Summary of findings for the main comparison. Immersion in water compared to no immersion during first stage of labour in water during labour and birth.
| Immersion in water compared to no immersion during first stage of labour in water during labour and birth | ||||||
| Patient or population: women in labour Setting: hospital‐based maternity units in the following countries: UK, Canada, Iran, Finland, Australia, USA, Belgium, Brazil, Sweden, South Africa and China. Intervention: immersion in water in the first stage of labour Comparison: no immersion during first stage of labour | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with no immersion during first stage of labour | Risk with immersion in water | |||||
| Mode of birth (spontaneous vaginal birth) | Study population | RR 1.01 (0.97 to 1.04) | 2559 (6 RCTs) | ⊕⊕⊕⊝ MODERATE 1 | ||
| 822 per 1000 | 830 per 1000 (797 to 855) | |||||
| Mode of birth (instrumental vaginal birth) | Study population | RR 0.86 (0.70 to 1.05) | 2559 (6 RCTs) |
⊕⊕⊝⊝ LOW 1 2 | ||
| 138 per 1000 | 119 per 1000 (97 to 1.05) |
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| Mode of birth (caesarean section) | Study population | RR 1.27 (0.91 to 1.79) | 2652 (7 RCTs) |
⊕⊕⊝⊝ LOW 2 3 | ||
| 41 per 1000 | 52 per 1000 (38 to 74) |
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| Use of analgesia (regional) | Study population | RR 0.91 (0.83 to 0.99) | 2439 (5 RCTs) | ⊕⊕⊕⊝ MODERATE 1 | ||
| 429 per 1000 | 390 per 1000 (356 to 424) | |||||
| Perineal trauma (third‐ or fourth‐degree tears) | Study population | RR 1.36 (0.85 to 2.18) | 2341 (4 RCTs) | ⊕⊕⊕⊝ MODERATE 1 | ||
| 25 per 1000 | 33 per 1000 (21 to 54) | |||||
| Perinatal death | Study population | ‐ | ‐ | ‐ | No trial reported this outcome. | |
| see comment | see comment | |||||
| Admission to neonatal intensive care unit | Study population | Average RR 1.30 (0.42 to 3.97) | 1511 (2 RCTs) | ⊕⊕⊝⊝ LOW 2 4 | ||
| 58 per 1000 | 75 per 1000 (24 to 229) | |||||
| Neonatal infection | Study population | RR 2.00 (0.50 to 7.94) | 1295 (5 RCTs) | ⊕⊝⊝⊝ VERY LOW 1 5 | ||
| 5 per 1000 | 9 per 1000 (2 to 37) | |||||
| Estimated blood loss (mL) | The mean estimated blood loss with immersion was 265.5 mL | MD 14.33 mL lower without immersion (63.03 mL lower to 34.37 mL higher) | ‐ | 153 (2 RCTs) | ⊕⊝⊝⊝ VERY LOW 6 7 | |
| *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 | ||||||
| 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 All trials had design limitations: No trial was blinded, two trials did not randomise adequately, and three did not report all outcomes (‐1)
2 Wide confidence intervals that cross the line of no effect (‐1)
3 All trials had design limitations: No trial was blinded, two trials did not randomise adequately, one did not conceal allocation, and three did not report all outcomes (‐1)
4 Both trials have design limitations: Neither trial was blinded, one trial did not randomise adequately, and both did not report all outcomes (‐1)
5 Few events and wide confidence intervals crossing the line of no effect (‐2)
6 Both trials have design limitations: Neither trial was blinded, one trial did not randomise adequately (‐1)
7 Small sample size and wide confidence intervals crossing the line of no effect (‐2)