Breastfeeding is a form of feeding that begins at birth with milk produced in the mother’s breast. The World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) point out that breastfeeding is a unique way of providing the ideal food for the correct growth and development of children.
WHO and UNICEF consider exclusive breastfeeding for the first six months of a newborn to be essential. And recommend that from that age and up to two years of age, in addition to breastfeeding, babies should be offered other foods appropriate to their age. The American Academy of Pediatrics recommends maintaining breastfeeding for at least the first year.
According to WHO and UNICEF, from the first two years breastfeeding has to be maintained until the child or mother decides, without any time limit. It is not known what is the ideal duration of breastfeeding in the human species. The references on the terms and characteristics of breastfeeding are understood from the cultural context of breastfeeding mothers, in such a way that breastfeeding periods can be extended as much as the variability of existing cultures in the world. We can refer to cases in which it is considered only for babies a few weeks or months old, as well as cases in which breastfeeding has been maintained for several years.
Some published anthropological studies conclude that the natural breastfeeding interval in humans is between two and a half and seven years of age.
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Breast milk
Human breast milk is the natural food produced by the mother to feed the newborn. It is recommended as an exclusive food for the infant up to six months of age and with complementary feeding up to two years of age, since it contains most of the nutrients necessary for its correct growth and development. It also contains immunoglobulins and other substances that protect the baby against infections and contributes to strengthen the bond between mother and child, promoting proper psychomotor development.
Brief history
Breastfeeding is a biological behaviour subject to modification by social, economic and cultural influences, which has remained a standar for human babies from the origins of humanity until the end of the nineteenth century, whether it is the mother’s own milk or another mother’s milk, in exchange or not for some kind of compensation.
At the beginning of the 20th century, what has been considered to be the largest large-scale experiment in an animal species begins: the human species has its initial form of feeding changed and children are fed modified milk from a different species.
The frequency and duration of breastfeeding declined rapidly throughout the twentieth century. In 1955, the Protein Advisory Group (GAP) was created at the United Nations to help WHO provide technical advice to UNICEF and FAO in their programmes of nutritional assistance and advice on the safety and adequacy of human consumption of new protein foods. In the 1970s, the GAP issued reports warning of concern about the problem of child malnutrition resulting from the abandonment of breastfeeding and inviting the industry to change its practices of advertising products for infant feeding.
In 1979 WHO/Unicef organizes an international meeting on infant and young child feeding. The meeting resulted in a resolution to draft the International Code of Marketing of Breastmilk Substitutes. IBFAN was also founded to ensure the development of the Code. At the same time, the scientific community’s interest in breastfeeding is re-emerging and a great deal of research is being done on it. Evidence is accumulating on the superiority of human milk for infant and young child feeding. Other researchers focus their efforts on the study of the conditions of breastfeeding and the factors influencing the choice of breastfeeding and its duration. Social movements, breastfeeding support groups and scientific evidence that the abandonment of breastfeeding is a priority public health issue in all countries of the world prompted international and national institutions, led by WHO, to launch different initiatives.
In 1981, the 34th World Health Assembly WHA 34.22 was convened, which approved the International Code of Marketing of Breastmilk Substitutes, an ethical commitment to be adopted by different governments. The slowness of governments to translate the Code’s recommendations into law led WHO and UNICEF to promote international meetings dedicated to supporting breastfeeding.
In 1989, WHO/Unicef issued a communiqué to governments: “Protection, promotion and support of breastfeeding. The role of maternity services” In the same year the United Nations adopted the Convention on the Rights of the Child. Article 24 (e) made express reference to the need to ensure that all sectors of society, and in particular parents and children, are aware of the benefits of breastfeeding and receive support for the application of this knowledge.
At a former orphanage in Florence (Ospedalle degli Innocenti, 1990), a World Summit on “Breastfeeding in the 1990s: A Global Initiative” was held, attended by representatives of 30 countries supporting the Convention on the Rights of the Child and signed a declaration of commitment: Innocenti Declaration which will serve as a reference for the promotion of breastfeeding for many years to come, to be revised in 2005.
A direct consequence of this Declaration was the creation, in 1991, on the one hand, of the World Alliance of Breastfeeding Action (WABA), an international network of people and organizations that work in collaboration with WHO/Unicef with the mission of annually organizing the World Breastfeeding Week, and on the other hand, the Initiative for the Humanization of Birth Attendance and Breastfeeding (IHAN) -initially called the Child-Friendly Hospital Initiative-, which seeks to evaluate the quality of care for mothers and children in hospitals and maternity hospitals.
