Table 4.
Adverse effect estimates from comparative studies with concurrent controls
| Study | Participants and comparison | Adverse effect | Estimates | P-value or effect estimate (95% CI) |
|---|---|---|---|---|
|
Magnesium sulphate versus no magnesium sulphate | ||||
| Ales 1987 [37] |
178 women. MgSO4 for H (n = 64) v no MgSO4 (n = 114) |
Caesarean |
39.1 v 29.0% |
AOR 2.81 (1.99, 3.62)^ |
| |
|
Caesarean (failure to progress) |
72.0% v 42.4% |
OR 3.49 (1.15, 10.62) |
| Seyb 1999 [38] |
1561 women. MgSO4 for PE (n = 54) v no MgSO4 (n = 1507) |
Caesarean |
22.2% v 10.2% |
OR 2.53 (1.30, 4.91) |
| |
|
Caesarean |
|
AOR 2.18 (1.04, 4.55)* |
| Park 2006 [39] |
231 women. MgSO4 for PE (n = 29) v no MgSO4 (n = 202) |
Failed induction of labour |
|
AOR 17.78 (1.62, 195.14)~ |
| Assaley 1998 [40] |
18 women. MgSO4 for PE (n = 15) v no MgSO4 (n = 3) |
Significant ↑ in bleeding time with MgSO4 (v no significant change with no MgSO4) |
P < 0.0043 |
|
| Kynczl-Leisure 1996 [41] |
12 women. MgSO4 for PE (n = 9) v no MgSO4 (n = 3) |
Significant ↑ in bleeding time with MgSO4 (v no significant change with no MgSO4) |
P < 0.01 |
|
| Ramanathan 1988 [42] |
16 women. MgSO4 for PE (n = 10) v no MgSO4 (n = 6) |
Significant ↓ in pulmonary function (FVC (L), FEV1(L), MVV (L)) with MgSO4 (v no significant change with no MgSO4) |
P < 0.005; P < 0.01; P < 0.02 |
|
| Ramanathan 1988 [43] |
32 women. 1. Labour augmentation and MgSO4 for PE (n = 16) v 2. MgSO4 postpartum for PE (n = 6) v 3. Labour induction and no MgSO4 (n = 10) |
Depression of neuromuscular transmission for Groups 1 and 2 (before MgSO4 to during MgSO4) v no changed for Group 3 (before and during induction, and postpartum) |
||
| Poggi 2003 [44] |
66 women. Pulmonary oedema (n = 15) v no pulmonary oedema (n = 51) |
Case (pulmonary oedema) v control MgSO4 exposure (for PE or PTL) |
93.3% v 62.7% |
P = 0.049 |
|
All women received magnesium sulphate: comparison based on antihypertensive agent received | ||||
| Magee 2005 [45] |
377 women who all received MgSO4 for PE. 1. Nifedipine (n = 162) v 2. Other antihypertensive (n = 32) v 3. No antihypertensive (n = 183) |
Calcium gluconate given |
0.5% v 3.1% v 0.0% |
P = 0.30 (1v2); P = 0.47 (1v3) |
| |
|
Infusion stopped due to adverse effects |
1.2% v 3.1% v 4.9% |
P = 0.42 (1v2); P = 0.05 (1v3) |
| |
|
Infusion reduced due to adverse effects |
8.0% v 3.1% v 7.7% |
P = 0.47 (1v2); P = 0.90 (1v3) |
| |
|
Neuromuscular weakness |
53.1% v 53.1% v 44.8% |
P = 0.99 (1v2); P = 0.13 (1v3) |
| |
|
Absent deep tendon reflexes |
5.6% v 6.3% v 3.8% |
P = 0.12 (1v2); P = 0.22 (1v3) |
| |
|
Weakness |
15.4% v 28.1% v 10.9% |
P = 0.99 (1v2); P = 0.26 (1v3) |
| |
|
Respiratory depression |
9.9% v 9.4% v 6.6% |
P = 0.99 (1v2); P = 0.45 (1v3) |
| |
|
Neuromuscular blockade |
0.0% v 6.25% v 0.0% |
P = 0.03 (1v2); P = NA (1v3) |
| |
|
Maternal hypotension |
41.4% v 31.3% v 53.0% |
P = 0.33 (1v2); P = 0.04 (1v3) |
| |
|
Nausea/vomiting |
49.4% v 43.8% v 47.0% |
P = 0.70 (1v2); P = 0.66 (1v3) |
| |
|
Drowsiness/confusion |
45.7% v 37.5% v 38.3% |
P = 0.44 (1v2); P = 0.16 (1v3) |
| |
|
Dizziness |
28.4% v 25.0% v 20.8% |
P = 0.83 (1v2); P = 0.10 (1v3) |
| |
|
Flushing |
22.2% v 15.6% v 20.8% |
P = 0.48 (1v2); P = 0.74 (1v3) |
| |
|
Thirst |
20.4% v 21.9% v 7.1% |
P = 0.81 (1v2); P < 0.001 (1v3) |
| |
|
Respiratory problems |
14.8% v 6.3% v 7.7% |
P = 0.26 (1v2); P = 0.03 (1v3) |
| |
|
Dyspnoea |
8.6% v 0.0% v 4.9% |
P = 0.13 (1v2); P = 0.17 (1v3) |
| |
|
Pulmonary oedema |
2.5% v 0.0% v 1.1% |
P = 0.99 (1v2); P = 0.57 (1v3) |
| |
|
Oxygen required |
4.9% v 3.1% v 2.2% |
P = 0.99 (1v2); P = 0.16 (1v3) |
| |
|
Maternal tachycardia |
22.2% v 18.8% v 14.2% |
P = 0.82 (1v2); P = 0.05 (1v3) |
| |
|
Itchy/tingling |
14.8% v 18.8% v 15.3% |
P = 0.60 (1v2); P = 0.90 (1v3) |
| |
|
Tremulous |
6.8% v 9.4% v 2.7% |
P = 0.27 (1v3) |
| |
|
Minor bleeding |
4.9% v 6.3% v 0.0% |
P = 0.67 (1v2); P = 0.002 (1v3) |
| Chest pain | 5.6% v 6.3% v 2.7% | P = 0.99 (1v2); P = 0.19 (1v3) | ||
The bold effect estimates indicate statistical significance. ^Logistic regression was used to adjust for age, race, parity, physician status, obesity, gestational age, and mean arterial pressure during labour; * “Controlling for the significant confounding variables”; ~ “logistic regression analyses…adjusting for the potential confounding variables”.
Abbreviations: AOR adjusted odds ratio, CI confidence interval, FEV1 forced expiratory volume at 1 second, FVC forced vital capacity, H hypertension, MgSO4 magnesium sulphate, MVV maximum voluntary ventilation, NA not applicable, OR odds ratio, PE pre-eclampsia, PTL: preterm labour, v: versus, ↑: increase, ↓: decrease.