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Pediatrics/Poor Weight Gain


QUESTION: My son is almost 4 months old and is struggling to gain weight. He was 7 lbs 4 oz at birth and is only 11.5 lbs now. He was exclusively breastfed until 2.5 months when we started giving him some formula to help him gain. Currently, he nurses in the morning, has 3 5.5 oz bottles during the day and nurses 2 times in the evening. He sometimes nurses in the middle of the night as well. After he nurses in the evening, we offer him a bottle of formula. He usually takes 1-2 additional ounces.  He is an extremely happy, content baby. He babbles, rolls over, belly laughs and smiles all the time. Our pediatrician is watching him and working with us but I am very worried. What else should I be doing?

ANSWER: Hi, Tabitha,

Assuming he is normal from an exam and developmental point of view, and is not vomiting or losing calories by having a lot of stools, he probably is fine.  I suspect he is not getting as much breast milk as you would think.  I would offer him additional formula after every nursing for a week or so and see how much he takes.  It is hard to think that anything is really wrong in this healthy baby that you describe.  Be sure everyone in the family gets flu shots to protect him this influenza season.

Good luck, Dr. Olson

---------- FOLLOW-UP ----------

QUESTION: Thank you.  I mentioned your answer to my husband and he said I should have also mentioned the following.  His right eyelid is a little droopier than his left and his left pupil is often quite a bit larger than his right.  It varies but sometimes his left pupil is really dialated.  We all have our flu shots :) Thanks again.


It is common to have one pupil larger than another as a normal variation.  We call this anisocoria.  
This is something that is present usually from birth, although it can be more evident as the eyes change color.  The eyelids can also be normally droopier on one side. Bodies are seldom absolutely symmetric.  Both of these findings should be discussed with your doctor and followed, for both of them, of course, could rarely be signs of significant problems that you would want to know about.

Good luck, Dr. Olson


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David Olson, MD


I would be happy to attempt to answer any questions about general pediatric topics, either medical issues or behavioral issues. This would include all the various questions one receives in a busy pediatric practice. I`m a board certified pediatrician in northern Michigan and have been in practice for over 15 years. I enjoy the teaching role I have in our practice and would enjoy the opportunity to help others with their pediatric problems.

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