No abstract

This document reflects emerging clinical and scientific advances on the date issued and is subject to change. The information should not be construed as dictating an exclusive course of treatment or procedure to be followed. Local institutions can dictate amendments to these opinions. They should be well documented if modified at the local level. None of these contents may be reproduced in any form without prior written permission of the SOGC.

No abstract

A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. BACKGROUNDThe effects of less-tight versus tight control of hypertension on pregnancy complications are unclear. METHODSWe performed an open, international, multicenter trial involving women at 14 weeks 0 days to 33 weeks 6 days of gestation who had nonproteinuric preexisting or gestational hypertension, office diastolic blood pressure of 90 to 105 mm Hg (or 85 to 105 mm Hg if the woman was taking antihypertensive medications), and a live fetus. Women were randomly assigned to less-tight control (target diastolic blood pressure, 100 mm Hg) or tight control (target diastolic blood pressure, 85 mm Hg). The composite primary outcome was pregnancy loss or high-level neonatal care for more than 48 hours during the first 28 postnatal days. The secondary outcome was serious maternal complications occurring up to 6 weeks post partum or until hospital discharge, whichever was later. RESULTSIncluded in the analysis were 987 women; 74.6% had preexisting hypertension. The primary-outcome rates were similar among 493 women assigned to less-tight control and 488 women assigned to tight control (31.4% and 30.7%, respectively; adjusted odds ratio, 1.02; 95% confidence interval [CI], 0.77 to 1.35), as were the rates of serious maternal complications (3.7% and 2.0%, respectively; adjusted odds ratio, 1.74; 95% CI, 0.79 to 3.84), despite a mean diastolic blood pressure that was higher in the less-tight-control group by 4.6 mm Hg (95% CI, 3.7 to 5.4). Severe hypertension (≥160/110 mm Hg) developed in 40.6% of the women in the less-tight-control group and 27.5% of the women in the tight-control group (P<0.001). CONCLUSIONSWe found no significant between-group differences in the risk of pregnancy loss, high-level neonatal care, or overall maternal complications, although less-tight control was associated with a significantly higher frequency of severe maternal hypertension. (Funded by the Canadian Institutes of Health Research; CHIPS Current Controlled Trials number, ISRCTN71416914; ClinicalTrials.gov number, NCT01192412.) a bs tr ac t

Three main conditions explain preterm birth: medically indicated (iatrogenic) preterm birth (25%; 18.7–35.2%), preterm premature rupture of membranes (PPROM) (25%; 7.1–51.2%) and spontaneous (idiopathic) preterm birth (50%; 23.2–64.1%). The majority of multiple pregnancies (10% of all preterm births) are delivered preterm (50% for medical reasons). Although medical indications relate more to feto‐maternal conditions, PPROM to infections and idiopathic preterm birth to lifestyle, these risk factors are identified in any category, emphasising that preterm birth has a multifactorial origin. Still, several incidences of preterm birth are not completely explained with a plausible cause for PPROM or spontaneous preterm labour suggesting that other causes have yet to be identified. In addition, preterm birth is associated with unrecognised severe congenital anomalies. Variability within the main categories may be explained by the studied population, ethnic group, social class and preventive interventions towards reducing spontaneous preterm birth where the proportion of medically‐indicated preterm birth is increased. Despite being retrospective a classification according to gestational age at birth is important for neonatal prognosis. Preterm birth is stratified into mild preterm (32–36 weeks), very preterm (28–31 weeks) and extremely preterm (<28 weeks) with increasing neonatal mortality and morbidity. Recent studies suggested that infection was mostly responsible for extreme preterm birth, while stress and lifestyle accounted for mild preterm birth, and a mixture of both conditions contributed to very preterm birth.