A randomized trial of tight vs. less tight control of mild essential and gestational hypertension in pregnancy. The Control of Hypertension In Pregnancy Study pilot trial.
To assess the effects of applying a tight vs. a less tight control of mild chronic essential or gestational non-proteinuric hypertension in pregnancy.
                A randomized trial was conducted in 2006-2007 in the University of Ain Shams, Egypt. Eligible participants (n=125) were randomly assigned to either tight or less tight control of mild chronic (essential) or gestational (non-proteinuric) hypertension. The primary outcome measure was the development of severe hypertension during follow-up. Analysis was by intention-to-treat.
                In the tight target group, adjustment of the dose with an increment of 191 mg yielded a mean dose of methyldopa of 1267+/-406 mg. Both systolic and diastolic BP levels were significantly less than in the tight target group. More women in the less tight group had severe hypertension during follow up (RR 3.167 and 95% CI 1.36-7.37). The rate of antenatal hospitalization was significantly higher in the less tight target group with a relative risk of 2.57 and 95% CI 1.16-5.70. The gestational age at delivery was significantly better in the tight target group. Preterm delivery and birth weight were not significantly different between the study groups.
                Tight control of blood pressure reduces the rate of antenatal hospitalization and does not adversely affect perinatal outcomes in women with mild essential or gestational hypertension. To determine whether 'less tight' (versus 'tight') control of nonsevere hypertension results in a difference in diastolic blood pressure (dBP) between groups.
                Randomised controlled trial (ISRCTN#57277508).
                Seventeen obstetric centres in Canada, Australia, New Zealand, and UK.
                Inclusion: pregnant women, dBP 90-109 mmHg, pre-existing/gestational hypertension; live fetus(es); and 20-33(+6) weeks. Exclusion: systolic blood pressure > or = 170 mmHg and proteinuria, contraindication, or major fetal anomaly.
                Randomisation to less tight (target dBP, 100 mmHg) or tight (target dBP, 85 mmHg) blood pressure control.
                Primary: mean dBP at 28, 32 and 36 weeks. Secondary: clinician compliance and women's satisfaction. Other: serious perinatal and maternal complications.
                A total of 132 women were randomised to less tight (n = 66; seven had no study visit) or tight control (n= 66; one was lost to follow up; seven had no study visit). Mean dBP was significantly lower with tight control: -3.5 mmHg, 95% credible interval (-6.4, -0.6). Clinician compliance was 79% in both groups. Women were satisfied with their care. With less tight (versus tight) control, the rates of other treatments and outcomes were the following: post-randomisation antenatal antihypertensive medication use: 46 (69.7%) versus 58 (89.2%), severe hypertension: 38 (57.6%) versus 26 (40.0%), proteinuria: 16 (24.2%) versus 20 (30.8%), serious maternal complications: 3 (4.6%) versus 2 (3.1%), preterm birth: 24 (36.4%) versus 26 (40.0%), birthweight: 2675 +/- 858 versus 2501 +/- 855 g, neonatal intensive care unit (NICU) admission: 15 (22.7%) versus 22 (34.4%), and serious perinatal complications: 9 (13.6%) versus 14 (21.5%).
                The CHIPS pilot trial confirms the feasibility and importance of a large definitive trial to determine the effects of less tight control on serious perinatal and maternal complications.