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Baby weight is a vital little piece of information everyone loves to know when a baby is born. For you the quickest weight lost you’ve probably ever had and an end to a long running family sweepstake. A baby’s weight will provide care givers with information to your baby’s growth and development through their childhood. Here’s what you should know about your breastfed baby’s weight gain.

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Breastfed baby weight gain | A guide for nursing moms on your breastfed baby's growth and weight. Find out what's normal and what's now for your baby. Great tips for first time moms. Stork Mama

When should my baby be weighed?

Your baby will first be weighed within the first few hours after delivery. Once you are discharged from hospital or birth center you should register you baby with a pediatrician or family doctor. Within the first year baby should receive regular health check-up, including weighing, at:

  • 3-5 days
  • 1 week
  • 1 month
  • 3-4 months
  • 4-6 months
  • 9 months
  • 1 year

You can purchase your own baby weighing scales for use at home. If you purchase home use scales be sure to get them calibrated. This will ensure you are given accurate weights and not being caused unnecessary worry.

Breastfed Baby Weight Gain – What to Expect

The first week

In the first 3-5 days it’s normal for your baby to lose up 10% of their birth weight. For example a baby born weighing 7lb 6oz (3345g) can lose up to 11.7oz (334.5g). This normal weight loss is due to:

  • Passing meconium (baby’s first poo)
  • Adjusting to feeding (without a constant supply for the cord)
  • Water weight

The average is around 5-7% with few babies losing more than this. If you baby does loses 7-10% more than this, it’s still within a normal range for a breastfed baby. However your pediatrician or family doctor may want to investigate further into your baby’s feeding or health.

If you baby loses more than 10% of their birth weight, you will be advised to give baby supplemental feed of formula. The main concern with this much weight loss is you baby becoming dehydrated. You may also want to consult with a lactation specialist help with any breastfeeding issues.

Two weeks old

When breastfeeding is going well, your baby should be back to their birth weight by 10 days to 2 weeks.

It may take longer for baby to regain weight if they

  • Lost a high percentage on day 3-5
  • Were premature
  • Have feeding problems
  • Have health issues

If the issue is a breastfeeding problems, you need to have them addressed immediately. Ongoing breastfeeding problems can take longer to fix and may cause long term health issues for both you and baby.

Read Now: The Best Baby Weight Scales For Breastfeeding

Three to four months

This is a time of rapid growth for your baby. For the first 3-4 months your baby should gain, on average, 6oz (170g) per week. Depending on circumstances it can be acceptable for your baby to gain around 4oz (113g). You should always be kept informed from your health care provider, as whether your baby’s weight gain is normal or low.

Four months to one year

The rapid growth seen in the first 4 months will begin to slow down at this age. These are the average weight gains for breastfed babies at:

Four to Six months – 4-5oz (113 to 142g) per week
Six to Twelve months – 2-4oz (57 to 113g) per week

By the time your baby is one year old, they should typically weight around 2.5 times their birth weight.

Using weight growth charts

Growth charts can be useful to give you an idea of roughly where you baby should be at each stage, they are often gender based. Growth charts are good for keeping track of weight gain over a period of time, However they shouldn’t be followed to the letter as there are some shortcomings.

Factors which influence weight gain which growth charts don’t take into consideration:

  • Genetics
  • Ethnicity
  • Geography
  • Race

One of the biggest drawbacks for using growth charts with breastfed baby weight gain, is that the information is based on studies from formula fed babies who were weaned at 4 months. An exclusively breastfed baby will follow a different growth pattern.

When compared to formula feed babies, Breastfed babies:

  • Gain weight slower between 4 month to 1 year
  • Are leaner at one year old
  • Drink 20% less milk (due to nutrient rich breast milk)

If the pattern of growth on your baby’s chart seems sporadic then you may want to review how well baby is feeding. Good nourishment is essential for baby to grow and develop.

Monitoring hydration

Skin – A hydrated baby should have soft plump skin. If your baby’s skin were to be pinched it should return to normal quickly and not stay pinched. Baby’s eyes and mouth should always have a soft, moist appearance.

Wet Diapers – With a new born the number of wet diapers should equal the number of days after birth. So day one expects one wet diaper, day 2 expects two wet diapers etc. After day five your breastfed baby should level off at 6 wet diapers per day. Disposable diapers can be difficult to judge with as they are so absorbent. Try placing a piece of cotton wool in the diaper which will be soaked when wet.

Dirty Diapers – If your baby is properly hydrated you will notice their poo changing color with each nappy of the first few days. It starts as black (meconium) then changes to a brown/green and finally to yellow. Once the diapers turn yellow, expect around 3-4 dirty diapers a day. Just a word of warning, breast milk has laxative properties, so it’s normal for them to be explosive!

Signs of dehydration

If your baby is not meeting the minimum diaper numbers as suggest above, you need to be vigilant for other sign of dehydration. You baby will need more fluids if they are:

  • Listless
  • Lethargic
  • Have a weak cry
  • Skin remains in place if pinched (or goes down slowly)
  • Dry mouth
  • Dry eyes
  • Have a sunken look to the top of the head (on the soft spot)
  • Have a fever

If you notice these signs you should contact your doctor immediately.

When you need help

If your breastfed baby is slow to gain weight or failing to grow you should be receiving regular follow ups from your doctor or a pediatrician. The first post of call will be to give baby supplements. This will usually be in the form of expressed breast milk. In certain circumstance you may need to give a specialist formula (usually health related) or for older baby’s weaning may be suggested.

You should begin to see an improvement in baby’s weight gain as soon as you begin supplementation. If you don’t you may need to up the volume, but always discuss any changes with your doctor first.