In Part I of The Impact of Common Labor Interventions on Newborn Weight Loss and Breast/Chestfeeding Cessation, we examined how the use of analgesics for pain relief, Pitocin for induction and a large IV fluid load delivered throughout labor, can lead to breast/chestfeeding challenges for new parents in the first few hours and days of life.  In Part II, we examine the appropriate timing of a newborn’s baseline weight assessment and other factors for determining overall health.  

When, after birth, should a newborn’s baseline weight be established?  Using a weight that may have been impacted by labor interventions can hinder maternal breastfeeding confidence and skew pediatric goals for normal newborn weight gain.

Wait on the weight?

After the baby is born and presuming they are stable, weight gain is the key indicator of a thriving baby.  Most babies will be weighed within an hour or two after birth and that birthweight will become the baseline against which all future weight measurements will be compared.  But how accurate is that first birth weight? 

In 2011, a study (Noel-Weiss, J., et al, 2011) suggested that the baby’s birth weight should be recorded at the 24 hour mark instead of at birth if the parent had received IV fluids during labor.  In the study, there was a positive correlation between the baby’s output (wet diapers) in the first day of life, the amount of IV fluid the parent received in the two hours before birth and newborn weight loss at the 24 hour mark. 

However in 2025, a meta-analysis of 8 randomized control trials (totaling 1727 women) found that there was no significant difference in birthweight between women who have received IV fluids at a rate of 125ml per hour vs a woman who received twice as much (250ml per hour). They concluded that when IV fluids were given within ‘typical clinical ranges’, birthweight was not meaningfully altered. 

Further analysis (Watson et al, 2012) suggested that women who receive greater that 2500ml of fluid in total during the labor had babies more likely to surpass significant loss status.  Interestingly when I worked in a Pediatric Lactation Clinic, we did not look at the Mother’s total fluid load in labor when considering infant weight loss – nor did most women  know how much fluid they received and for how long.  This makes it difficult to determine if the weight loss is real or water weight.

So how do we tell how accurate the birthweight really is?  Most clinicians agree that weight should be recorded at birth and also again within 24 hours.  Many feel that the 12 hour weight is the most accurate for determining weight change against the 72 hour mark. 

In searching for answers, many parents splash out on expensive scales and take it upon themselves to weight the baby daily.  Although this can bring relief, it is more likely to cause stress and panic if a baby is not gaining 0.5-1.0 ounces per day after Day 3.  Also, clinical scales are usually accurate to a few grams and are recalibrated and serviced routinely whereas retail scales are not.  Perhaps a better solution to daily weighing is to educate parents on the expected amount of wet and dirty diapers in the first weeks. 

I encourage parents to “let the poop give you the scoop” since diaper counting is a more useful indicator of overall health initially than weight loss.  Parents should prepare for bigger weight loss if the baby has more than one wet diaper on the first day of life.  For example, if a baby has five wet diapers in the first 24 hours, they are clearly offloading fluids – and a bigger weight loss should be expected by day 3.  Stools (dirty diapers) are also an important indicator and reflect a woman’s milk supply transitioning from colostrum to mature milk as the stool changes color from black/brown/green to mustard color.

There are many apps that help record diaper counts, minutes at the breast, volume of a bottle, etc.  Educators should encourage breast/chestfeeding parents to record the number of wet and dirty diapers in the first two weeks so that pediatricians can take all factors into consideration when deciding whether or not the baby has lost an excessive amount of weight.

What is considered normal weight loss?

In our “Breastfeeding with Success” class, parents learn that weight loss in the first few days is normal, but what is considered normal is debatable.  Most current clinical practice guidelines suggest that a baby who has lost more than 7% of their birth weight by day three needs intervention (American Academy of Pediatrics. First Office Visit, 3–5 Days. Updated February 13, 2026). Weight loss of  ≥10% is considered to be a sign of inadequate breast/chestfeeding and supplementing with pumped milk, donor milk, or formula immediately is the recommended course of action.  Weight loss in both scenarios is defined as the percentage of weight lost from the ‘first weight measured weight’ which is why the timing of the first weight-in is under discussion.

What else could affect normal weight loss?  In Part I, we highlighted labor interventions that could impact or delay the transition from colostrum to mature milk and lead to greater newborn weight loss.  In both the Noel-Weiss, et al study (2011) and a large 2015 study (Miller, J., et al), mode of delivery (vaginal vs cesarean section) was highlighted as another possible culprit.  The results concluded that babies born by cesarean are more likely to lose a higher percentage of weight in the first 72 hours compared to vaginal births – especially if they are breast/chestfed.

 Enter the nomogram

If the amount of fluid a baby sheds in the first 24 hours can skew the birth weight - and weight loss can have many underlying factors including both labor interventions and the mode of delivery - how do we really know if a baby is thriving and/or needs supplementation?  The results of a large four year study (Flaherman, VJ., et al, 2015) were used to create a database for weight loss comparison when a baby is exclusively breast/chestfed and delivered vaginally or exclusively breast/chestfed and delivered by cesarean section.

