Sometimes we find that the reason for a consultation is weight stagnation in infants who had previously had adequate weight gain for their age.

When faced with these cases, it is important to make a thorough assessment of the situation, not only of breastfeeding but also of other reasons for this possible slow down of weight gain. It is also important to monitor changes in the infant’s behaviour. The mother’s sensations and perceptions can also provide us with valuable information.

Among the possible causes of weight stagnation are:

Child-related causes:

• Infant illnesses or infections, whether upper respiratory, gastroenteritis or urinary tract infections. The difficulty with UTIs is that their symptoms are latent, so a urine culture test is one of the tests to be performed in these cases.
• Sores, cold sores or inflammatory processes in the child’s mouth or larynx.
• Ankyloglossia (tongue-tie). Sometimes, when the baby has tongue-tie, during the first weeks the difficulty in expressing milk is compensated by the maternal milk let-down (ejection) reflex. When milk production becomes self-regulated, this reflex may not be as active, and therefore there may be difficulty in milk transfer.
• The baby might have dropped night feeds without the mother intentionally doing so

Maternal-related causes:

• The mother has started hormonal contraceptive treatment. The CDC advises against the use of combined hormonal contraceptives during breastfeeding, even at low doses. Although there is no published scientific literature on the subject, we have observed mothers who have also noticed a change in milk production when starting treatment with progestogens alone. As always, advice should be individualised by listening to the mother.
• Treatment with medications that cause a decrease in milk production (such as antihistamines, corticosteroids, etc.).
• The mother might have postpartum thyroiditis.
• The mother might have mastitis. During mastitis, there is usually a reduction in milk production. There is also difficulty in milk ejection if there is inflammation of the ductus or a reduction in its diameter due to bacterial biofilms. If there is severe inflammation of any area of the breast, apoptosis of the glandular tissue may occur.
• The mother is dehydrated or has severe gastroenteritis.
• Alcohol and tobacco abuse. Alcohol decreases oxytocin concentration, and tobacco decreases prolactin production. The combination of the two can lead to decreased milk production.
• Very restrictive maternal diets of less than 1800 KCal/day.
• The dropping of night feeds decided by the mother
• The mother is pregnant.
• Return to work

Most of the above situations are not usually included in the scientific literature, and if they are, it is very limited, and the methodology and results are not very robust. Despite this, these situations are frequently seen in healthcare practice.

References:

Walker, Marsha. Breastfeeding Management for the Clinician. Using Evidence. 4rth Edition. Burlington, MA: Jones & Bartlett Learning; 2017.

Lawrence, Ruth A.; Lawrence, Robert M. Breastfeeding. A guide for the medical profession. Seventh Edition. Missouri: Elsevier Mosby; 2017.

Temboury Molina, MC, García Jiménez, C, Ares Segura, S. Lactancia Materna. Madrid. Editorial Médica Panamericana. 2021.