4.3 Causes of inadequate infant growth
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![]() Key Points - Case Study DSally is 29 years old and presents to see you two and a half weeks postpartum with her first baby. Emily was born at T+7 days and weighed 4060 grams. Sally had a normal delivery but had a postpartum haemorrhage and a retained placenta that required a general anaesthetic and manual removal. They were discharged on day three fully breastfeeding, with Emily weighing 3770 grams and Sally's Hb 92 g/L. Sally has no other significant medical or surgical history, is well educated and has a supportive partner. Emily is a "good" baby: she is sleeping at least six hours at night and seems content. What questions would you ask Sally, and what additional information would you gather to assess whether breastfeeding was progressing normally?
Sally is confident with her breastfeeding and her breasts and nipples are fine. Her breasts feel a little fuller early in the morning, but she has not had problems with engorgement like some of her friends. Emily is feeding approximately six times a day and feeds for 15-20 minutes before falling asleep. She is having four wet nappies a day – two of which are damp. She is having a bowel motion every three days or so. Emily weighs 3800 grams. On examination, she is not dehydrated. You are concerned that Emily is not getting enough breast milk.
What may cause inadequate growth in breastfed infants such as Emily?
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What may cause inadequate growth in breastfed infants such as Emily?
Reduced milk intake due to feeding patterns or routines
- Frequency
- As mentioned earlier, most infants require at least eight breastfeeds a day in the early months of life (i.e. at least every three hours). However, breastfeeds are not usually spaced evenly throughout the day. At times the infant may want to feed every 3060 minutes (cluster feeds) while they may go for a longer stretch during the night. Feeding frequency is positively correlated with milk volume in the early weeks1. Additionally, because of the differences in maternal storage capacities and infant feeding cues, stipulating a specific number of breastfeeds at equal intervals throughout the day limits the volume of milk the infant receives and reduces breast stimulation and drainage necessary for further milk production. Night-time feeds are also important for ongoing breastfeeding, especially in the early weeks and months.
- Length of feeds
- In the first few weeks postpartum, most infants will take between 20 and 40 minutes to feed; however, the length of effective sucking will vary between infants and between feeds by the same infant. However, limiting the time at the breast, or removing the infant from the breast after a specified time, may not allow the infant to receive as much milk as he or she needs, especially if the milk-ejection reflex is slow. Conversely, infants who spend a long time at the breast (>50 minutes routinely) may not be feeding effectively for some or all of that time, and the breastfeeds may need to be assessed by a trained observer.
- One breast or two
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Fat concentration of breast milk is correlated with the degree of breast fullness – with the fat concentration increasing as the breast is drained. Concern has been expressed that infants feeding from both breasts at each feed when their mothers' milk supply is large would receive a low-fat, high-volume feed resulting in symptoms of lactose intolerance and large, or rarely low weight gain2. Conversely, mothers may initially be encouraged to feed from only one breast at each feed while their breasts are very full or engorged, or to ensure their infant receives the higher fat milk when the breast is drained. This advice can be interpreted as only ever feeding from one breast at each feed. For many infants, this routine will not provide sufficient milk volume for adequate growth.
The ideal situation is to allow the infant to feed from one breast for as long as he or she is feeding effectively, and then offer the second breast. Most infants (57%) will take one breast at some feeds and two breasts at others, while some infants will only ever use one breast at each feed (30%) and others will always use two breasts (13%)3. Most infants with signs and symptoms of lactose overload respond well when allowed to determine whether they feed from one breast or two at a feed. Lactose-free formula is not necessary nor appropriate management.
- Use of breast/breast milk substitutes
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Dummy or pacifier use has been associated with reduced breastfeeding duration (4,5). Dummies are thought to reduce the desire of the infant to feed at the breast, especially if used to quieten the infant rather than feeding him or her, or alter the infant's sucking pattern. However, it is difficult to determine whether dummies initiate breastfeeding problems or are used because of them.
