Table 3.
Maternal outcomes
| Nifedipine (n=298) | Labetalol (n=295) | Methyldopa (n=301) | Absolute difference, nifedipine vs labetalol (95% CI) | Absolute difference, nifedipine vs methyldopa (95% CI) | Absolute difference, labetalol vs methyldopa (95% CI) | ||
|---|---|---|---|---|---|---|---|
| Primary outcome* | |||||||
| Achieved primary outcome | 249 (84%) | 228 (77%) | 230 (76%) | 6·3 (−0·1 to 12·6) | 7·1 (0·8 to 13·5) | 0·9 (−5·9 to 7·6) | |
| Exploratory results of primary outcome | |||||||
| Achieved primary outcome without needing additional antihypertensive therapy† | 247 (83%) | 227 (77%) | 190 (63%) | 6·0 (−0·4 to 12·4) | 19·8 (12·9 to 26·7) | 13·8 (6·5 to 21·1) | |
| Reached the blood pressure target | 254 (85%) | 231 (78%) | 232 (77%) | 6·9 (0·7 to 13·1) | 8·2 (1·9 to 14·4) | 1·2 (−5·5 to 7·9) | |
| Any adverse outcome‡ | 7 (2%) | 4 (1%) | 3 (1%) | 1·0 (−1·2 to 3·2) | 1·4 (−0·7 to 3·4) | 0·4 (−1·4 to 2·1) | |
| Received additional antihypertensive drugs | 2 (1%) | 9 (3%) | 56 (19%) | −2·4 (−4·6 to −0·2) | −17·9 (−22·4 to −13·4) | −15·6 (−20·4 to −10·7) | |
| Achieved primary outcome at 3 h | 219 (74%) | 212 (72%) | 185 (62%) | 1·6 (−5·5 to 8·8) | 12·0 (4·6 to 19·5) | 10·4 (2·9 to 17·9) | |
| Received magnesium sulphate during study period | 31 (10%) | 40 (14%) | 34 (11%) | −3·2 (−8·4 to 2·1) | −0·9 (−5·9 to 4·1) | 2·3 (−3·0 to 7·6) | |
| Delivery outcomes | |||||||
| Mode of delivery (n=295 vs n=290 vs n=295) | |||||||
| Vaginal delivery | 104 (35%) | 104 (36%) | 116 (39%) | −0·6 (−8·4 to 7·2) | −4·0 (−11·8 to 3·8) | −3·4 (−11·2 to 4·4) | |
| Forceps delivery | 1 (<1%) | 0 | 0 | 0·3 (−0·3 to 0·9) | 0·3 (−0·3 to 0·9) | 0 (0 to 0) | |
| Caesarean section | 190 (64%) | 186 (64%) | 179 (61%) | 0·3 (−7·5 to 8·1) | 3·7 (−4·1 to 11·5) | 3·4 (−4·4 to 11·2) | |
| Indications for caesarean section (n=188 vs n=179 vs n=178)§ | |||||||
| Breech presentation | 1 (1%) | 0 | 2 (1%) | 0·5 (−0·5 to 1·5) | −0·6 (−2·4 to 1·2) | −1·1 (−2·6 to 0·4) | |
| Twins | 2 (1%) | 0 | 0 | 1·1 (−0·4 to 2·6) | 1·1 (−0·4 to 2·6) | 0 (0 to 0) | |
| Fetal heart rate abnormalities | 25 (13%) | 24 (13%) | 22 (12%) | −0·1 (−7·1 to 6·9) | 0·9 (−6·0 to 7·8) | 1·0 (−6·0 to 8·0) | |
| Other fetal indications | 3 (2%) | 3 (2%) | 4 (2%) | −0·1 (−2·7 to 2·5) | −0·6 (−3·4 to 2·2) | −0·5 (−3·4 to 2·4) | |
| Uncontrolled blood pressure | 4 (2%) | 13 (7%) | 10 (6%) | −5·2 (−9·5 to −0·9) | −3·5 (−7·5 to 0·5) | 1·7 (−3·4 to 6·8) | |
| Previous caesarean section | 24 (13%) | 27 (15%) | 21 (12%) | −2·3 (−9·4 to 4·8) | 1·0 (−5·7 to 7·7) | 3·3 (−3·8 to 10·4) | |
| Unfavourable cervix | 20 (11%) | 29 (16%) | 22 (12%) | −5·6 (−12·6 to 1·4) | −1·8 (−8·3 to 4·7) | 3·8 (−3·4 to 11·1) | |
| Failed induction of labour | 66 (35%) | 61 (34%) | 62 (35%) | 1·0 (−8·7 to 10·7) | 0·3 (−9·5 to 10·1) | −0·7 (−10·6 to 9·2) | |