In 1992, the International Conference on Nutrition, convened by FAO and WHO in Rome, accepted the goals for the year 2000 of the World Summit for Children, highlighting the promotion of breastfeeding among the 8 most important themes of world nutrition. In 1994, the Summit on Promotion and Development recommended breastfeeding as a tool for improving maternal health and spacing pregnancies. The World Summit on Women and Development (Beijing, 1995) supported the need to make it easier for working women to breastfeed. In 1999, the International Conference of the ILO revised the Maternity Protection Convention which consolidated the right to paid maternity leave for all working women and the right to paid intervals for breastfeeding during the working day.
The WHO Assembly of 1994, in resolution 47.5, set the optimal duration of exclusive breastfeeding at 6 months and drew attention to the error of distributing breastmilk substitutes in emergency situations and proposed collecting data on the growth of breastfed infants that could be used to develop a new growth pattern.
In order for governments to become more involved in breastfeeding and provide financial resources, the Global Strategy for Infant and Young Child Feeding (EMALNP) was approved by consensus of the 55th WHO Assembly WHA 55.25, in May 2002 and by the UNICEF Executive Board a few months later. The strategy sets out lines of action to be followed by member countries, based on scientific evidence. Most of the recommendations are aimed at improving breastfeeding rates. It is recognized that breastfeeding is partly a learned behaviour and that mothers need to be offered places where they can learn, such as breastfeeding support groups, protected from commercial advertising.
The Strategic Plan for the Protection, Promotion and Support of Breastfeeding was presented in Dublin in 2004 by the European Commission’s Directorate-General for Health and Consumer Protection. This document recognises the recommendations of EMALNP and adapts them to the reality of Europe.
In 2006 the European Union publishes the Standard Recommendations for Infant and Young Child Feeding in the European Union which is a comprehensive guide to infant and young child feeding from gestation to three years of age. It contains special sections for premature babies, situations that contraindicate breastfeeding, risks of not breastfeeding and recommendations for the appropriate and safe use of substitutes when the mother so chooses.
In coordination with institutional bodies, researchers have studied the social impact of breastfeeding throughout history, developing strategies to encourage increased rates of breastfeeding in different countries.
Artificial Breastfeeding
Breastfeeding is a way for the infant to feed if the mother is unable or chooses not to. The so-called artificial lactation, applied to the feeding of calves and other farm animals, was invented to give way to the surplus production of cow and goat milk, which was preserved in powder and later rehydrated for use. A few years later, at the initiative of Henri Nestlé’s company, its use in humans began. It reached its maximum popularity in the 1960s in Argentina. Subsequently, its use decreased due to the disadvantages of this type of feeding with respect to breastfeeding.
This means that there are no clocks and the child decides when to feed. It is common for a child, the younger he or she is, to demand more often, especially at night. The myth that a child should eat every three hours for ten minutes of both breasts is not a generality, most children do not drink this way.
In addition to infant formula, there are other types of special milks for children with food allergies, such as in cases where cow’s milk proteins are not tolerated. There are cases of intolerance to human milk proteins, such as galactosemia, a metabolic disease caused by an enzyme deficiency and manifests itself in the inability to use simple sugar galactose.
It is estimated that approximately one hundred substances that exist in breast milk have not yet been imitated by artificial compounds.
Breastfeeding status
The abandonment of breastfeeding as a routine form of infant feeding can translate into a problem with important personal, social and health implications. Its relevance has been highlighted by the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) in different statements.
An added difficulty is that there are no comparative registers or indicators on breastfeeding, so it is difficult to establish the real magnitude of the problem. In Spain, a study was carried out by the Breastfeeding Committee of the Spanish Paediatrics Association in 1997, which uniformly collects data from several Spanish provinces. This study obtained an average duration of breastfeeding of 3.2 months. The other source with territorially represented data corresponds to the 2006 National Health Survey with exclusive breastfeeding prevalence at the beginning of 68.4%, 52.48% at three months of age and 24.27% at six months. There are also differences in breastfeeding rates among the different European regions.
In order to obtain data on the onset and prevalence of breastfeeding in recent years in Spain, epidemiological studies carried out at regional or even local level must be used. According to 2005 data from Catalonia (Spain), the prevalence of breastfeeding at the beginning stands at 81.1%, although of this only 66.8% is exclusive. In the third month, the rate of total lactation stands at 61.9%, at six months at 31.3% and at one year at 11.5%. However, with data from 1989, total breastfeeding at the beginning was 72 %, at three months 39.2 % and at six months 6.3 %, there are no data on annual prevalence at that date. There are significant differences in breastfeeding rates comparing different Spanish autonomies, but the trend towards a gradual increase in breastfeeding initiation and prevalence rates is common.