Complementary feeds also reduce the infant's desire to feed at the breast. If the complement is infant formula, the infant's weight may not be affected, but milk supply will invariable decrease unless measures are instituted to increase milk production.
Feeding routines that reduce breast drainage not only affect infant growth, but also adversely affect ongoing milk supply.
Low milk supply
- Hormonal reasons
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- Retained products of conception. A rapid decrease in progesterone levels is essential for the initiation of lactation. When progesterone levels fail to fall to pre-pregnancy levels due to retained products of conception, milk production is often slow to begin and does not reach normal levels. Removal of the retained products usually results in a rapid increase in milk volume (6,7).
- Sheehan's syndrome and postpartum haemorrhage. Sheehan's syndrome, due to ischaemic necrosis of the pituitary gland following hypotension related to severe postpartum haemorrhage, may present initially with failure to lactate. Some authors report women experiencing a delay in the initiation of lactation, or low milk supply following episodes of postpartum hypotension (usually due to postpartum haemorrhage), although the remainder of the pituitary function is intact (8,9). Another study showed a relationship between postpartum anaemia and apparent insufficient milk, leading to early weaning10. Although the study did not report the reasons for anaemia, excessive peripartum blood loss may have contributed.
- Thyroid disorders. As thyroxine is also required for ongoing milk production, women with hypothyroidism are at risk of having a low milk supply. Adequate treatment with thyroxine allows breastfeeding to commence and continue normally11. Postpartum thyroiditis often presents initially with hyperthyroidism, with many women becoming hypothyroid with time12.
- Other hormonal disorders. There is some evidence that women with polycystic ovaries (13,14) and theca-lutean cysts (15,16) are more likely to have difficulty establishing their milk supply or produce a low milk volume. In rare instances, an isolated prolactin deficiency leads to alactogenesis (17,18,19).
- Smoking
- Women who smoke are less likely to initiate lactation and breastfeed for a shorter length of time. However, it is uncertain whether this effect is due to a lack of maternal motivation or a direct effect of nicotine or other substance on milk production (20,21,22).
- Obesity
- As described previously, women who are overweight or obese have difficulty establishing breastfeeding are less likely to continue to breastfeed.
- Medications
- Some medications such as the oral contraceptive pill23, pseudoephedrine24 and herbal preparations such as sage tea11 are known to inhibit milk production.
- Anatomical problems
- Some women lack sufficient mammary tissue to produce enough milk for their infant25. These women are more likely to have asymmetric underdeveloped breasts that are more widely spaced than normal (>4 cms). In extreme cases, the breasts sit on a small base with severe breast constriction and large nipple-areola complexes (tubular breasts)26. Lack of breast development during pregnancy and lack of postpartum breast fullness are often noted (26,27).
- Breast surgery
- Disturbance of ductal structures, reduction in the amount of glandular tissue and the severing of the afferent arm of the milk-ejection reflex (usually the lateral cutaneous branch of the 4th intercostal nerve) as a consequence of breast surgery can all impact on the mother's capacity to produce milk27. Breast reduction surgery nearly always results in reduced milk volume. Periareolar incisions, although cosmetically desirable, are more likely to interfere with the major lactiferous ducts and the milk-ejection reflex and have been associated with a reduction in nipple sensitivity (11,27).
Difficulty transferring milk
- Poor positioning and attachment
- Breast drainage is facilitated by optimal positioning and attachment of the infant at the breast. Case E describes the assessment of effective positioning and attachment.
- Efficacy of the milk-ejection reflex
- Contraction of the myoepithelial cells around the lactiferous ducts (the milk-ejection reflex), either stimulated by the infant or by expressing, is essential for the removal of milk from the breasts. Stress, pain or other factors may inhibit this reflex and must be considered when an infant is not gaining weight. While most mothers will be aware of this reflex working, it is often less noticeable for women with a low milk supply. Watching for changes in the infant's sucking pattern (from suck-suck-suck-swallow to suck-swallow, suck-swallow) may be a more reliable sign that milk is flowing.
