfeeding women restrict their alcoholic intake.

Excessive caffeine consumption by the mother can cause irritability, sleeplessness, nervousness and increased feeding in the breastfed infant. Moderate use (one to two cups per day) usually produces no effect. Breastfeeding mothers are advised to avoid or restrict caffeine intake.

The recreational use of marijuana in conjunction with breastfeeding is a controversial issue. The AAP Committee on Drugs lists marijuana in their table of Drugs of Abuse for Which Adverse Effects on the Infant During Breastfeeding Have Been Reported yet they reference only one study in the literature and this study reports no effect. [7] There is a lack of research on the effects of marijuana on the breastfed infant.

Feeding options and requirements

Exclusive breastfeeding is generally defined as feeding a baby nothing but breast milk. Predominant or mixed breastfeeding is the practice of feeding breast milk along with some form of substitute — infant formula or baby food, depending upon the age of the child.

Exclusively breastfed infants feed, on average, 8–12 times a day. The requirements of each child varies greatly, with newborns consuming in the range of one to three ounces and babies after the age of four weeks consuming around four ounces per feed. Each baby is different and as it grows this amount will increase. It is important to recognise the signs of a baby's hunger and it is advised that the baby should dictate the number, frequency and length of each feed, based on the assumption that it knows the amount of milk it needs. The supply of milk in the breast is determined by the frequency and length of these feeds or the amount of milk expressed.

One criticism of breastfeeding is the difficulty in accurately monitoring the amount of food taken by the baby. This, however, is largely discounted because the baby will feed as per its own requirements.

Expression

Expressed breast milk (EBM) or infant formula can be fed to an infant by bottle

When direct breastfeeding is not possible the baby may still be fed breast milk. By expressing her milk, a mother can allow her child to be fed while she is not present or does not have the opportunity to do so herself. With expression through manual massage or the use of a breast pump the woman can draw out her milk and keep it in a bottle ready for use. This bottle may be refrigerated for up to eight days or frozen for up to four months.

Expression can be used to prolong the lactation when required. This is most common if the mother and child are seperated for an extended period. In cases of the baby being unable to feed expressed milk can be fed through a nasogastric tube.

Some women donate their expressed breast milk (EBM) to other people, either directly or through the hospital. Though some dislike the idea of feeding their own child with another person's milk others appreciate the ability to give their baby the benefits of breast milk.

Infant formula

If the decision is made not to feed the child with breast milk or if it is not possible then infant formula is given to the infant, usually using a baby bottle. While proven inferior to breast milk, infant formula has in recent times been marketed as being a superior feeding-solution. Such marketing has been successful in many areas, with a 2004 UK Department of Health survey showing that 34% of women believe infant formula to be very similar or the same as breast milk. [8]

Infant formula has been heavily marketed and promoted to many new mothers as the preferred option to breastfeeding. In 1979 the International Baby Food Action Network (IBFAN) was formed to help raise awareness of such practices.

Tandem, extended and shared breastfeeding

Feeding two infants simultaneously is called tandem breastfeeding. The most common need for this is after the birth of twins whereby both babies are fed at the same time. It is not necessarily the case, however, that the appetite and feeding habits of both babies are the same. This leads to the complication of trying to feed each baby according to their individual requirements while also trying to breastfeed them both at the same time.

In cases of multiple births with three or more children it is extremely difficult for the mother to organise feeding around the appetites of all of the babies. The mammary glands can produce a high quantity of milk, according to the demand placed upon them, and many mothers have been able to successfully feed their infants [9]. It is common, however, for the woman to look to other alternatives.

Tandem breastfeeding is also convenient if a woman gives birth to a newborn while still feeding an older baby or child. Under these circumstances it is possible for the newborn baby to miss out on the beneficial colostrum.

Although some may find it controversial, some women breastfeed their offspring for as many as three to seven years from birth. This is referred to as extended breastfeeding.

