At about a month the poop frequency for both breast fed and formula fed babies slows down. Breastfed babies can go a few days without pooping where formula fed babies usually slow down to once a day ... but all babies are different. I think with formula fed babies the poop should be the consistency of peanut butter (gross, eh?) but not super firm. If your baby goes more than 3 days without pooping you should call your pediatrician (this is for formula fed babies).

The grunting to poop... crying or straining is all normal. It doesn't mean she is constipated unless her poop is pellet like or hard. But be careful because formula-fed babies tend to get constipated easier than breast fed babies.

The green poop ... is your formula iron-fortified? That can cause green poop ... but ask your doc.

If your baby acts uncomfortable during feedings or after ...call your doctor.

But if the poop is softish, if she goes once a day or so, and if she seems generally happy, I wouldn't worry.

I have been told by pediatricians that formula fed babies can go up to three days without one.

I"m only a VERY brand new mum, my little one is only 6 days but she's amazing and she's formula fed, some reading up that the nurses gave me says formula fed babies should have a bowel movement at least once every 2 days. So you should be fine, and my mum has warned me about the tar-like poop so i'd say thats normal too, Some recommendation they gave me for constipation in formula fed babies is to offer bab 30ml of cooled boiled water once or twice a day, or offer 1 teaspoon of brown sugar in 20-30 mls of water twice a day, or offer 10-15ml of prune juice in 20-30 mls of water twice a day.

Good luck! xx