Before You Panic About Newborn Weight Loss…

Many years ago, I heard renowned physician and author Dr. Ruth Lawrence repeatedly urge all of us within earshot to “Look at the whole clinical picture.” Whether it was weight loss or anything else, she warned, “It’s just one data point.” Perhaps an important data point, but still, just one data point. In my recent interview with experienced pediatrician Dr. Jennifer Thomas, she used different words, but preached the same message: look at newborn weight loss “in context.”

In her blog post, Dr. Jen wrote that neonatal weight loss can be interpreted in context by looking at the baby, the labor history, stool output, the scale, and the feeding assessment. That sentence caught my attention. I want to expound upon each of those points.

The baby

What do we know about the baby? Is the baby full term, or late preterm, perhaps? (And we don’t see many post-term babies these days, but they tend to eat as if there is no tomorrow!)

Does the newborn have some clinical condition that makes a weight loss look more ominous, or is he basically a healthy baby who can power through a feeding slump until tomorrow? Has the baby had ample opportunity to nurse, or is he stuck in a room 40 feet from his mother?

Labor history

Here in the United States, laboring mothers typically have an epidural infusion, with liter after liter of IV fluid. This fact is crucial to understanding newborn weight loss in the first few days.

When we weigh the baby immediately after delivery, we assume that’s his baseline weight. But it is not. Years ago, I read Dr. Chantry’s fabulous study. She posits that the newborn has “water weight” at birth, resulting in many wet diapers and subsequent weight loss.

That’s just the tip of the iceberg for labor/delivery issues.

Stool output

I go on the assumption that urine output in the first few days doesn’t tell us much about newborn weight loss. But stool output does. Why so?

Breastfed infants take in oligosaccharides. (I’ve addressed this elsewhere, and Dr. Kirsty LeDoare had much more to sayabout oligosaccharides.) Oligosaccharides, because they are non-digestible, are eliminated in the stools. Hence, newborns who ingest greater amounts of oligosaccharides have more stools.

Using the scale

In one hospital, we first weighed the baby in the labor/delivery area on the second floor; the next day, we weighed him in the nursery or mother-baby unit on the third floor. If the weight loss seemed excessive, the nurse was not likely to traipse in and out of the elevator to check the “other” scale. But different scales often register differently.

To determine newborn weight loss, three elements must be accurate: technique, equipment, and trained measurers.

• Technique includes issues such as weighing the newborn with the same clothes (or nude) each time.
• Electronic equipment must be calibrated and used correctly. (Presumably, no one is using the ancient balance scales.)
• Trained measurers who know how to deal with an especially wiggly baby, or who check to see that some odd nearby item is not registering on the scale.

In one study, only 16 of the 152 scales used were accurate. Yet, Schlegel-Pratt asserts, “Errors in weighing technique, reading the scale and recording the weight undoubtedly contribute to incorrect results, but often the scale itself is blamed.” Dr. Alsop-Shields and colleagues tell us that “it is well known…that these measurements are fraught with error.”

I totally agree, because I’ve seen it. The nurse can and does sometimes read the scale without her glasses on, or she transposes a number when she documents the weight. She might even record it on the wrong kid’s chart!

Good assessment of the feeding can predict newborn weight loss

As my beloved friend and ultra-knowledgeable colleague, Debi Bocar, RN, Ph.D., IBCLC, always reminds parents and professionals, “Mouth on breast does not equal breastfeeding. Audible swallowing equals breastfeeding.” How true!

Audible swallowing is not the only indicator of good milk transfer. Some newborns swallow milk, but not consistently, or not enough to meet their needs.

But if you do NOT hear audible swallowing during the feeding, it’s because the baby is not taking in milk! If the baby is not swallowing milk now, you will absolutely NOT see results later in the diaper or on the scale.

I want to reinforce what Dr. Jen said: We can’t be cavalier about newborn weight loss. But whatever your alarm number is — 7% or 10% or whatever it is at your hospital — remember that it needs to be seen in context of the factors listed above.

What’s your take on this? Let me know in the comments below.