Brief Answer:
You may formula feed for few days

Detailed Answer:
Hello

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Breastfeeding is the best feed and all the measures should be taken for enough milk production. During initial days the amount of milk(thick and yellow milk called colostrum) production is less and is sufficient to meet the demand of the baby.

This milk is enriched in immunoglobulins and must be given to baby as it helps in building the immunity.

Awareness, willingness and confidence in mother is very crucial for enough milk production. Active support,encouragement of mother with use of proper technique and attachment is also important.
Adequate nutrition during the lactation period is also important.

So, in summary try your best for the breast feed.You have mentioned that serum bilirubin is 13-15.This level of bilirubin does not need any treatment but it may be due to decreased feed.

The adequacy of feed can be assessed by frequency of urine output (4-6 times a day), baby should not cry and sleep at least 1-2 hour after the feed and weight gain.

Mother can also be given medication like Metroclopramide to increase the milk production.
Even after all the measures if baby is not getting enough milk then formula feed can be given.You may give lactogen 1 as it is tolerated well by most of the babies.

First try for breast feed(more the baby sucks more the production of milk),give the formula feed by katori spoon thereafter.Avoid using bottle feed as this may cause nipple confusion.Take proper care about the dilution and hygiene.

As the breast milk production incraeses stop giving formula feed.

I hope this helps.
Please let me know if you have any more query.
Regards

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