| Failure to progress after 6-cm dilation | 14 (7%) | 5 (3%) | 7 (4%) | 4·6 (0·1 to 9·1) | 3·5 (−1·2 to 8·2) | −1·1 (−4·8 to 2·6) | |
| Other | 10 (5%) | 5 (3%) | 10 (6%) | 2·5 (−1·5 to 6·5) | −0·3 (−5·0 to 4·4) | −2·8 (−7·0 to 1·4) | |
| Median time from randomisation to delivery (IQR), h (n=295 vs n=290 vs n=295) | 24·5 (14·5–49·4) | 23·6 (14·3–44·7) | 22·8 (13·5–46·1) | 0·9 (−2·8 to 4·5) | 1·8 (−1·7 to 5·2) | 0·9 (−2·5 to 4·3) | |
| Adverse maternal outcomes¶ | |||||||
| Seizure | 0 | 1 (<1%) | 0 | −0·3 (−0·9 to 0·3) | 0 (0 to 0) | 0·3 (−0·3 to 0·9) | |
| Adverse CNS outcome (stroke or cortical blindness) | 0 | 0 | 0 | .. | .. | .. | |
| Pulmonary oedema (oxygen saturation <90% and abnormal chest x-ray) | 0 | 0 | 0 | .. | .. | .. | |
| Oliguria (<25 cm3/h for 2 h) up to 2 h after end of study period | 0 | 0 | 0 | .. | .. | .. | |
| Disseminated intravascular coagulation, diagnosed by treating physician | 0 | 0 | 0 | .. | .. | .. | |
| Admission to intensive care unit | 0 | 0 | 0 | .. | .. | .. | |
| Dialysis | 0 | 0 | 0 | .. | .. | .. | |
| Mechanical ventilation | 0 | 0 | 0 | .. | .. | .. | |
| Complications of labour and delivery | |||||||
| Placental abruption | 0 | 1 (<1%) | 0 | −0·3 (−0·9 to 0·3) | 0 (0 to 0) | 0·2 (−0·5 to 0·9) | |
| Post-partum haemorrhage | 2 (1%) | 1 (<1%) | 0 | 0·4 (−0·7 to 1·5) | 0·7 (−0·2 to 1·6) | 0·2 (−0·5 to 0·9) | |
| Received blood products after trial entry | 10 (3%) | 5 (2%) | 3 (1%) | 1·7 (−0·8 to 4·2) | 2·4 (0·1 to 4·7) | 0·7 (−1·2 to 2·6) | |
| Maternal death | 0 | 0 | 0 | 0 (0 to 0) | 0 (0 to 0) | 0 (0 to 0) | |
Data are n (%), unless otherwise indicated.
Defined as attaining the blood pressure target (120–150 mm Hg systolic and 70–100 mm Hg diastolic) after 6 h without an adverse outcome (systolic blood pressure <120 mm Hg, diastolic blood pressure <70 mm Hg, or both; fetal compromise; or caesarean section for fetal distress, severe headache, or eclampsia) during the study period.
During the 6-h study period or, if delivered during the study period, last blood pressure measurement before birth.
Included low blood pressure and fetal compromise (nifedipine, n=2; labetalol, n=0; methyldopa, n=0); caesarean section for fetal distress (nifedipine, n=3; labetalol, n=1; methyldopa, n=1); severe headache (defined as a pain score ≥5 on a 7-point visual analogue scale) during or up to 2 h after the end of the study period that resulted in a change in treatment (nifedipine, n=2; labetalol, n=2; methyldopa, n=2); or a seizure during or up to 2 h after the end of the study period (nifedipine, n=0; labetalol, n=1; methyldopa, n=0).
Women could have more than one indication.
Between study start and discharge, unless otherwise indicated.