The majority of newborns are exclusively breastfed during the birth hospitalization, and weight loss is nearly universal for these neonates. The amount of weight lost varies substantially among newborns with higher amounts of weight loss increasing risk for morbidity. No hour-by-hour newborn weight loss nomogram exists to assist in early identification of those on a trajectory for adverse outcomes.
For 161 471 term, singleton neonates born at ≥36 weeks’ gestation at Northern California Kaiser Permanente hospitals in 2009–2013, data were extracted from the birth hospitalization regarding delivery mode, race/ethnicity, feeding type, and weights from electronic records. Quantile regression was used to create nomograms stratified by delivery mode that estimated percentiles of weight loss as a function of time among exclusively breastfed neonates. Weights measured subsequent to any nonbreastmilk feeding were excluded.
Among this sample, 108 907 newborns had weights recorded while exclusively breastfeeding with 83 433 delivered vaginally and 25 474 delivered by cesarean. Differential weight loss by delivery mode was evident 6 hours after delivery and persisted over time. Almost 5% of vaginally delivered newborns and >10% of those delivered by cesarean had lost ≥10% of their birth weight 48 hours after delivery. By 72 hours, >25% of newborns delivered by cesarean had lost ≥10% of their birth weight.
These newborn weight loss nomograms demonstrate percentiles for weight loss by delivery mode for those who are exclusively breastfed. The nomograms can be used for early identification of neonates on a trajectory for greater weight loss and related morbidities.
Comments
Curious.
This is an impressive and thorough analysis of newborn weights after both vaginal and surgical births.
One question: what was the mother's IV fluid intake during labor?
Chantry et al. (2011 Pediatrics; 127:e171-179, "Excess Weight Loss in First-born Newborns Relates to Intra-Partum Fluid Balance"),Hirth et al. (2012 Clinical Lactation;3:59-63 "Maternal average IV ml/hr positively correlated with infant maximum weight loss") and Noel-Weiss et al. (Int BF Journal 2011;6(9) "An observational study of associations among maternal fluids during parturition, neonatal output, and breastfed newborn weight loss.") all relate the newborn weight loss with administration of IV fluids in labor. Dr. Noel-Weiss suggests not counting the newborn weight until 24 hours after birth, as she describes newborns having a first day of diuresis, so the accurate (dry) weight wouldn't be until 24 hours of age.
Was maternal IV fluid balance considered as a variable in this study?
warmly, Nikki Lee
Conflict of Interest:
None declared
Concerns about the new nomogram on normal weight loss in exclusively breastfed babies
I have grave concerns about endorsing the new nomogram for weight loss in exclusively breastfed babies as the new acceptable standard. Weight loss has been documented to predict hyperbilirubinemia and dehydration at percentages much less than described in the nomogram. Yang et al. (BMC Pediatrics 2013, 13:145) found a percent weight loss of 4.5% at 24 hours, 7.6% at 48 hours and 8.15% at 72 hours predicted development of significant hyperbilirubinemia (> 15 mg/dL) within 72 hours after birth. Endorsing a nomogram that accepts greater than 10% as normal without providing any data on safety such as rates of jaundice, dehydration, hypernatremia and long-term neurological outcomes from prolonged fasting states would potentially result in greater harm. We need to study the safety of what we consider "normal" before endorsing it as such.
Conflict of Interest:
None declared
Mode of delivery and postnatal weight loss: The role of arginine-vasopressin
With great interest, we read the article by Flaherman et al. demonstrating increased postnatal weight loss in exclusively breastfed infants born by cesarean section, as opposed to those born vaginally, the difference becoming evident as early as 6 hours after delivery.(1) The authors and the accompanying editorial attribute the differential weight loss observed to protracted onset of lactation after cesarean section, as compared to vaginal delivery. During vaginal delivery, there is a huge surge of maternal oxytocin that also promotes milk production which is absent in women with elective and reduced in women with secondary cesarean section. We would like to point to another mechanism behind the observed difference in weight loss. Apart from enteral intake, postnatal weight loss is also determined by urinary loss of fluid. Urine output is under the control of another peptide released from the posterior pituitary, arginine-vasopressin, also known as anti-diuretic hormone. While the short half-live of arginine-vasopressin renders attempts to determine its plasma concentrations challenging, the stable by-product generated during endoproteolytic release of arginine-vasopressin, copeptin, is increasingly being used to estimate arginine-vasopressin release. Several investigators have found that copeptin umbilical cord blood concentrations of infants born vaginally exceed those born by cesarean section more than 100-fold.(2 -5) There is in fact no other medical condition known with such high levels of circulating copeptin as that of a normal human infant just born by vaginal delivery. Notably, copeptin concentrations at birth are inversely related to postnatal weight loss by day 3 of life.(2) Viewed from a teleological standpoint, reducing urinary water loss at birth until enteral supply picks with the establishment of lactation appears as a prudent strategy, and cesarean section without any previous labor deprives the newborn infant of the wave of fetal arginine-vasopressin serving as a preemptive adaptation.
