Table 4. Outcomes for Pregnant Individuals During the Birth Hospitalizationa.
| No./total (%) | Risk difference (95% CI), % | Relative risk (95% CI) | P valueb | |||
|---|---|---|---|---|---|---|
| Magnesium sulfate | Placebo | Unadjusted | Adjustedb | |||
| Adverse events because of the infusion | ||||||
| Any | 531/690 (77) | 136/667 (20) | 56.57 (52.18 to 60.95) | 3.77 (3.23 to 4.41) | 3.76 (3.22 to 4.39) | <.001 |
| Nausea | 108/690 (16) | 36/667 (5.4) | 10.25 (7.05 to 13.46) | 2.90 (2.02 to 4.16) | 2.90 (2.02 to 4.16) | <.001 |
| Vomiting | 36/690 (5.2) | 15/667 (2.3) | 2.97 (0.96 to 4.97) | 2.32 (1.28 to 4.20) | 2.31 (1.28 to 4.15) | .01 |
| Flushing | 400/690 (58) | 55/667 (8.3) | 49.73 (45.49 to 53.96) | 7.03 (5.42 to 9.13) | 6.96 (5.36 to 9.03) | <.001 |
| Arm discomfort | 275/690 (40) | 24/667 (3.6) | 36.26 (32.34 to 40.17) | 11.1 (7.4 to 16.6) | 11.1 (7.4 to 16.6) | <.001 |
| Dry mouth | 125/690 (18) | 23/667 (3.5) | 14.67 (11.48 to 17.86) | 5.25 (3.41 to 8.09) | 5.18 (3.37 to 7.97) | <.001 |
| Sweating | 87/690 (13) | 15/667 (2.3) | 9.48 (6.77 to 12.19) | 5.61 (3.28 to 9.60) | 5.42 (3.17 to 9.26) | <.001 |
| Dizziness | 83/690 (12) | 17/667 (2.6) | 3.90 (2.29 to 5.50) | 4.72 (2.83 to 7.87) | 4.71 (2.83 to 7.84) | <.001 |
| Blurred vision | 30/690 (4.4) | 3/667 (0.5) | 10.36 (7.64 to 13.08) | NE | NE | <.001c |
| Respiratory rated | 5/690 (0.7) | 3/667 (0.5) | 0.27 (−0.54 to 1.09) | NE | NE | .73c |
| Blood pressuree | 42/690 (6.1) | 18/667 (2.7) | 3.39 (1.22 to 5.56) | 2.26 (1.31 to 3.88) | 2.20 (1.28 to 3.77) | .004 |
| Discontinued infusion because of adverse events | 20/690 (2.9) | 1/667 (0.2) | 2.75 (1.46 to 4.03) | NE | NE | <.001c |
| Postpartum hemorrhage | ||||||
| Any (≥500 mL) | 170/729 (23) | 167/704 (24) | −0.40 (−4.79 to 3.99) | 0.98 (0.82 to 1.18) | 0.98 (0.81 to 1.17) | .80 |
| Major (≥1000 mL) | 25/729 (3.4) | 12/704 (1.7) | 1.72 (0.09 to 3.36) | 2.01 (1.02 to 3.97) | 1.98 (1.01 to 3.91) | .05 |
| Blood transfusion given | 24/729 (3.3) | 16/704 (2.3) | 1.02 (−0.68 to 2.72) | 1.45 (0.78 to 2.70) | 1.46 (0.78 to 2.72) | .23 |
| Cesarean delivery | 406/729 (56) | 427/704 (61) | −4.96 (−10.06 to 0.14) | 0.92 (0.84 to 1.00) | 0.91 (0.84 to 0.99) | .03 |
| Elective | 140/729 (19) | 135/704 (19) | 0.03 (−4.05 to 4.11) | 1.00 (0.81 to 1.24) | 1.00 (0.81 to 1.22) | .96 |
| Emergency | 256/729 (35) | 284/704 (40) | −5.22 (−10.24 to −0.21) | 0.87 (0.76 to 0.99) | 0.86 (0.76 to 0.98) | .03 |
| Reason for cesarean delivery | ||||||
| Abnormal lie | 97/729 (13) | 105/704 (15) | ||||
| Fetal compromise | 91/729 (13) | 100/704 (14) | ||||
| Hemorrhage | 76/729 (10) | 62/704 (8.8) | ||||
| Twin pregnancy | 58/729 (8.0) | 68/704 (9.7) | ||||
| Previous cesarean delivery | 53/729 (7.3) | 54/704 (7.7) | ||||
Abbreviation: NE, not estimable.
a
There were no cases of serious cardiovascular or respiratory adverse events (eg, death of pregnant individual, cardiac arrest, or respiratory arrest).
b
Adjusted for hospital site, gestational age at entry, and plurality.
c
Calculated using the Fisher exact test.
d
Decreased to greater than 4 breaths/min below baseline or decreased to less than 12 breaths/min.
e
Decreased to greater than 15 mm Hg below baseline level.