There are several good signs here: good weight gain, passing gas, and large, loose bowel movements. It doesn’t sound like a blockage to worry about. I often see babies go through a bit of a “poop transition” around this age. They seem to go from many stools a day, to only one or less. When I see a baby like yours in my office, and my exam doesn’t reveal any worry signs, then I try the following: if formula-fed, give the baby an extra 2 ounces of water per day (just add the water to one or two of her formula bottles). If breast-fed, I make sure mom goes off any cow milk products. Usually, these make the problem go away. If not, then time to go see the doctor.
“My infant (6 weeks old today) has had very difficult bowel movements the past 2 weeks. He struggles to poo a lot during the day, passes gas, but only has a bowel movement (huge and loose) every 2-3 days. We have given him glycerin suppositories a couple of the times because he seems so uncomfortable (screams while trying to poo). He is healthy otherwise and has gained 4 lbs since birth. Do you think there could be blockage of the colon of a sort? The straining to poo is what concerns me the most. Red, Red face and lots of noise with straightened legs.”