In Latin America, breastfeeding among indigenous peoples has been encouraged and valued by culture. And although from this perspective it is agreed that there are no systematic studies, the available data do show that it is a practice for which some indicators are offered, as in the case of Mexico.
The 2012 National Health and Nutrition Survey conducted by the National Institute of Public Health and the Ministry of Health in Mexico found that the duration of breastfeeding in Mexico is about 10 months; a stable figure in the three nutrition and health surveys of 1999, 2006 and 2012 (9.7, 10.4 and 10.2 months, respectively). The rest of the breastfeeding indicators indicate a clear deterioration of breastfeeding. The percentage of exclusive breastfeeding in children under six months of age fell between 2006 and 2012, from 22.3% to 14.5%, and was dramatic in rural areas, where it fell by half (36.9% to 18.5%).
Similarly, continuous breastfeeding at one and two years decreased. An additional 5% of children under six months of age consume formula and the percentage of children who in addition to breastmilk consume unnecessary water increased. This is negative because it inhibits milk production and significantly increases the risk of gastrointestinal diseases. Mothers who never breastfed mention as reasons ignorance or little support before and around childbirth, to initiate and establish breastfeeding. In contrast, complementary feeding in Mexico has improved in quality and frequency. The percentage of children who consume iron-rich foods in a timely manner, the introduction of other foods and the diversity of the diet of children in their second semester of life show positive changes. The number of children who consume iron-rich foods in the second semester of life has increased.
Definitions for different types of feeding
In 1991, WHO coined precise definitions of infant feeding types. These definitions should be used in lactation studies so that results can be compared between studies.
- Exclusive breastfeeding: breastfeeding, including expressed or wet nurse’s milk. It allows the infant to receive only drops or syrups (vitamins, medicines or minerals) in addition to milk.
- Predominant breastfeeding: Breastfeeding, including expressed or wet milk as the primary food source, allows the infant to receive liquids (water, sweetened water, infusions, juices), ritual beverages, drops, or syrups (vitamins, medicines, or minerals).
- Complete breastfeeding: includes exclusive breastfeeding and predominant breastfeeding.
- Complementary feeding: breast milk and solid or liquid foods. Allows any food or liquid including non-human milk.
- Breastfeeding: feeding by mother’s milk.
- Bottle feeding: any liquid or semi-solid food taken with a bottle and teat. Allows any food or liquid including human and non-human milk.
However, in the scientific literature it is possible to find other terms as well:
- Multiple breast-feeding: Breastfeeding by mother’s milk to two or more children of the same age.
- Deferred lactation: lactation for expressed breast milk.
- Direct breastfeeding: when the baby is fed by drinking milk directly from the breast.
- Tandem Breastfeeding: Breastfeeding by the mother’s own milk to two or more children of different ages.
- Induced lactation: lactation by milk from a mother other than her own without a previous pregnancy in the mother.
- Mercenary lactation: lactation for milk from a mother other than one’s own in exchange for some form of remuneration.
- Mixed lactation: popular way of referring to complementary lactation (human milk+non-human milk). WHO recommends that this term not be used in scientific research.
- Breastfeeding in solidarity: Breastfeeding for mother’s milk other than one’s own without remuneration.
- Relactation: exclusive breastfeeding for the mother’s own milk after a period of complementary feeding or suspension of breastfeeding.
Advantages of breastfeeding
Infection prevention
An infection that is prevented or reduced in frequency by breastfeeding is gastroenteritis, the most important, at least in developing countries. This disease is very rare in infants who feed only on human milk. Necrotizing enterocolitis, on the other hand, occurs less frequently in breastfed infants than in those receiving cow’s milk. In addition, breast milk provides protection against cholera. Many studies indicate that there is a lower incidence of respiratory infection in breastfed children. Another obvious reason for increased incidence of gastroenteritis due to formula feeding is contamination of bottles and nipples as well as poor storage. Infant botulism is virtually limited to infants fed industrialized milk. The lower risk of sudden infant death in breastfed infants is not fully explained.
According to Spanish research, breast milk contains more than 700 types of bacteria. They have used a technique based on massive DNA sequencing to identify the set of bacteria called a microbiome.