From that database, Penn State Health and Children’s Miracle Network created and released a handy tool called the Newt (newborn weight) nomogram which differentiates mode of birth for plotting and comparing weight fluctuation against the percent weight loss of other babies in the same situation.  The tool is similar to the ‘Bilitool’ (Bhutani, et al, 1999) which allows clinicians to plot a baby’s bilirubin levels.

The tool helps pediatricians (and parents) determine if the weight loss is within the acceptable range for their birth and feeding circumstances instead of urging the parent to supplement based on weight loss alone.  Another nomogram exists for formula fed babies.

 Key takeaways

Many factors affect the early days of breast/chestfeeding and newborn life. As labor becomes a distant memory and parents adapt to life with a newborn, the focus shifts to feeding and caring for the infant.  However interventions from the labor can have a continued effect on early latching, milk supply and newborn weight loss.  Weight loss, in particular, can be a huge stressor for new parents and negatively impact maternal confidence, leaving the parent to question their ability to appropriately feed and nurture their baby.  While newborn weight protocols and tools continue to evolve, parents need to keep all aspects of feeding and weight loss into focus.

As educators, our role is to support parents through education.  Discussing true birth weight parameters, encouraging parents to have the baby (re)weighed at the 12-24 hour mark and accurately recording the times and number of breast/chestfeeding sessions and diaper counts – can help clinicians and families come together to make decisions to help a baby thrive while not undermining the lactation relationship.

References

The Academy of Breastfeeding Medicine Protocol Committee. ABM Protocol 3: Hospital guidelines for the use of supplementary feedings in the healthy term breastfed neonate. Breastfeed Med. 2009;4:175–182.

Anisman E, Ehsanipoor RM, Saccone G, Berghella V. The association of intrapartum IV fluid rates during labor with birth weight. Eur J Obstet Gynecol Reprod Biol. 2025 Apr;307:268-270. doi: 10.1016/j.ejogrb.2025.02.040. Epub 2025 Feb 22. PMID: 40024847.

Bhutani VK, Johnson L, Sivieri EM. Predictive ability of a predischarge hour-specific serum bilirubin for subsequent significant hyperbilirubinemia in healthy term and near-term newborns. Pediatrics.1999

Flaherman VJ, Schaefer EW, Kuzniewicz MW, Li SX, Walsh EM, Paul IM. Early weight loss nomograms for exclusively breastfed newborns. Pediatrics. 2015;135(1):e16-e23. doi:10.1542/peds.2014-1532

Miller J, Flaherman V, Schaefer E, Kuzniewicz M, Li S, Walsh E, Paul I. 2015 www.hospitalpediatrics.org doi:10.1542/hpeds.2014-0143

Manganaro R, Mamì C, Marrone T, Marseglia L, Gemelli M. Incidence of dehydration and hypernatremia in exclusively breast-fed infants. J Pediatr. 2001;139:673–675. doi: 10.1067/mpd.2001.118880.

Noel-Weiss J, Woodend AK, Peterson W, Gibb W, Groll DL: An observational study of associations among maternal fluids during parturition, neonatal output, and breastfed newborn weight loss. Int Breastfeed J. 2011, 6: 9-10.1186/1746-4358-6-9

Thomson T., Hall W, Balneaves L, Wong S. Can. Nurse . 2009 Jun;105(6):24-8. Accessed 4.20.21: https://www.canadian-nurse.com/en/articles/issues/2009/june-2009/waiting-to-be-weighed-a-pilot-study-of-the-effect-of-delayed-newborn-weighing-on-breastfeeding-outcomes.

Watson J, Hodnett E, Armson BA, Davies B, Watt-Watson J. A randomized controlled trial of the effect of intrapartum intravenous fluid management on breastfed newborn weight loss. J Obstet Gynecol Neonatal Nurs. 2012 Jan;41(1):24-32. doi: 10.1111/j.1552-6909.2011.01321.x. PMID: 22834720.

About Mindy Cockeram

Mindy Cockeram is a International Board Certified Lactation Consultant and LCCE.  She has also been a guest contributor for Lamaze International since 2012.  She initially trained with the United Kingdom’s National Childbirth Trust (NCT), teaching both private classes and for the National Health Service at St Georges Hospital, London from 2004.  Currently, she teaches childbirth and breastfeeding for a large non-profit hospital in Southern California. She released Cut Your Labor in Half: 19 Secrets to a Faster & Easier Birth in 2017.  Two years later, she published Breastfeeding Doesn’t Have to Suck: Tips, Tricks and Knowledge for a Great Experience. Pump It Up! A Practical Guide to Confident & Efficient Breast Pumping was released in 2025.

Published: August 05, 2026

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