Safety of Probiotics During Pregnancy

General Safety Profile

Most probiotics in commercial use are derived from fermented foods with a long history of safe consumption or from microbes that naturally colonize humans 1
The European Food Safety Authority (EFSA) and the U.S. Food and Drug Administration (FDA) consider common probiotic species safe for the general population 1
The overwhelming existing evidence suggests that probiotics are safe for healthy individuals, including pregnant women 1

Serious adverse effects from probiotics are rare but have been documented in vulnerable populations 1
High-risk groups requiring careful evaluation before probiotic use include patients with damaged intestinal mucosa 1, immunocompromised individuals 1, 2, patients with central venous catheters 2, those with cardiac valvular disease 2, and patients with short-gut syndrome 2

Specific strains like Lactobacillus rhamnosus (now reclassified as Lacticaseibacillus rhamnosus) have been well-studied and have a good safety profile 2
Saccharomyces boulardii should be used with caution as it has been associated with fungemia in critically ill and immunocompromised patients 1

Always check the precise identity of the bacteria at the strain level when selecting a probiotic 3
Be aware that probiotic quality varies - the amount of dead bacteria in a preparation is inversely proportional to the product quality 1, 4
Consider products that have been deposited at a biodepository such as the American Type Culture Collection (ATCC) for quality assurance 3
Exercise caution with products containing extremely high concentrations of bacteria (450-900 billion bacteria per dose) 1

The administration of probiotics to pregnant mothers and postnatally to children reduces the risk of atopy (RR 0.71, 95% CI 0.57-0.89) and food hypersensitivity (RR 0.77, 95% CI 0.61-0.98), as recommended by the European Food Safety Authority and supported by the World Health Organization guidelines 5

Serious adverse effects from probiotics are rare but have been documented in vulnerable populations, including cases of bacterial sepsis linked to lactobacilli supplements and death from gastrointestinal mucormycosis in a preterm infant from mold contamination, highlighting the need for caution as advised by the American College of Gastroenterology 6
The American College of Gastroenterology recommends exercising caution with probiotic products containing extremely high concentrations of bacteria (450-900 billion bacteria per dose), as safety becomes more sensitive with these formulations 6
The American Gastroenterological Association advises against using probiotics in patients with predicted severe acute pancreatitis, as treatment with multispecies probiotic preparations has been associated with increased mortality risk in this specific population 6
The European Society for Pediatric Gastroenterology, Hepatology and Nutrition recommends choosing well-studied strains like Lactobacillus rhamnosus, which have been extensively studied and have good safety profiles, and always verifying the precise bacterial identity at the strain level when selecting a probiotic 6

The American Gastroenterological Association (AGA) recommends combinations including Lactobacillus rhamnosus with Bifidobacterium species, or Lactobacillus acidophilus with Bifidobacterium species for preterm, low-birth-weight infants 7