Summary of findings 1. Probiotics compared to placebo for preventing mastitis after childbirth.
| Probiotics compared to placebo for preventing mastitis after childbirth | ||||||
| Patient or population: postpartum breastfeeding women Setting: obstetric outpatient clinic Intervention: probiotics Comparison: placebo | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with placebo | Risk with probiotics | |||||
| Incidence of mastitis within 6 months postpartum | Study population | RR 0.51 (0.35 to 0.75) | 399 (2 RCTs) | ⊕⊕⊝⊝ LOW 1 | ||
| 293 per 1000 | 149 per 1000 (102 to 220) | |||||
| Recurrence of mastitis within 12 months postpartum | Not reported | |||||
| Breast abscess within 6 months postpartum | Not reported | |||||
| Nipple damage within 6 months postpartum | Study population | RR 0.33 (0.11 to 1.01) |
424 (1 RCT) |
⊕⊝⊝⊝ VERY LOW 1 2 | ||
| 59 per 1000 | 19 per 1000 (6 to 59) |
|||||
| Duration of any breastfeeding | Not reported | |||||
| Breast pain | Study population | RR 0.81 (0.64 to 1.01) | 335 (2 RCTs) | ⊕⊕⊝⊝ LOW3 4 | ||
| 522 per 1000 | 423 per 1000 (334 to 527) | |||||
| Number of women with adverse events | In one trial no women in either the probiotics group or the placebo group experienced adverse events | 108 (1 RCT) | ⊕⊕⊝⊝ LOW 5 | |||
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: Confidence interval; RR: Risk ratio; OR: Odds ratio; | ||||||
| GRADE Working Group grades of evidence High certainty: We are very confident that the true effect lies close to that of the estimate of the effect Moderate certainty: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different Low certainty: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low certainty: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect | ||||||
1 Downgraded two levels due to risk of bias: unclear allocation concealment, high risk of reporting bias, and missing data
2 Downgraded one level for indirectness: measured as number of women using topical treatment for nipple cracks
3 Downgraded one level due to risk of bias: unclear allocation concealment and high risk of selective reporting
4 Downgraded one level for imprecision: 95% confidence interval is consistent with possible benefit and possible harm
5 Downgraded two levels for imprecision: few participants and no events