Table 1. Summary of the characteristics of the included studies.
| First author[ref.] and year | Participant characteristics | Sample size (N) | Age (years) | Probiotic strain | Doses and administration pattern | Period of invention (weeks) | *Outcome indicators |
|---|---|---|---|---|---|---|---|
| EG/CG | EG/CG | ||||||
| Jiménez et al. 2008 | Milk bacterial count >4 log10 CFU/mL, and milk leukocyte count >6 log10 cells/mL; Mammary abscess or any other mammary pathology was excluded | 10/10 | NR | Lactobacillus salivarius CECT5713 and Lactobacillus gasseri CECT5714 | 1×1010CFU/day | ~4 | 3,6 |
| Arroyo et al. 2010 | 124(A group) 127(B group) /101(C group) |
NR | Lactobacillus fermentum CECT 5716/Lactobacillus salivarius CECT5713 | 1×109CFU/day | 3 | 2,3,4,6 | |
| Maldonado-Lobón et al. 2015 | milk bacterial count >3 log10 CFU/mL.; Mammary abscess or any other mammary pathology was excluded | 23(EG I) 24(EG II) 24(EG III) 27(CG) |
33.3±5.2 34.3±4.3 36.0±2.8 33.4±4.5 |
Lactobacillus fermentum CECT 5716 | 3×109(EG)CFU/day 6×109(EGI)CFU/day 9×109(EGII)CFU/day |
3 | 2,3,4,5 |
| Fernández et al. 2016 | Healthy pregnant women who had not taken probiotic supplements or received antibiotic treatment in the past 30 days | 55/53 | 31.18(±0.48)/30.51(±0.49) | Lactobacillus salivarius PS2 | 1×109CFU/day | ~8 | 1,2,3,6 |
| Hurtado et al. 2017 | Healthy pregnant women who have received prophylactic antibiotics 48 hours before and after delivery | 139/152 | 31.91(±0.49)/32.19(±0.48) | Lactobacillus fermentum | 3×109CFU/day | 16 | 1,2,3,5 |
| Jiménez et al. 2021 | Healthy pregnant women ≥18 years of age and with the intention to breastfeed | 165/163 | 33.00(±3.00)/33.00(±3.00) | Lactobacillus salivarius PS2 | 1×109CFU/day | from the 35th week of pregnancy until week 12 after delivery | 1,2,4 |
N: the number of subjects; EG: experimental group; CG: control group; NR: not reported; N: cannot be detected
*Outcome indicators: 1 = incidence of mastitis; 2 = breast pain; 3 = bacteria count in milk samples; 4 = adverse reaction; 5 = immune parameters in breast milk; 6 = detection of the lactobacillus strains in milk samples