In developing nations within Africa and elsewhere, it is sometimes common for more than one woman to feed a child. This shared breastfeeding has been highlighted as a source of HIV infection amongst infants born HIV-negative [10].

See also: wet nurse

Breastfeeding method

There are many texts available to new mothers to assist in the establishment of breastfeeding. The baby will usually indicate hunger by crying or moaning and fussing. When the baby's cheek is stroked, the baby will move his or her face towards the stroking and open his or her mouth, demonstrating the rooting instinct. Breastfeeding can make the mother thirsty and can last for up to an hour – it is therefore common for the mother to require a drink during the process.

Feeding and positioning

While for some people the process of breastfeeding seems natural there is a level of skill required for successful feeding and a correct technique to use. Incorrect positioning is one of the main reasons for unsucessful feeding and can easily cause pain in the nipple or breast. By tickling the baby's cheek with the nipple the baby will open its mouth and turn toward the nipple, which should then be pushed in so that the baby has a mouthful of nipple and areola – the nipple should be at the back of the baby's throat. Inverted or flat nipples can be massaged to give extra area for the baby to latch onto. Many women choose to wear a nursing bra to allow easier access to the breast than normal bras.

The baby may pull away from the nipple after a few minutes and is ready to start eating from the other side. It takes approximately 10 minutes for the breast to produce the hindmilk and around 30 minutes for the supply to run out.

Since feeding may last as long as an hour it is important for the breastfeeding woman to be comfortable.

  • Upright: The sitting position with the back straight
  • Lying down: Good for night feeds or for those after a caesarean section
    • On her back: Usually sat slightly upright; particularly useful for tandem breastfeeding
    • On her side: The mother and baby lie on their sides
  • Hands and knees: The mother is on all fours with the baby underneath her

There are many positions and ways in which the feeding infant can be held. This depends upon the comfort of the mother and child and the feeding preference of the baby – some babies tend to prefer one breast to another. Most women breastfeed their child in the cradling position.

  • Cradling positions:
    • Cradle hold: The baby is held with it's head in the woman's elbow horizontally across the abdomen, "tummy to tummy", with the woman in an upright and supported position
    • Cross-cradle hold: As above but the baby is held with it's head in the woman's hand
  • Football hold: The woman is upright and the baby is held securely under the mother's arm with the head cradled in her hands
  • Feeding up hill: The baby lies stomach to stomach with the mother who is lying on her back; this is helpful for babies finding it difficult to feed
  • Lying down:
    • On its side: The mother and baby lie on their sides
    • On its back: The baby is lying on it's back (cushioned by something soft) with the mother on her hands and knees above the child

When tandem breastfeeding the mother is unable to move the baby from one breast to another and comfort can be more of an issue. This brings extra strain to the arms, especially as the babies grow, and many mothers of twins recommend the use of more supporting pillows. Favoured positions include:

  • Double cradle hold
  • Double clutch hold
  • One clutched baby and one cradled baby
  • Lying down

Breast and nipple pain

Breastfeeding may hurt some women, sometimes related to an incorrect technique, but usually eases over time. Milk ducts can block up on occasion, leading to breast engorgement, and should be addressed with massage and by encouraging the baby to suck from that side to keep it as empty as possible until the problem goes away.

Fair skinned mothers are most likely to experience cracked nipples, but it can happen to anyone. The baby's rough tongue can also cause grazes and the suction can cause bruising. If breastfeeding is endured for the initial six weeks then this usually becomes easier. Mothers determined to breastfeed their babies can buy or hire breast pumps to extract the milk.

Weaning

Weaning is the process of gradually introducing the infant to what will be its adult diet and withdrawing the supply of milk. The infant is considered to be fully weaned once it no longer receives any breast milk (or bottled substitute) and begins to eat baby food. This often leads to lactose intolerance.

History of breastfeeding

In the early years of the human species, breastfeeding was as common as it was for other mammals feeding their young. There were no alternative foods for the infants, and the mother, along with other lactating females, would have no choice but to breastfeed the children. This process is still seen in many developing countries and is known as shared breastfeeding.