Prevention of food sensitivities
The presence of dietary allergens in breast milk, such as egg proteins, gluten (contained in wheat, barley, rye, oats, and all their hybrids), cow’s milk, and peanut milk, has been widely demonstrated. In general, concentrations are related to the amount of food ingested by the mother. Allergens pass rapidly into breast milk within minutes of ingestion and may remain for several hours.
It has been suggested that this dietary allergen exposure through lactation induces tolerance in the infant, although it has not been established how and when to expose infants to potential dietary allergens with the aim of inducing tolerance or preventing the development of further sensitization.
In the case of gluten, it has been shown that neither early exposure to gluten nor the duration of breastfeeding prevents the risk of developing celiac disease, although delayed introduction of gluten is associated with delayed onset of the disease. This contradicts recommendations issued in 2008 by the European Society for Paediatric Gastroenterology (ESPGHAN) for families of children at risk of developing celiac disease, which consisted of gradually introducing small amounts of gluten into the diet during the first 4-7 months of life, while maintaining breastfeeding.Genetic risk (presence of haplotypes HLA-DQ2, HLA-DQ8, or one of their alleles) is an important predictor of the possibility of developing celiac disease.
Contraindications
In scientific literature, a distinction is often made between true contraindications and false contraindications or myths:
True contraindications
- AIDS: in developed countries it is considered a true contraindication. In other parts of the world, infant mortality from malnutrition and infectious diseases, associated with artificial breastfeeding, is considered to be higher than the risk of AIDS transmission through breastfeeding. In other parts of the world, infant mortality from malnutrition and infectious diseases, associated with artificial breastfeeding, is considered to be higher than the risk of AIDS transmission through breastfeeding.
- Herpes simplex — in newborns less than 15 days old, can cause a life-threatening infection. During the first month the presence of herpes simplex lesions in a nipple contraindicates the lactation of that side until it heals. People with cold sores should not kiss babies either.
- Galactosemia in the baby: severe congenital disease due to a deficit of the enzyme galactose-l-phosphate uridyl transferase in the liver. Children who have galactosemia should drink milk that is completely lactose-free.
- Phenylketonuria in the baby: is due to a deficit of phenylamine hydroxylase; if not treated early, the child develops a progressive neurological condition that leads to mental retardation. What is indicated in these cases, in terms of nutrition, is to combine breast milk with a special milk without phenylalanine, controlling the levels of this amino acid in the blood.
False Contraindications
- Hair loss: it is common a great loss of hair after childbirth that has sometimes been related to breastfeeding. It is actually a normal and benign phenomenon called telogen effluvium that resolves spontaneously between 6 and 12 months postpartum, without leaving residual alopecia.
- X-rays: The x-rays do not remain on the irradiated object, are not transmitted through breast milk, and do not alter its properties. There is also no risk to the infant if the mother undergoes ultrasound, CT scan, or MRI. Iodine contrasts are barely passed into breast milk and are not absorbed orally. Barium contrasts cannot pass into milk. Gadonpentate and gadoteridol are absorbed orally, have few side effects, and both are commonly used in newborns. In all these cases, the mother can breastfeed immediately after an X-ray and “irradiated” milk does not need to be discarded.
- Scans: depending on the type of isotope used and the dose administered, breastfeeding may continue normally, although in some cases it may be advisable to stop breastfeeding and discard the milk for a few hours or even days.
- Dental fillings: the mercury amalgam used in fillings is not toxic. The local anesthesia used in dental procedures does not pass into milk. There are analgesics, anti-inflammatories or antibiotics suitable for these cases that are compatible with breastfeeding.
- Myopia: the ophthalmology treaties do not mention any relationship between lactation and the evolution of myopia. The origin of this myth is unknown.
- Caries in the mother: there is a myth that lactation produces caries in the mother by decalcification of the teeth. Tooth enamel has no blood supply and cannot be decalcified due to metabolic changes affecting the rest of the skeleton.
- Childhood tooth decay: The relationship between breastfeeding and tooth decay is not clear because it is a multicausal disease. The conclusion of multiple studies on the subject can be summarized by saying that the prevention of infant caries involves kissing the baby (triggers immunity against streptococcus mutans from maternal saliva), breastfeeding, avoiding bottles, juices, infusions, honey or sugar (especially at night), avoiding sweets and treats, starting dental hygiene as soon as possible and administering fluoride after six months if appropriate.
- Physical exercise: physical exercise during lactation can improve the mother’s well-being and fitness without affecting the amount or composition of milk or harming the infant.