1.) Flaherman VJ, Schaefer EW, Kuzniewicz MW, Li SX, Walsh EM, Paul IM. Early weight loss nomograms for exclusively breastfed newborns. Pediatrics. 2015;135(1):e16-23. 2.) Wellmann S, Benzing J, Cipp? G, Admaty D, Creutzfeldt R, Mieth RA, Beinder E, Lapaire O, Morgenthaler NG, Haagen U, Szinnai G, B?hrer C, Bucher HU. High copeptin concentrations in umbilical cord blood after vaginal delivery and birth acidosis. J Clin Endocrinol Metab. 2010;95(11):5091-6. 3.) Schlapbach LJ, Frey S, Bigler S, Manh-Nhi C, Aebi C, Nelle M, Nuoffer JM. Copeptin concentration in cord blood in infants with early-onset sepsis, chorioamnionitis and perinatal asphyxia. BMC Pediatr. 2011;11:38. 4.) Benzing J, Wellmann S, Achini F, Letzner J, Burkhardt T, Beinder E, Morgenthaler NG, Haagen U, Bucher HU, B?hrer C, Lapaire O, Szinnai G. Plasma copeptin in preterm infants: a highly sensitive marker of fetal and neonatal stress. J Clin Endocrinol Metab. 2011;96(6):E982-5. 5.) Smith J, Halse KG, Damm P, Lindegaard ML, Amer-W?hlin I, Hertel S, Johansen M, Mathiesen ER, Nielsen LB, Goetze JP. Copeptin and MR-proADM in umbilical cord plasma reflect perinatal stress in neonates born to mothers with diabetes and MR-proANP reflects maternal diabetes. Biomark Med. 2013;7(1):139-46.
Conflict of Interest:
None declared
Weightloss >= 10% of birthweight = Decaphobia. Decaphobia: A One-Act Play
Weightloss >= 10% of birthweight = Decaphobia
Decaphobia: A One-Act Play
Cast:
Pediatric intern
32-year-old nursery attending
50-year-old pediatrician
Scene Hallway of a postpartum unit at almost any hospital
Time: Any time in 2015
Intern: -- (to the attending) This is a 3-day-old term, non- jaundiced, exclusively breastfed infant born via C-section weighing 3500 gms. Today's weight is 3115 gms, down 11% from birthweight. In the past 24 hours, she has voided three times and passed two soft, brownish stools. The vital signs are stable, the physical examination normal.
Attending: -- Start supplemental formula.
Intern: -- Why?
Attending: -- (dismayed) Because the baby has lost more than 10% of birthweight, which is associated with an increased risk for dehydration, hypernatremia and hyperbilirubinemia.
Intern: -- In preparation for this rotation, I could not find evidence supporting formula supplementation in otherwise healthy breastfed babies who lost more than 10% of birthweight. This mother notices her breasts feeling fuller today and hears the baby swallowing. The infant is feeding every 2-3 hours, and is satisfied between feedings and sleeping. On examination, she is well appearing and well hydrated. These findings do not support your fear about the weightloss.
Attending: -- What source are you using? You cannot trust everything you read on the internet.
Intern: -- I read several articles and textbooks looking for evidence supporting the 10% weightloss cut-point. Most made a statement regarding 7% or 10% weightloss as the critical cut-point acknowledging there is limited evidence.
Attending: -- What is the big deal about supplementing with formula?
Intern: -- Our hospital is moving toward becoming Baby Friendly and #6 of the 10 steps is "Give infants no food or drink other than breastmilk, unless medically indicated."1
Attending: -- Is there anything else? I suspect that you have more since the browser on your tablet remains open.
Intern: -- A recent article by Flaherman et al indicates that by 72 hours of life, more than 25% of babies born by C-section lose atleast 10% of their birthweight. Their article showing weightloss nomograms for newborns is an important contribution to the literature.
Attending: -- You have convinced me to hold off on formula and to have our lactation consultants continue working with the mother. The infant should follow-up in 2-3 days with their pediatrician as per American Academy of Pediatrics recommendations.2
Older pediatrician: -- (after listening in, now addressing the intern) Your conversation reminds me of an article I read as an intern. The article discusses vigintiphobia, meaning the "fear of 20" in association with hyperbilirubinemia.3 Sounds like you are debating decaphobia, or the "fear of 10." Weightloss exceeding 10% of birthweight is well described, but not necessarily healthy or safe. We should all have a healthy degree of decaphobia since hypernatremia and hyperbilirubinemia are real concerns. Moritz et al demonstrated that most newborns with hypernatremia presented with jaundice and/or appeared sick,4 and van Dommelen et al showed that hypernatremic newborns typically had low weight for more than one day.5 As you say, it is most important to consider factors other than weight when deciding whether to use formula. Keep up the good work!
Malinda Wu, MD Penn State Hershey Children's Hospital, Pediatrics Resident Hershey, PA
Esther K. Chung, MD, MPH Nemours and The Sidney Kimmel Medical College, Thomas Jefferson University Philadelphia, PA
References
1. Baby-Friendly USA. Guidelines and Evaluation Criteria for Facilities Seeking Baby-Friendly Designation. Sandwich, MA: Baby-Friendly USA, 2010.
2. Geoffrey RS, Cynthia B, Graham AB, 3rd, et al. 2014 recommendations for pediatric preventive health care. Pediatrics. Mar 2014;133(3):568-570.
3. Watchko JF, Oski FA. Bilirubin 20 mg/dL = vigintiphobia. Pediatrics. Apr 1983;71(4):660-663.
4. Moritz ML, Manole MD, Bogen DL, Ayus JC. Breastfeeding-associated hypernatremia: are we missing the diagnosis? Pediatrics. Sep 2005;116(3):e343-347.
5. van Dommelen P, Boer S, Unal S, van Wouwe JP. Charts for weight loss to detect hypernatremic dehydration and prevent formula supplementing. Birth. Jun 2014;41(2):153-159.
Conflict of Interest:
None declared