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If you’re planning to express breast milk at some point with your new baby, you may be confused about when to start pumping.

There are three option you have:

  • In pregnancy
  • Immediately after birth
  • When your supply is established

The timing you choose will depend on your circumstances and each one has its own benefits and drawbacks. Let’s explore each on I detail to help you decide the best time for you.

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When to start pumping breast milk | Tips for breastfeeding moms on when to use a breast pump. Stork Mama

When To Start Pumping Breast Milk

1. Pumping In Pregnancy

It is possible to start expressing small amounts of colostrum in pregnancy. However, never  consider this until you are over 37 weeks (term). The effect of pumping can release hormones which can send you into pre-term labor. Therefore it’s best avoided before you are at term. Pumping in pregnancy isn’t routinely recommended as it’s not a reliable enough to build a milk supply. However it can be useful in certain circumstances.


Currently breastfeeding

If you are still breastfeeding an o older child whilst you are pregnant, expressing milk can help ease the transition to tandem nursing. You can use the expressed milk to wean your eldest off the breast. Or use as a backup if you are fatigued or your new-born is having a growth spurt.

Nipple leaking

Its common side effect of pregnancy to leak some colostrum as your breasts prepare for birth. Sometimes this can become excessive and you may need to wear breast pads or nipple shells. Learning how to hand express a few drops of colostrum whilst pregnant can help reduce any leaking incidents. We would not recommend using a breast pump regularly in this case as the stimulation may increase the amount of leaking.

Induce labor

Studies have shown that nipple stimulation in term pregnancy can help release labor inducing hormones. Oxytocin is the same hormone released whilst breastfeeding (or expressing) and in labor. You may want to try this if it looks likely you will be medically induced for going overdue.

Pump practice

If you have already purchased a pump and wish to express as soon as baby is born, you can practice beforehand. Most moms won’t get much milk with the first few pumps. Practice can help you feel at ease with the pump and understand all the functions to give you a heads start on getting good volumes when you get serious about pumping.

Diabetic moms

Some health care providers recommend pumping in late pregnancy for diabetic mothers. This is known as ‘colostrum harvesting’ to build a small supply for when baby is born. Babies born to diabetic mothers need to have their own blood sugars closely monitored, and formula tops ups are needed if they are too low. If you have a colostrum supply ready you can use this instead and avoid any formula use as a remedy.


Poor results

As mentioned above, pumping in pregnancy is not a reliable method for building a milk supply. Firstly you will only pump colostrum which is used only in the first few days after birth. Most moms will get very little milk if any at all, so don’t be discouraged if this happens to you. Your pregnancy hormone (progesterone) is designed to keep milk making to a minimum until your baby and placenta are out.

Won’t increase supply

Pumping in pregnancy will not have any effect on the volume of milk you make once baby is born. The only way to ensure a high milk supply if regular and effective feeding by baby.

2. Pumping after Birth

It is perfectly safe to start expressing breast milk as soon as baby is born. We recommend you start by hand expressing until your mature milk come in on day 3-5. Colostrum is the first milk you’ll produce in very small amounts. If you use a breast pump with colostrum it’s easy to lose a lot of it in the pump parts. Your mature milk will be produced in larger amounts and easier to collect with a pump.


Sleepy baby

Labor is hard work for babies, and can make them sleepy for a few days whilst they recover. It’s common for newborn to have one good feed at the breast and then become disinterested. You can encourage your bay back to the breast by hand expressing a few drops of colostrum and spoon feeding, then encouraging baby to nurse at the next feed.

Maintain supply

If you or baby experience any problems which affect feeding it may be impossible for you to continue directly nursing. By using a breast pump you can maintain your milk supply and prevent it from ‘drying up’. This gives you the option to still feed baby breast milk and to return to breastfeeding once the issue are fixed.

Avoid formula use

Some babies may be slow to gain weight for a variety of reasons. If your baby loses more than 10% of their birth weight by day 5, your doctor will recommend supplementation. If you are breastfeeding, expressed milk should be the first choice of supplementation before formula – unless a specialized formula is required. Early expression means you can get a head start on a supply for baby.

Improve milk supply

If you feel baby is not emptying the breast effectively or isn’t nursing enough during the day you can combine nursing and pumping to improve your low milk supply. In this case its best to nurse first until baby is satisfied, then pump for 5-10 minutes to empty the breast. You may also want to add in extra pump sessions between nursing if you feel like your supply is dropping.

Premature baby

If your baby is born premature, you will be encourage by the NICU to express milk for baby. Premature babies often have a poor suck reflex and find it difficult to feed or swallow effectively. The antibodies in breast milk will give your preemie the best start to life and ward off any infections which their poor immune system is prone to.

Fast let-down

Some moms experience a fast let down, which means your milk is ejected with such force, it causes your baby to choke, cough or splutter at the start of a feed. Problems may start to occur if baby refuses the breast as they want to avoid this happening. This milk contains a high level of lactose sugars which can cause your baby to be gassy, colicky or have bright green poo. Moms can express milk for a few minutes after let down, to avoids the forceful let down, then place baby onto the breast to continue nursing.


Small volumes

Your milk supply will take 4- 6 weeks to establish, and you may not express a lot of milk before then. Please note this does not mean you have a low milk supply, as expressed milk is not an indication of how much milk you make. Babies are much more effective at expressing the milk than hand or pump expression.

Nipple teat confusion

The WHO recommends that you don’t introduce a teat to your baby before your milk supply has established. Problem called nipple-teat confusion may occur. If your baby starts to refuse feeding at the breast as the action differs to bottle feeding. You may want to look into using a specialist teat for your bottles if you are concerned this may happen.


If you are known to have an oversupply of breast milk it is best to avoid extra expressing. Unless you can’t feed baby directly at the breast. Extra pump session in-between nursing should be avoided, and if you need to express its best to do this at the start or end of a feed. Extra expressing will stimulate your body to produce even more milk and can lead to problems such as engorgement.

3. Pumping When your Supply Establishes

If you have a term baby and intend to exclusively breastfeed, most breastfeeding consultants will advise that you do not express milk until you supply has established. For most moms this will happen 4-6 weeks after birth. An established supply is when your body makes the correct amount of milk for your baby.


Best results

Your body is accustomed to how much milk your baby should have and your will reduce the likelihood of oversupply or causing a drop in milk supply.

Baby can feed effectively

At this stage your baby has formed their nursing technique and is less likely to experience nipple teat confusion. It’s much easier to transition between breast and bottle when you supply is established, as teat preference is minimized at this age.

Returning to work

If you are exclusively breastfeeding and only expressing when returning to work, there is no need to express before you need to. We would recommend you start to practice with your pump a few weeks before you return to work, giving you time to iron out any issue you have. If you are renting a pump to express, it will keep the cost down as you don’t need to rent from birth.


Breast preference

Young babies tend to develop teat preference as the milk is easier to get to, yet older babies can develop a breast preference. This is caused by baby feeding more comforted by the skin to skin contact of breastfeeding. If you baby rejects a bottle its best to experiment with different teats as they may have a preference for the sturdy silicone kind or the softer latex type.