Breastfeeding while pregnant: is it safe?

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Sophie has just found out she's pregnant, and she's excited but anxious. You see, she's still breastfeeding her 14-month-old, Mia, and she isn't ready to wean. She's concerned about how breastfeeding will affect her pregnancy and her unborn baby.  

Although Mia isn't breastfeeding a lot in comparison to a younger baby, Sophie knows it's still important for Mia's immunity, nutrition, and, above all, comfort. A few minutes at the breast is an easy 'pick me up' (literally) for Mia when she falls over or falls apart emotionally. It's also a great soother as she is cutting her molars.   

Sophie had planned to breastfeed Mia for at least two years, as recommended by The World Health Organization, knowing that this isn't just a recommendation for women in deprived circumstances: in one study of infants from 12 to 23 months (Dewey 2001) the author concluded, "Breast milk continues to provide substantial amounts of key nutrients well beyond the first year of life, especially protein, fat, and most vitamins."

How breastfeeding affects your unborn baby

For mothers like Sophie, concerns about breastfeeding while pregnant tend to focus on whether breastfeeding their current baby or toddler will deprive their unborn baby of nutrients. This can be even more of a concern if you fall pregnant while breastfeeding a younger baby - as happened to Jacqui. Jacqui's baby, Luke, is only six months old and has just started tasting family foods, so breastmilk is still an important part of Luke's diet.

Whatever the age of your current baby or the extent of his breastfeeding, your unborn baby will have first dibs on all the nutrients it needs. But because of your hormones, your milk supply is likely to reduce while pregnant. If you're breastfeeding a younger baby when you fall pregnant, you may find that with more frequent feeds and healthy nutrition, you can maintain an adequate milk supply.

If your milk supply reduces substantially, you may need to supplement.  With a toddler, you'll need to offer more foods and drink to make up for the reduced breastfeeding. Although you may be advised to boost your supply with herbs, this isn't safe; for instance, fenugreek, a herb that's often suggested to boost milk supply, is a uterine stimulant so should be avoided during pregnancy.  However, you can eat foods that have natural galactagogue effects, such as oats, and lactation cookies that are herb-free (see

Women often ask me "If I breastfeed up to the birth, will my newborn be deprived of colostrum?" Again, you can relax: your body knows exactly how to provide for your newborn. Your post-birth hormones will release colostrum so your baby will get this precious first immune boost. And even during pregnancy you can produce colostrum, as well as mature milk.

How it can affects your pregnancy


Another concern women have when breastfeeding during pregnancy is whether breastfeeding can cause miscarriage or premature labour. In short: you don't have to worry.

Nipple stimulation releases oxytocin and signals your breasts to eject milk, and can also make the uterine tissue contract (this reduces postpartum bleeding). But there's no evidence that this poses risks to your pregnancy.  This is because, during pregnancy, less oxytocin is released in response to nipple stimulation. As well as that, the 'oxytocin receptor sites', the uterine cells that notice the hormones and cause contractions, are low in numbers up until 38 weeks - they build up gradually after that time, then boosting significantly as labour begins. This means that until your pregnancy is at or near term, your uterus is in protective mode, supporting your unborn baby.  

Of course, if you have a high risk pregnancy or you are concerned about breastfeeding affecting your pregnancy, it is important to discuss this with your health care providers.  

How it can affect you

Breastfeeding during pregnancy means you are nourishing two babies, which places extra demands on your own body for nutrients and energy. It's important to take extra care of yourself at this time.

Some women report their morning sickness as being worse, although for others, it's not an issue. As well as changing hormones, nausea can be due to hunger, thirst and tiredness, so try to eat small amounts frequently, drink to your thirst, and rest as much as possible.  

The natural nipple tenderness of pregnancy can make breastfeeding painful in the early weeks, so pay close attention to how your baby or toddler is attaching.

It's also natural to have feelings of aversion while breastfeeding your toddler, especially if breastfeeding is painful. With a toddler, you can shorten breastfeeds by telling your toddler, "We'll count to ten, then you can have a cup of water/we'll play with the ball/go to the park" - that is, you can create a diversion.

To wean or not to wean

Many women happily breastfeed well into pregnancy while others wean sooner; yet others continue to breastfeed both infants together. This is a personal choice that depends on your own health, energy and resources as well as how breastfeeding works for you and your child.  

During one of my own pregnancies, my toddler nursed less and less frequently. My pregnancy hormones affected my supply so that one day, he simply smiled and told me, "No more milk."  This same toddler asked to breastfeed along with the new baby, but as he sucked he got a mouthful of milk from a strong 'let-down' . He screwed up his face and said, "Uck! Baby can have that."

When pregnant with another baby, my child decided "The baby can have that side." The side she continued to nurse off produced mature milk, and the side she stopped feeding from dried up then started producing colostrum – completely independent of each other. I continued to breastfeed through pregnancy then tandem nursed my daughters.

Of course this isn't everyone's cup of tea, and I won't pretend it was easy. Although there were lovely moments when they held each other's hands as they drank, there were times when I felt completely overwhelmed, as though I was a piece of meat being grappled by two little puppies. For my girls though, nursing together was a beautiful bonding time. It helped eliminate sibling resentment, and even as adults, they are the best of friends.

Whatever you choose – to wean or not to wean – remember the mantra, 'gradually with love.' You don't have to make a decision with any urgency, and it will be much easier for you and your little one if there's no pressure around ending this precious relationship.  

Pinky McKay is an internationally certified lactation consultant and best selling baby care author of Sleeping Like a Baby and Parenting by Heart. She is also the creator of Boobie Bikkies, all natural and organic cookies to boost  breastfeeding mothers energy and support a healthy milk supply. Download Pinky's free ebook Making More Mummy Milk, Naturally at