- Sucking problems
- Some infants, even though they are positioned and attached to the breast well, have a poor or ineffective suck. Contributing factors include hyper or hypotonia, thumb-sucking in-utero, prematurity or illness. However, other infants may have tonic bites or are not able to coordinate tongue movements or maintain sufficient negative pressure to extract milk. These infants tend to slip off the breast easily and may "click" during the feed every time suction is broken. Their mothers often have damaged nipples.
- Tongue-tie (ankyloglossia)
- Further information about tongue-tie and its effect on breastfeeding is found in Case E.
Increased energy expenditure
- Other medical conditions
- Congenital heart disease, urinary tract infections and other medical conditions may initially present with low weight gain and failure to thrive. As well as having an increased energy expenditure, the infant may not be robust enough to adequately stimulate the breast, resulting in a secondary low supply problem.
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![]() Case Study ActivityThink about what your response would be to the scenario presented, write it into the exercise, then submit it and read the suggestions given. |
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Notes
- # Hill PD et al. (2005) Primary and secondary mediators' influence on milk output in lactating mothers of preterm and term infants
- # Woolridge MW et al. (1988) Colic, "overfeeding", and symptoms of lactose malabsorption in the breast-fed baby: a possible artifact of feed management?
- # Kent JC et al. (2006) Volume and frequency of breastfeedings and fat content of breast milk throughout the day
- # Howard CR et al. (2003) Randomized clinical trial of pacifier use and bottle-feeding or cupfeeding and their effect on breastfeeding
- # Kramer MS et al. (2001) Pacifier use, early weaning, and cry/fuss behavior: a randomized controlled trial
- # Anderson AM (2001) Disruption of lactogenesis by retained placental fragments
- # Neifert MR et al. (1981) Failure of lactogenesis associated with placental retention
- # Willis C et al. (1995) Infant insufficient milk syndrome associated with maternal postpartum hemorrhage
- # Livingstone V (2006) Failure to thrive while breastfeeding
- # Henly SJ et al. (1995) Anemia and insufficient milk in first-time mothers
- # Lawrence RA et al. (2005) Breastfeeding: a guide for the medical profession
- # de Swiet M (1995) Medical disorders in obstetric practice
- # Vanky E et al. (2008) Breastfeeding in polycystic ovary syndrome
- # Marasco L et al. (2000, May) Polycystic ovary syndrome: a connection to insufficient milk supply?
- # Betzold CM et al. (2004) Delayed lactogenesis II: a comparison of four cases
- # Hoover KL et al. (2002) Delayed lactogenesis II secondary to gestational ovarian theca lutein cysts in two normal singleton pregnancies
- # Saito T et al. (2007) A case of prolactin deficiency with familial puerperal alactogenesis accompanying impaired ACTH secretion
- # Douchi T et al. (2001) A woman with isolated prolactin deficiency
- # Kauppila A (1997) Isolated prolactin deficiency
- # Donath SM et al. (2004) The relationship between maternal smoking and breastfeeding duration after adjustment for maternal infant feeding intention
- # Giglia R et al. (2006) Maternal cigarette smoking and breastfeeding duration.
- # McAfee G ( 2007) Drugs of abuse and breastfeeding.
- # Hale TW (2007) Medications that alter milk production
- # Aljazaf K (2003) Pseudoephidrine: effects on milk production in women and estimation of infant exposure via breastmilk
- # Neifert MR et al. (1985) Lactation failure due to insufficient glandular development of the breast
- # Huggins K et al. (2000) Markers of Lactation Insufficiency: A study of 34 mothers
- # Neifert MR et al. (1990) The influence of breast surgery, breast appearance, and pregnancy-induced breast changes on lactation sufficiency as measured by infant weight gain