Poor Weight Gain Assessment For Infants

Many parents struggle with a baby who is not gaining adequate weight. The causes can be numerous, ranging from significant medical issues through to underlying breastfeeding (or feeding) problems. It is important that breastfed infants are plotted on the WHO infant growth charts, to really determine if a baby is struggling to gain weight. Other charts, such as the CDC ones, are designed for formula fed babies.

Our doctors are in an excellent position to evaluate causes of poor infant weight gain. Being GPs, we are skilled in managing both babies AND mothers; and working in the field of Breastfeeding Medicine, we can really tie it all together. We can assess for potential medical causes, order any tests that may be required, address any feeding issues as well as refer to a Paediatrician when appropriate.

Let us worry about the numbers on the scales, while you can just get on with being a parent.

Medical Conditions in Infants

Cows Milk Protein Allergy and Intolerance (CMPA/I)

Allergy to cow’s milk protein seems to be on the rise, although it is also often blamed for causing a baby to be unsettled despite little evidence that cows milk protein allergy (CMPA) causes this. The diagnosis is not to be taken lightly, so a thorough assessment needs to take place. Rarely, babies or children will develop a true IgE-mediated allergic reaction to cow’s milk protein and present with quick-onset hives, lip/tongue swelling, wheeze, diarrhoea and anaphylaxis. The more common presentation is non-IgE-mediated allergy, where symptoms occur 2-7 days after ingestion of the protein. This allergy causes a colitis (inflammation of the bowel) and is more commonly referred to as cow’s milk protein intolerance (CMPI). Babies who have this allergy can present with blood in their stool, diarrhoea, failure to thrive and/or severe reflux. The treatment is total exclusion of all dairy products. If the baby is breast fed, then mum has to exclude all dairy from her diet. If the baby is formula-fed, then a special formula needs to be prescribed. Unfortunately, a percentage of babies with CMPI will also be allergic to soy. A dairy and soy exclusion diet is very challenging and you will need help to navigate this path. Luckily, most babies will outgrow their allergy to cow’s milk at some stage.



Many parents are worried their baby has reflux. This condition has been over-diagnosed in recent times, often being blamed as the cause for an unsettled baby, with many babies being prescribed medication to suppress acid secretion (PPIs).

Firstly, all babies have “reflux”. Babies have a very weak lower-oesophageal sphincter which means it is easy for their stomach contents to come back up their oesophagus, into their mouth, and commonly onto the shoulder of their parent. Some babies seem to do this significantly more than others, but as long as they are gaining weight, there is no need for concern.

The good news is, that the stomach contents in babies under 4 months of age is close to pH neutral for 2 hours after a feed. This means their stomach contents are not acidic and are not causing any damage to their oesophagus. It also explains why the recent research proves that PPIs (medications prescribed to reduce acid in the stomach) are no better than placebo for babies under 4 months of age where reflux has been blamed for their unsettled behaviour.

Unfortunately, PPIs (ie Losec, Nexium) are not without potential harm and should only be used in those proven to have GORD (Gastro-oesophageal Reflux Disease). This is where there is proven damage to the oesophagus. Babies that have this condition do not gain weight, they might vomit blood, they might aspirate, and they will be unsettled. These babies need referral to a paediatric gastroenterologist for an endoscopic assessment. This is a very, very small subset of unsettled babies.


Information for Parents with Older Babies

Starting Solids

Starting your baby on solids is an exciting but confusing time. Most parents have a lot of questions about starting solids.

When should I start my baby on solids?

There has been a lot of conflicting advice about the best time to start your baby on solids. Look for signs that your baby is ready. These include:

  • Good head and neck control
  • Shows an interest in food e.g. reaches out for your food when you are eating
  • Opens his or her mouth when offered a spoon

This usually occurs around 6 months. The advice from ASCIA (Australian Society of Clinical immunology and Allergy) recommends that all infants are given common food allergens (i.e. peanut, egg, dairy and wheat) in the first 12 months of life. WHO guidelines recommend excusive breastfeeding for the first 6 months of a baby’s life and continued breastfeeding during introduction of solids.

Why does my baby need solids?

From around 6 months a baby’s iron stores gained during your pregnancy have reduced. Breastmilk and formula do provide some iron but not enough to maintain iron levels by themselves. Learning to eat is also a sensory experience for your baby and assists in language development.

How to start solids

Embrace the mess and be patient! There is a lot of different advice about starting solids. We recommend following your baby’s cues – it is your role to offer a wide variety of food, and your baby may or may not choose to eat it. It is best to first offer solids after a milk feed. You may to choose to offer mashed/pureed food first of all, or soft pieces of food to try. Offer a wide variety of foods including vegetables, fruit, meat, dairy and eggs. As the months pass, offer different textures. Expect your baby to be sharing in family meals by 12 months. Cow’s milk as a whole drink is not recommend prior to 12 months due to the risk of iron deficiency, although you can add to cereal or use in baking.

There are some foods that your baby may not enjoy straight away. Don’t lose heart and try again another time. You may also wish to offer your baby cooled boiled water in a sippy cup. You will need to supervise your child eating at all times.

Things to Try

Offer a variety of foods such as:

  • Grains – bread, pasta, rice, oats
  • Dairy – yoghurt, cheese, custard
  • Meat and alternatives– beef, lamb, poultry, seafood, lentils, chickpeas, eggs (well cooked). You can offer strips of meat, lamb chops, chicken drumsticks or pureed/mashed.
  • Fruits and vegetables – roasted vegetable wedges, steamed vegetables, soft fruits

Resources we use

Dr Andrew and Dr Smith both have young children and found the following resources useful when starting solids for their babies

  • One Handed Cooks – recipe book and blog – includes ideas for family meals
  • Baby Mealtimes on Instagram (page by dietitian in Perth)
  • Ellyn Satter 


Food Protein-Induced Enterocolitis Syndrome (FPIES)

FPIES is a non-IgE-mediated allergic reaction to a food protein. It is more commonly seen as parents start to introduce solids into their baby’s diet. It is very rarely seen in an exclusively breastfed baby. It causes inflammation in the baby’s gut and presents with profuse vomiting, pallor and floppiness about 2-4 hours after eating the allergen. It can easily be confused for gastroenteritis, or another serious illness, and it may not be until the second or third event that the diagnosis of FPIES is considered.

The most common allergens are rice, dairy, and soy, but actually any food protein is a potential trigger in susceptible babies. Luckily, most babies become tolerant to the allergen by school age.

Treatment involves exclusion of the particular allergen. It may take some trial and error to figure out which food protein is the trigger and unfortunately there are no tests that will give us the answer. Although the reaction to the allergen can be scary, there is no link with FPIES and anaphylaxis.


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