Pregnancy The Science of Nutrition

A Complete Guide to Probiotics During Pregnancy

Hillary Bennetts

A Complete Guide to Probiotics During Pregnancy

Table of contents

  • Intro
  • What Is the Microbiome?
  • Your Microbiome in Pregnancy
  • How Does a Baby’s Microbiome Develop?
  • Why Gut Health Matters For Baby
  • Is Any Probiotic Effective?
  • The Bottom Line

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Gut health can be complicated and the conversation around it can be noisy. Needed exists not just to create better nutrition products, but to empower mamas with information. In that spirit, we wrote this blog post to answer some of the common questions we get from our community of mamas and dive deep into why we created our Pre/Probiotic. Caring for your microbiome can have a profound impact on your own health and your baby’s health, now and for years to come. 

What is the microbiome? 

The microbiome is the collection of bacteria that live within and on our bodies. While this balance of bacteria is often thought to reside only within the gut, or large intestine, the reality is that your microbiome extends far beyond the digestive tract and throughout your body, colonizing everything from your skin to your vagina. 

While the amount and type of good and bad bacteria are in a constant state of flux depending on what you eat and other lifestyle factors like stress, antibiotic use, and toxin exposure, the trillions of bacteria in your microbiome generally outnumber human cells in your body 10 to 1! 

Your microbiome has a tremendous impact on your health, influencing a variety of systems:

  • Digestion: how you digest and absorb nutrients from the food that you eat. 
  • Immune response: this includes not only how your body defends and protects itself from external factors that lead to acute illness (we know that a large portion, up to 80%, of our immune systems are located in the gut) but also how it responds to its own stressors. The latter can impact your risk for autoimmune conditions in which your body sees its own healthy tissues as foreign invaders and attacks them. 
  • Emotional health: how your gut and brain interaction can impact stress, mood, anxiety, and more.
  • Skin: the influence of the gut microbiome extends to influence even seemingly distant organ systems, including the skin. Probiotics and prebiotics have proven beneficial in the prevention and/or treatment of inflammatory skin conditions like acne, atopic dematitis, and psoriasis. Mama’s skin microbiome can affect baby’s as well, especially during skin-to-skin interaction. 

Your microbiome in pregnancy

The impact of your microbiome on health extends to pregnancy, too. A healthy microbiome influences a variety of factors for both mama and baby and can impact risk of pregnancy complications. 

A woman with gut dysbiosis, or with a microbiome that is imbalanced in its ratio of healthy to unhealthy bacteria, can have increased risk of preterm birth, preeclampsia, gestational diabetes, and excessive weight gain during pregnancy. 

Research has also suggested that supplementation with targeted probiotics during pregnancy can result in improved blood sugar levels. Blood sugar levels can impact so many aspects of pregnancy, such as nausea, energy, and mood, but one study concluded that supplementation with probiotics during pregnancy also reduced the risk of gestational diabetes by up to 23%. And the benefits of probiotics during pregnancy aren’t lost if you’ve already been diagnosed with gestational diabetes, as probiotic supplementation has been shown to reduce the risk of having a larger-than-gestational-age baby in women with gestational diabetes.

The vagina is a key component of your microbiome throughout your life, but it is an especially fundamental piece of your health and your baby’s health during pregnancy. The vaginal microbiome shifts and changes along with your hormones to adapt to your life stage, beginning with your first period and extending all the way through menopause. During pregnancy, as hormones increase and signal that the body is pregnant, the vagina populates with more Lactobacillus to protect against infections that could be harmful to you or baby. For example, an abundance of lactic-acid producing bacteria like Lactobacillus make it more difficult for certain other harmful bacteria to exist. This can help prevent common infections like bacterial vaginosis.  

How does a baby’s microbiome develop? 

It used to be thought that an infant developed in-utero with a sterile gut and was only first established with bacteria (“seeded”) during delivery, but recent research has challenged this idea. We now know that there are three main ways that mama helps to seed baby’s microbiome:

  • Interaction in utero: recent research has found bacteria in the placenta, amniotic fluid, and first-pass meconium, suggesting that baby begins to be seeded during pregnancy. Studies have also shown that babies who are exposed to antibiotics through mama during the second and third trimester are at significantly higher risk of obesity in childhood, a sign that baby’s microbiome is impacted by antibiotic use.
  • During birth: if born vaginally, baby is seeded with bacteria while passing through the vaginal cavity. This process is so beneficial that some who undergo C-section or require antibiotics during labor choose to swab mamas vagina followed by baby’s face and skin to help seed baby with some of this important bacteria.
  • After birth: skin-to-skin contact and and breastfeeding both continue supporting a healthy microbiome after birth
    • Breastfeeding is incredibly nourishing in its own right, but especially so when considering its role in shaping baby's microbiome. Recent studies have found that babies who are breastfed have a substantially higher abundance of beneficial Bifidobacteria from mama in their gut microbiome. As another example of how nature perfectly designed breastmilk for babies, the oligosaccharides (special sugars) found in mama’s breast milk act as prebiotics, or food, for the Bifidobacterium. 
    • Skin-to-skin contact has also been shown to support seeding of the microbiome. As one example, research shows that the Bifidobacteria in babies who received milk directly from mama’s breast was found to be higher than the Bifidobacteria in babies who received pumped breast milk, suggesting that some of the microbiome benefits of breastfeeding may lie in the skin-to-skin contact. Even if not breastfeeding, or exclusively breastfeeding, know that you can support  baby’s developing microbiome through the skin microbiome with direct contact. 