The Egyptian, Greek and Roman empires saw women only feeding the own children. However, breastfeeding began to be seen as something too common to be done by royalty and wet nurses were employed to feed the children of the royal families. This was extended over the ages, particularly in western Europe, and saw women of noble birth (or who married into nobility) making use of wet nurses.

According to some Brahminical literature, breastfeeding in 2nd century India was commonly practiced but not until the fifth day, allowing the colostrum to be discarded and the true breast milk to flow.

Developing alternatives

Alternatives first became popular in the late 15th century with many parents substituting cow or goat's milk for their own breast milk. This was particularly necessary for those families working the land whereby time could not easily be taken out to regularly breastfeed the child. Such trends soon faded when the problems associated with these milks starting to show, and by the mid to late 16th century breastfeeding once again became the preferred feeding method for most families. Italian Hieronymus Mercurialis wrote in 1583 that women generally finished breastfeeding an infant exclusively after the third month and entirely after around 13 months.

Dry nursing, the feeding of flour or cereal mixed with broth or water, became the next alternative in the 19th century but once again quickly faded. Around this time there became an obvious disparity in the feeding habits of those living in rural areas and those in urban areas. Most likely due to the availability of alternative foods babies in urban areas were breastfed for a much shorter length of time, supplementing the feeds earlier than those in rural areas.

Though first developed by Henri Nestlé in the 1860s infant formula received a huge boost during the post World War II "Baby Boom". The aggressive marketing campaigns when business and births decreased saw Nestlé and other such companies focus on non-industrialised countries, while government strategies in industrialised countries attempted to highlight the benefits of breastfeeding.

Breastfeeding in Japan

Traditionally Japanese babies were born at home and breastfed with the help of breast massage. After World War II Western medicine was taken to Japan and the women began giving birth in hospitals, where the baby was usually taken to the nursery and fed formula. In 1974 a new breastfeeding promotion by the government helped to boost the awareness of its benefits and the uptake has seen a sharp increase. Japan became the first developed country to have a Baby-friendly hospital and has since gone on to have another 24 such facilities.

Publicity, promotion and law

The health departments of various governments have recognised the importance of encouraging women to breastfeed. The required provision of baby changing facilities was a large step towards making places more accessible for parents and in many countries there are now laws in place to protect the rights of a breastfeeding mother when feeding her child in public.

The World Health Organisation has played a large role in encouraging these governmental departments to promote breastfeeding. Under this advice they have developed national breastfeeding strategies, including the promotion of its benefits and attempts to encourage mothers, particularly those under the age of 25, to choose to feed their child with breast milk.

Government campaigns and strategies around the world include:

Developing countries

In many countries, particularly those with a generally poor level of health, malnutrition is the majority cause of death in children under 5, with 60% of all those cases being within the first year of life [11]. International organisations such as Plan International and La Lêche League have helped to promote breastfeeding around the world, educating new mothers and helping the governments to develop strategies to increase the number of women exclusively breastfeeding.

Traditional beliefs in many developing countries give different advice to women raising their newborn child. In Ghana babies are still frequently fed with tea alongside breastfeeding [12]. This reduces the benefits of exclusive breastfeeding and the drink can inhibit the absorption of iron, important in the prevention of anemia.

Breastfeeding in public

When in public with a breastfed baby it is often difficult to avoid the need to feed the infant. The public reaction at the sight of breastfeeding can make the situation uncomfortable for those involved. There are numerous laws around the world that have made public breastfeeding legal and companies are not allowed to deny that right.

In the U.S. the "Right to Breastfeed Act" (HR 1848) was signed into law on September 29, 1999 affirming the right of a woman to breastfeed her child anywhere on federal property. However, not all state laws have affirmed the same right in their respective public places. Nowhere is breastfeeding in public illegal.

