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Dad’s Question:

Our baby has gone from breastfeeding to formula and has been on formula for 7 days now. She is eating about 3-4 oz 7-8 times a day, and tonight she had a really smelly, runny green poop, that shot out of her bum while the diaper was off. Is she possibly getting too much formula?


Baby Helpline:

Watery, Smelly Poop In Newborn

It doesn’t sound like there is much of a problem here. If your baby was only breastfed for three days, it is not possible to compare the stools now when formula-fed with before. Mom doesn’t produce much breast milk in the beginning and the baby doesn’t really eat much until at around 5-6 days old.

It is normal for a baby’s poop to be watery because their whole diet is liquid. Formula-fed babies often do have somewhat more solid poop than breastfed babies, but it varies a lot. The consistency of her poop will not be related to how much she eats – but possibly to what she eats.

Don’t worry about giving your baby too much formula. (Unless you mean too much formula in relation to breast milk if your wife still breastfeeds too; breast milk is easier for the baby to digest.) At your baby’s young age, their appetite and how much they need to eat actually increases day by day and it is very important as a parent to not hold back if the baby seems to be hungry. They grow and develop at an amazing speed and need to eat frequently.

The color of the poop isn’t something to worry about unless it is red or black, which means that there is blood in it, and in such case, a doctor’s consultation is definitely needed.

The smell is probably due to the formula; studies have shown that formula poop is a lot more smelly than breast milk poop. (Yes, there are actually research studies on this! :-) )

As for the projectile poop, this is probably caused by gas which builds up in the bowels behind the poop sometimes and comes out at a very inconvenient moment. (Happens to most parents once in a while…)

If your child’s stool is watery and accompanied by fever or persistent vomiting you should go to the doctor immediately. Also, if your baby spits up a lot or gets rashes while eating, you might want to discuss it with a doctor, as it could indicate milk protein allergy or lactose intolerance. Otherwise, as long as your baby is pooping and happy there is nothing to worry about.

I hope this helps,

Newborn Poop Issues

Comments for 10 Day Old Had Green Watery, Shooting Poop

Feb 11, 2018Green poop
by: Anonymous
Have your doctor check the stool for blood. It sounds like a milk protein allergy.

Apr 10, 2018Going to Soy Lactose-Free Formula
by: Anonymous
I am going through this right now with my 6-week old son. He was on gentle ease formula because he is gassy and spits up a lot. So the doctor put him on soy lactose-free formula because his poop was green and watery and he was spitting up a lot of his milk. He doesn’t spit up hardly at all now but now he has really hard poop and cries a lot because it hurts him to go to the bathroom. Hope this helps.

Feb 28, 2019Lactose-free
by: Darina
My daughter is 8 weeks old and was really gassy, with green smelly mucousy poop. We put her on a lactose-free formula for now. It seems to help. She is breastfed so we figured it is lactose overload (too much foremilk that contains a lot of fat and lactose). We decided to keep her on this formula for now till we go to see our doctor in a few days

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