Assorted baby bottles.

All about baby bottles and nipples

A guide for moms getting started with formula

Your baby will show you which bottle and nipple she prefers

Finding the right baby bottle is more a process of elimination than a matter of personal preference — at least for you. Your baby will ultimately decide which is best, so be prepared to try more than one style of baby bottle and nipple.

Selecting a baby bottle shape, material, and size

You will find baby bottles in many styles: some with liners and some without; bent and straight; glass and plastic. Before you choose one to try, or several, it helps to understand why there are so many options.

Baby bottle shapes: standard or bent

  • Standard (straight, with no bend) baby bottles have been successfully used for years.
  • Bent baby bottles, and those with liners, are designed to reduce the amount of air your baby will swallow, which can cut down on gas and fussiness.
    • Baby bottles with disposable liners are easy to clean, but the liner refills can be costly.

Baby bottle materials: glass or plastic

  • Glass baby bottles are sturdy and easy to clean, but they are heavy and can shatter when dropped.
  • Plastic baby bottles are lightweight and shatterproof, and many are free of BPA.

Baby bottle sizes: small for now, larger for later

Smaller bottles (4 ounces or less) are nice when your baby is small, but you'll need to replace them with larger bottles as your baby grows. On the practical side, be sure the bottles you choose will fit into the pouch of your diaper bag.

Baby nipple sizes, shapes, styles, and materials differ by design

Nipple shapes, sizes, and flow speeds need to mesh with your baby's sucking style, so it is important to experiment to find the right one. If the hole is the wrong size, it might cause your baby to feed too quickly or too slowly, or to swallow too much air.

The size of the hole determines how quickly or how slowly the milk flows. Some nipples are labeled with sizes.

Baby nipple sizes

  • Size one nipples are for babies from birth to age 6 months and have a small hole.
  • Size two nipples have a larger hole and are for older babies.
  • Special nipples for preemies also are available.

The ideal bottle nipple will allow a few drops of milk to fall out as soon as you turn the bottle upside down, and then the dripping should stop. If you think the milk is flowing too quickly for your baby, try a nipple with a smaller hole. If you think your baby is getting frustrated from having to suck too hard, try a nipple with a larger hole.

Baby nipple shapes

  • Standard nipples are tall and dome-shaped.
  • Orthodontic nipples are shaped to fit the inside of your baby's mouth — wide at the tip and base, and narrow in the middle.
  • Other nipple types mimic the shape of your breast.

Baby bottle nipple materials

Bottle nipples typically are made of latex or silicone.

  • Latex is softer and can hold the odor of the milk, and tends to wear out more quickly.
  • Silicone is sturdier and easier to clean, but is not as soft as latex. However, silicone nipples last up to a year.

When to clean and replace baby bottles and nipples

Before using any new bottles or nipples, wash them in hot, soapy water or in the dishwasher. Wash them again after every feeding, and check the bottle nipples for wear and tear. Be sure to replace nipples as your baby grows and needs a larger size, and always replace any bottle nipple that shows signs of wear.

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