Improvement in control of maternal blood pressure with use of beta-blockers would be worthwhile only if it were reflected in substantive benefits for mother and/or baby, and none have been clearly demonstrated. The effect of beta-blockers on perinatal outcome is uncertain; the worrying trend to an increase in SGA infants is partly dependent on one small outlying trial. Large randomised trials are needed to determine whether antihypertensive therapy in general (rather than beta-blocker therapy specifically) results in greater benefit than risk, for treatment of mild-moderate pregnancy hypertension. If so, then it would be appropriate to consider which antihypertensive is best, and beta-blockers should be evaluated.
[Note: the seventeen reports in the awaiting classification section of the review may alter the conclusions of the review once assessed.]
Beta-adrenergic blocking agents in the treatment of pregnancy-induced hypertension.
Fifty-one women with pregnancy-induced hypertension (PIH) were randomly allocated to one of three treatment groups: A: hydralazine (13); B: hydralazine and propranolol (17); and C: hydralazine and pindolol (19). All women fulfilled the pretreatment criteria and were of similar age, numbers of previous pregnancies and had systolic blood pressure (SBP) of between 140 and 160 mmHg and diastolic blood pressure (DBP) of between 95 and 110 mmHg. Hypertension was treated equally well by all three regimens (mean SBP was 133.6, 130 and 134 mmHg, respectively). Heart rate was significantly higher than baseline in group A and lower in groups B and C, as is to be expected with beta-blocker treatment. Side-effects were more frequent in group A than in groups B and C, 62% of the patients on hydralazine monotherapy complained of palpitations compared to 35% on combination treatment. Fetal outcome differed in the various groups. Birth weight was significantly lower in group B, where regimen included propranolol, compared to that of group C, for whom the regimen included pindolol (3,044.7 +/- 443.8 and 2,709.6 +/- 485.5 gm, p < 0.05). Mean blood glucose of the newborns were similar in groups A and C (76.5 +/- 16.5 and 78.6 +/- 15 gm%) and significantly lower in group B (62.6 +/- 14 gm%, p < 0.02). In conclusion, blood pressure was equally well treated in all three treatment groups. However, more maternal side-effects occurred in group A, the group treated with hydralazine monotherapy, while propranolol in combination with hydrazaline (group B) had some negative effects on fetal development which did not occur in pindolol/hydrazaline combination.