Hypertension during pregnancy, with and without specific hypotensive treatment. I. Perinatal factors and neonatal morbidity

In a prospective study, women who were hypertensive before the 28th wk of gestation were randomly allocated into two groups: those who received specific hypotensive therapy (Ht) and those who did not (Hu). The outcome was compared with a random sample of the hospital population (S) ascertained after delivery. In both hypertensive groups there was a higher incidence of clinical signs of possible fetal distress and instrumental delivery. Although there was no difference between the groups in the distribution of birthweight above and below the mean for gestational age, the treated hypertensive group had an excess of infants with relatively smaller head circumferences for their gestational age compared with both the untreated hypertensive group and the hospital sample. Tube-feeding was also more frequent in the treated hypertensive group. In the untreated hypertensive group there were more infants whose neurological status was categorized as questionable or abnormal in the neonatal period, compared with the sample. The different problems encountered by infants in the two hypertensive groups emphasized the need for further study of these babies. Their development during the first year of life will be examined in a subsequent paper.

Hypertension during pregnancy, with and without specific hypotensive treatment. II. The growth and development of the infant in the first year of life

The growth and development of three groups of infants were prospectively assessed from birth to 12 mth. In two groups the mothers had been hypertensive before the 28th wk of gestation; one group was randomly allocated to specific hypotensive therapy, the other group was allocated to no specific treatment. The third group was a sample of the hospital population. General health, and the incidence of sight and hearing problems did not differ. Infants in the treated hypertensive group had had more perinatal problems, and there was an excess of infants with relatively small heads for their gestational age at birth. At 6 mth their heads were still smaller than the hospital sample, but by the age of 1 yr the difference was no longer present. The neurological status of infants in the untreated hypertensive group was less favourable in the neonatal period, and there was still an excess of infants in this group rated questionable on neurological assessment at the age of 12 mth. In both hypertensive groups there was an excess of infants with delayed fine-motor function at 6 mth, and in the untreated group there was an excess with delayed gross-motor function at 12 mth compared with the hospital sample. Our varied findings draw attention to the dangers of assessing the effects of different pregnancy conditions in terms of neonatal mortality and morbidity alone. Our date indicate that follow-up should extend for longer than 12 mth when the effects of adverse pregnancy factors and their management are under consideration. Further evaluation will be made when these children are 4 yr old.

Treatment of hypertension in pregnancy with methyldopa: blood pressure control and side effects

A total of 242 women with moderate hypertension in pregnancy completed a controlled trial of methyldopa (Aldomet). The hypotensive effect of methyldopa was similar to its action in non-pregnant individuals and greatly reduced the frequency of severe hypertension occurring antenatally and in labour. As pregnancy advanced, an increasing daily dose of methyldopa was needed and there was a greater use of additional hypotensive therapy. Seventeen (14-5 per cent) women assigned to methyldopa had to be transferred to another drug or had to stop treatment completely because of minor side effects, of which the commonest were lack of energy and dizziness. No serious side effects were encountered. Nine per cent of the untreated women developed severe hypertension which required treatment later in their pregnancies. Six weeks after delivery, nearly all the patients were able to stop treatment.

Reversed diurnal blood pressure rhythm in hypertensive pregnancies

1. Reversal of the normal diurnal blood pressure pattern has been demonstrated in women with severe hypertension and renal impairment in pregnancy (pre-eclampsia). 2. Maximum arterial pressure occurred at night in these women. The phenomenon was not due to hypotensive drug therapy or posture. Patients with uncomplicated essential hypertension in pregnancy retained a normal diurnal blood pressure pattern. 3. Nocturnal hypertension in pre-eclampsia is of theoretical interest and practical importance.

Fetal outcome in trial of antihypertensive treatment in pregnancy

242 women completed a controlled trial of methyldopa ('Aldomet') for moderate hypertension in pregnancy. Active treatment was associated with a significantly improved fetal outcome, due in part to a reduced number of mid-pregnancy abortions. There were 9 pregnancy losses in the control group, which included 4 mid-pregnancy abortions, and 1 fetal loss in the treated group. The birthweight and maturity of viable infants were similar in treated and control groups, and a detailed multivariate analysis confirmed that hypotensive treatment had no effect on fetal growth in utero. The better outcome associated with treatment was not due to the prevention of pre-eclampsia, and may be partly due to a direct or indirect effect of methyldopa on uterine activity. Methyldopa is safe to use for the treatment of hypertension in pregnancy in the context of close medical and obstetric supervision.

Plasma-urate measurements in predicting fetal death in hypertensive pregnancy

The relation of perinatal mortality to plasma-urate concentrations and blood-pressure was studied in 332 pregnant patients with hypertension. Perinatal mortality was markedly increased when maternal plasma-urate concentrations were raised, generally in association with severe pre-eclampsia of early onset. Plasma-urate was a better indicator than blood-pressure of prognosis for the fetus. Maternal hypertension, even severe, without hyperuricaemia, was associated with an excellent prognosis for the fetus. Conversely, when maternal hypertension was mild and hyperuricaemia was severe, the prognosis for the fetus was poor. These findings suggest that, in terms of fetal health, changes in renal handling of urate may be a more important feature of pre-eclampsia than the hypertension.

Prolactin in hypertensive pregnancy

Plasma prolactin levels were measured in 68 pregnant women with hypertension at 32 weeks gestation. They were raised in pregnancies with pre-eclamptic features, most significantly in women with a rising plasma urate level. No correlation was found between the level of the untreated blood pressure and prolactin. Proteinuria did not influence prolactin levels independently of changes in the plasma urate. The differences in prolactin levels could not be ascribed to the drugs administered.