This is important and empowering information for mamas, as we can control what’s in our microbiome (and what’s passed along to baby) before, during, and after pregnancy. And since life doesn’t always go as planned, it provides us several ways to support the microbiome when certain circumstances are outside our control, like an unplanned C-section or antibiotics to fight a threatening infection.

Why gut health matters for baby

Does gut health really matter at such a young age? Absolutely. We have tremendous influence to help seed and support baby’s microbiome in such a way that will impact her health. Introducing these helpful bacteria to baby’s microbiome helps to establish a strong immune response early on. Research has shown that supporting the microbiome through supplementing with probiotics during pregnancy and breastfeeding can also help prevent allergies, eczema, asthma, and colic.

But the benefits extend far beyond infancy. The microbiome is critical for lifelong health and immunity and the diversity of mama’s microbiome helps to determine baby’s health outcomes, even into adulthood. 

Is any probiotic effective? 

With so many different brands and strains of probiotics, it can be a bit overwhelming to determine what you need for the important phases of mamahood. We thought so too, which is why we did the work for you. We started from scratch and worked with leading microbiome researchers and scientists to build a probiotic specific to the needs of mama and baby.

How did we do it? We started with targeted research around specific strains that benefit mama and baby. In some cases, the strains were commercially available, and for others, we dug in further to understand the mechanism of actions of each strain so that we could replace the unattainable strains with something tangible and effective. For example, in the case of a strain to prevent Group B Strep, the specific strains studied aren't commercially available. So instead, we looked to accomplish what that strain does to increase effectiveness - increase acidity of the gut. So we added in a variety of Lactobacilli strains that help to increase the acidity of the gut, plus Bacillus coagulans which impacts the vaginal microbiome, and Bacillus spores, which are extremely strong competitors to pathogens like Group B Strep.  With that in mind, here are the hand-picked strains included in our Pre/Probiotic:

3 Spore-based strains

  • MegaTrio™: a blend of Bacillus clausii SC-109, Bacillus subtilis HU58, and Bacillus coagulans SC-208 that supports healthy digestion, immunity, inflammatory responses, gut motility, improved Vitamin B status, and more. This trio also helps to produce lactic acid which increase the acidity of the gut and vagina to help crowd out bad bacteria that may lead to unwanted pregnancy outcomes.

3 Lactobacillus strains

  • Lactobacillus rhamnosus HN001: supplementation with this strain during the third trimester and breastfeeding was shown to significantly decrease the incidence of eczema in infants. 
  • Lactobacillus acidophilus La-14: this strain has been shown to have numerous benefits to both mama and baby by boosting immune function and also reducing anxiety and depression in pregnant and postpartum women. It also helps to protect the vaginal microbiome.
  • Lactobacillus reuteri 1E1: this strain is a lactic acid-producing bacteria that promotes bowel regularity, improves immune function, and may help reduce allergic eczema. Research has shown that supplementation with L. Reuteri during the third trimester significantly reduced incidence of allergies in childhood. This strain has also been associated with reduced Group B strep colonization in pregnant women.

1 Bifidobacterium strain

  • Bifidobacterium longum: a keystone species supporting optimal gut health, healthy digestion, and immune response. Our strain of Bifidobacterium longum BI-05 is well-studied for gut health and immunity in mama and baby, and for reducing allergic symptoms in baby.

2 Prebiotics

    • MicrobiomeX®: this is a natural citrus extract rich in polyphenols that supports digestive health and immunity by increasing microbial diversity in the gut and improving gut barrier function. It also helps to reduce inflammation and modulate damaging substances like lipopolysaccharides (LPS). A recent study found that women with recurrent pregnancy loss have a higher prevalence of intestinal barrier dysfunction and significantly increased levels of LPS in the bloodstream, so this inclusion is key to supporting healthy gestation.
    • Livaux™ FOS: this is a prebiotic, or food for the friendly probiotics. It is sourced from New Zealand gold kiwifruit and has the unique ability to support a healthy gut barrier without feeding unwanted harmful bacteria.

The bottom line

The health of mama’s gut influences the health of baby’s gut, and mama’s gut must be healthy, diverse, and balanced to help set baby up for success. Probiotics for mama are an effective and easy way to support both mama and baby before, during, and after pregnancy, but not all probiotics are created equally to include the specific strains that benefit baby. 

Look for the specific strains we’ve listed (e.g., Lactobacillus rhamnosus HN001) to ensure that you are taking the right probiotic for you and your baby or check out ours that has been uniquely and carefully developed to support mama and baby during the important stages of pregnancy and postpartum.

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Hillary Bennetts, Nutritionist

Hillary Bennetts is a nutritionist and business consultant focusing on prenatal and postpartum health. In addition to nutrition consulting, she provides business consulting and content creation for companies in the health and wellness industry. Hillary spent almost a decade in corporate consulting before shifting gears to combine her lifelong passion for health and wellness with her business background and nutrition education.