- UVA rays: UVA rays are carcinogenic but the risk is only for the person who is exposed to them, they do not affect lactation, milk or baby. Breastfeeding is possible immediately after the mother applies them.
- New pregnancy: no complication of pregnancy caused by breastfeeding has been described. Most children wean spontaneously during pregnancy, probably due to decreased milk production. Those who are not weaned can continue to breastfeed with their sibling, which is called tandem breastfeeding.
Smoking in breastfeeding
Smoking during pregnancy causes more damage than smoking during breastfeeding and increases the risk of sudden death. Smoking during lactation is also contraindicated. Passive exposure of children to tobacco smoke is associated with an increased risk of lower respiratory tract disease, otitis media, asthma, and sudden infant death syndrome. According to some studies, maternal smoking is associated with shorter duration of breastfeeding because tobacco reduces milk volume, although other studies maintain that women who smoke are less likely to breastfeed their infants than nonsmokers because of less motivation and not a physiological effect of tobacco use on their milk supply. Other studies show that women who smoke produce less quality and less quantity of breast milk.
Maternal smoking increases the risk of airway disease in breastfed infants for 0 to 6 months but not necessarily when the infant was breastfed for more than 6 months. One study indicated a long-term protective effect of breastfeeding on the risk of respiratory tract infection during the first year of life. The results suggest that the protective effect is stronger in children exposed to environmental tobacco smoke, so that artificial lactation is assumed to potentiate the harmful effects of smoking, increasing respiratory infections hospital admissions and the risk of developing asthma.
Drugs during breastfeeding
The vast majority of medications can be used during breastfeeding. Although many of the leaflets identify pregnancy and breastfeeding as the same period, the truth is that they are two completely different moments and not comparable to each other in these effects. The use of medications during breastfeeding should be known by a physician. Not all drugs pass into milk and in general, in practically all circumstances alternatives can be offered if the chosen drug carries some kind of risk. Some drugs are compatible with breastfeeding and others are not. Breastfeeding should be temporarily interrupted during the use of medications that may affect the baby and may be resumed later. Even in cases where the mother supposes that she has run out of milk, it is possible to induce her new appearance. With a few drugs, breastfeeding cannot be resumed in any way, as in the case of prolonged treatments or anti-cancer treatments with radioactive substances such as chemotherapy. It also depends on the age of the infant. In most cases, there is no danger of resuming breastfeeding.
In 2002 a group of medical professionals from the Marina Alta hospital in Alicante conceived and implemented the e-breastfeeding project, a large and updated database on the compatibility of breastfeeding with medicines, plants, toxins and diseases which has become a reference point for midwives and paediatricians in Spain.
Undiagnosed celiac disease
Undiagnosed celiac disease can affect breastfeeding and cause it to be significantly reduced in duration. The adoption of the gluten-free diet has been shown to increase the lactation period to match the average for healthy women.
Celiac disease is an autoimmune disease caused by the consumption of gluten, which can affect any organ. It usually occurs without any digestive symptoms and most cases are neither recognized nor diagnosed. Reproductive disorders are often the only indication of celiac disease, such as irregular menstruation, infertility or reduced fertility, miscarriage, pregnancy complications, intrauterine growth restriction, fetal death, premature delivery, and short duration of lactation.
Ten Steps to Effective Breastfeeding
In 1991, WHO, together with Unicef and the Pan American Health Organization, launched the Child-Friendly Hospital Initiative (IHAN), with the purpose of implementing practices that protect, promote and support breastfeeding. This initiative includes the ten steps to effective breastfeeding. The steps are summarized as follows:
- STEP 1. Has a written breastfeeding policy that routinely brings to the attention of maternity staff
- STEP 2. Train health personnel in the skills necessary to implement this policy.
- STEP 3. Inform all pregnant women about the benefits and management of breastfeeding.
- STEP 4. Help mothers initiate breastfeeding within half an hour after delivery.
- STEP 5. Show mothers how to breastfeed, and how to maintain breastfeeding even if their babies are separated.
- STEP 6. Do not give the newborn food or liquid other than breast milk, unless medically indicated.
- STEP 7. Practice joint housing. Allow mothers and their newborns to stay together 24 hours a day.
- STEP 8. Encourage breastfeeding on demand.
- STEP 9. Do not give bottles, pacifiers or distraction pacifiers to breast-feeding babies.
- STEP 10. Form breastfeeding support groups, refer mothers to these groups at discharge from hospital or clinic.