What should I do if my baby hasn't had a bowel movement for 3 days?

Patient's question:

All symptoms: The baby has not had a bowel movement for 3 days and has been passing gas more frequently. Diet and sleep are normal. A few days ago, the doctor used glycerin suppositories once. Now, the baby still hasn't had a bowel movement and is consuming 300 ml of formula per day. Premature at 34 weeks, weighing 4 pounds.
Onset and cause of illness: December 12th to 15th
Treatment: December 11th, the doctor prescribed glycerin suppositories and oral multivitamin solution. On December 12th morning, the baby used glycerin suppositories and had a bowel movement (the stool was not dry, but relatively loose). Since then, the baby still hasn't had a bowel movement.
Help needed: I want to know what the reason is and whether it is normal.

Doctor's answer:

Hello
First, you can use infant glycerin suppositories or soap sticks. But be a little gentle with the action.
Additionally, I suggest:
1. Drink more water—make sure to drink more water. You can add milk supplements to formula or water, using one package per day. Formula and breast milk should not be combined with calcium; they should be spaced apart by 2 hours. Otherwise, it may also cause constipation and affect the absorption of milk and calcium. Not only will it be ineffective, but it may also lead to severe side effects.
2. For breastfed babies, mothers should adjust their dietary structure, eat lighter, and drink more water.
3. Massage the baby’s abdomen in a clockwise direction. Gently rub the infant’s abdomen with the palm of your hand, centered around the navel, rotating from left to right. Massage 10 times, rest for 5 minutes, then massage another 10 times, repeating the process 3 times. Abdominal massage can promote gastrointestinal blood circulation, increase intestinal peristalsis, not only making bowel movements smoother but also improving the baby’s appetite.