A survey reported by the UK Department of Health stated that most people (84%) find breastfeeding in public acceptable as long as it is done discreetly [13]. This is contradictory to the 67% of mothers worried about general opinion being against public breastfeeding.

Many mothers choose to purchase pumping equipment or express milk ("milk" themselves) by hand so that they can carry a small bottle of milk with them if they plan to be out at mealtimes. This allows them the advantages of breastfeeding while avoiding possibly uncomfortable situations. Unfortunately, breastfed babies can have trouble transitioning to a bottle, so this may not work for everyone.

Recent global uptake

The following table shows the uptake of exclusive breastfeeding. Sources: WHO Global Data Bank on Breastfeeding and UNICEF Global Database Breastfeeding Indicators

Country Percentage Year Type of feeding
Armenia 20.8% 1997 Exclusive
0.7% 1993 Exclusive
Benin 16% 1997 Exclusive
13% 1996 Exclusive
Bolivia 53% 1994 Exclusive
59% 1989 Exclusive
Central African Republic 4% 1995 Exclusive
Chile 97% 1993 Predominant
Columbia 95% (16%) 1995 Predominant (exclusive)
19% 1993 Exclusive
Dominican Republic 10% 1991 Exclusive
14% 1986 Exclusive
Ecuador 96% 1994 Predominant
Egypt 68% 1995 Exclusive
Ethiopia 78% 2000 Exclusive
Mali 12% 1996 Exclusive
8% 1987 Exclusive
Mexico 37.5% 1987 Exclusive
Niger 4% 1992 Exclusive
Nigeria 2% 1992 Exclusive
Pakistan 25% 1992 Exclusive
12% 1988 Exclusive
Poland 17% 1995 Exclusive
1.5% 1988 Exclusive
Saudi Arabia 55% 1991 Exclusive
Senegal 7% 1993 Exclusive
South Africa 10.4% 1998 Exclusive
Sweden 61% 1993 Exclusive
55% 1992 Exclusive
98% 1990 Predominant
Thailand 4% 1996 Exclusive
99% (0.2%) 1993 Predominant (exclusive)
90% 1987 Predominant
Zambia 23% 1996 Exclusive
13% 1992 Exclusive
Zimbabwe 38.9% 1999 Exclusive
17% 1994 Exclusive
12% 1988 Exclusive

Other issues

Lactation without pregnancy

Although not widely known in developed countries, women who have never been pregnant are able to lactate and therefore breastfeed as well. If their nipples are stimulated in a breastfeeding manner for a while (such as a breast pump or an actual baby suckling), eventually the breasts will begin to produce milk which can be used to feed a baby. For this reason, adoptive mothers, usually initially in conjuction with some form of supplementation, are able to breastfeed their infants. There is also anecdotal evidence of male lactation.

Circumcision

Some reports have suggested that the act of circumcision may have a negative effect on the feeding habits of the baby [14]. The topic of circumcision itself is hotly debated, however, and findings of its impact can often be reported with bias.

See also

References

Printed references:

  • Breastfeeding, Biocultural Perspectives; Editors Patricia Stuart-Macadam & Katherine A. Dettwyler.
  • La Lêche League (1995). The Breastfeeding Question and Answer Book.
  • Mercurialis, H. (1583). De Morbis Puerorum.
  • Minchin, M. (1985). Breastfeeding matters, Almo Press Publications, Australia. ISBN 0-86861-810-1
  • Moody, J., Britten, J. and Hogg, K. (1996). Breastfeeding your baby, National Childbirth Trust, UK. ISBN 0-72253-635-6
  • Royal College of Midwives (1991). Successful Breastfeeding: A Practical Guide for Midwives, Royal College of Midwives, London.
  • Stuart-Macadam, P. and Dettwyler, K. (1995). Breastfeeding: Biocultural Perspectives (Foundations of Human Behavior), Aldine de Gruyter. ISBN 0-20201-192-5

Website references:

External links

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