Table 3 Impact of anti-hypertensive drugs to treat chronic maternal hypertension on stillbirth and perinatal mortality

Abalos et al. 2007 [29]

Brazil, Caribbean Islands, Ireland, Israel, Italy, South Africa, Sweden, UK, USA, Sudan, Argentina, Australia, France, India, Venezuela.

Meta-analysis (Cochrane). 43 RCTs included.

To assess the effects of anti-hypertensive drug treatments for women with mild to moderate hypertension during pregnancy on pregnancy outcomes.

SBR: RR = 1.14 (95% CI: 0.60, 2.17) [NS]

PMR: RR = 0.96 (95% CI: 0.60–1.54) [NS]

Duley et al. 2006 [21]

UK (Northern Ireland, England), South Africa, USA, Brazil, The Netherlands, Germany, Australia.

Meta-analysis (Cochrane). 13 RCTs included.

To compare the impact of different anti-hypertensive drugs for very high blood pressure during pregnancy on pregnancy outcomes.

PMR: RR = 0.50 (95% CI: 0.05–4.94) [NS] in labetalol vs. hydralazine groups, respectively.

PMR: RR = 1.36 (95% CI: 0.42–4.41) [NS] in calcium channel blockers vs. hydralazine groups, respectively.

King et al. 2003 [36]

USA, Spain, France, Israel, The Netherlands, Thailand.

Meta-analysis. 10 RCTs included (N = 810 participants).

To assess the effects on maternal, fetal and neonatal outcomes of calcium channel blockers, administered as a tocolytic agent, to women in pre-term labour.

PMR: RR = 1.65 (95% CI: 0.74–3.64).

Magee and Duley 2003 [35]

England, Caribbean Islands, Israel, France, Scotland, Sweden, USA, Argentina, Australia, India, Venezuela.

Meta-analysis (Cochrane). 27 RCTs included.

To assess whether oral beta-blockers are better than placebo, or no beta-blocker, and have advantages over other anti-hypertensives, for women with mild to moderate pregnancy hypertension.

PMR: RR = 1.01 (95% CI: 0.46–2.22) [NS] in beta-blocker vs. placebo/no beta-blocker groups, respectively.

Meher et al. 2007 [41]

Italy.

Meta-analysis. 4 RCTs included.

Compared the impact of nitric oxide vs. placebo/no intervention in treatment of hypertension in pregnancy.

PMR + NMR: RR = 0.25 (95% CI: 0.03–2.34) [NS]

[0/65 vs. 2/49 in the nitric oxide group vs. the placebo group, respectively.]

Say et al. 1996 [37]

The Netherlands.

1 RCT included (N = 100 participants).

Assessed the effects of calcium channel blockers on fetal growth and neonatal morbidity and mortality in pregnancies where impaired fetal growth was suspected.

PMR: OR = 0.14 (95% CI: 0.00–6.82).

Intervention studies

Hennessy et al. 2007 [40]

Australia, Sydney, tertiary referral maternity hospital.

RCT. N = 124 hypertensive women.

Compared the impact of IV hydralazine (5 mg doses) to mini-bolus diazoxide (15 mg doses) on pregnancy outcomes.

PMR: 3 vs. 1 perinatal deaths in hydralazine vs. diazoxide groups, respectively. No statistical significance data given.

Observational studies

Kanner et al. 1980 [189]

Israel, Tel Aviv University Medical School.

Prospective cohort study. N = 13 patients with longstanding hypertension during 15 pregnancies.

Measured pregnancy outcomes after administering a combination of propranolol and hydralazine to subjects with essential hypertension in pregnancy.

SB: 1/15 in subjects given propranolol+hydralazine. No controls.