It's recommended that you replace a baby bottle every 4 to 6 months but you really don't need to do so unless the baby bottle is cracked, damaged or moldy etc.
There's no need to replace a baby bottle as long as it's been washed out properly and cleaned between uses.
I've always washed the baby bottles out as soon as I could after feeding my baby.
I would at least place them in the sink with some water and then once I got time during the day or evening I would wash the baby bottles out.
Baby bottles are made of durable plastic so there should be no need to replace the baby bottle unless you forgot to wash it and it molded really bad.
I used a bottle brush and cleaned the bottles and never had to replace them but I used the cheap baby bottles so it was not an issue if I did need to replace the bottle.
Bottle nipples don't usually go bad as long as they are cleaned properly and daily after use and as long as the baby is not chewing on the bottle nipple when they get teeth.
I've only had to replace bottle nipples once my kids had teeth and would chew on them but other than that I would simply wash them and only go up a size in nipples when needed.
The bottles also lasted until the baby was off the bottle.
Bottle nipples should last until the baby is off the bottle and most times you don't need to replace the bottle nipple unless it has been chewed on or you need to change the nipple size.
As long as you wash the bottle nipples daily after use and wash the bottles the nipples and bottles should last as long as the baby is on the bottle which is sometimes a year.
Bottle nipples turn pink due to marcescens which can rapidly grow in reconstituted, non finished milk formula and produce the pink pigmentation.
You can eliminate the S. Marcescens by washing the bottles and nipples in hot water at 158 F for 1 minute.
A baby that doesn't like bottle nipples may also chew on the bottle nipple or sputter or cough when feeding.
The signs that your baby is ready to go up a size in bottle nipples are the baby takes longer to finish the bottle, the baby sucks fast with not too many swallows and or the bottle nipple collapses or the baby gets fussy when eating.
Bottle nipples are sized for the age the baby they are meant for.
For example size 1 bottle nipples have a small hole which are meant for newborn babies and those that don't require a faster flow which is for ages birth to 3 months of age.
Size 2, size 3 and size 4 bottle nipples have much larger holes and are good for older babies above 3 months of age.
Special bottle nipples for premature babies are also available.
A bottle nipple is sometimes called a teat which is a flexible part of a baby bottle that allow the baby to suck on to get milk.
The teat or bottle nipple on a baby bottle contains a small hole that allows the milk and fluids to flow through slowly as the baby sucks.
The collar of the bottle goes over the nipple and screws onto the bottle to seal the nipple to the bottle.
There are different flow rates for nipples depending on the baby's age.
You can get bottle nipples that have a slow, medium, or fast flow rate.
These nipples are often numbered, 1 is the slowest flow.
Infants usually start with a smaller hole and slower flow.
You will increase the size as your baby gets better at feeding and drinks more.
A spout requires a bit more finesse than a nipple to draw out liquid.
It also supports your baby's transition from a suckling to a sucking drinking motion, which typically happens around the 6-month mark.
To support those first sips, we created a soft spout that's flexible and soft on gums.