Cardiopulmonary resuscitation in pregnancy. What all nurses caring for childbearing women need to know

Ambient air pollution exposure and blood pressure changes during pregnancy

BACKGROUND

Maternal exposure to ambient air pollution has been associated with adverse birth outcomes such as preterm delivery. However, only one study to date has linked air pollution to blood pressure changes during pregnancy, a period of dramatic cardiovascular function changes.

OBJECTIVES

We examined whether maternal exposures to criteria air pollutants, including particles of less than 10 μm (PM(10)) or 2.5 μm diameter (PM(2.5)), carbon monoxide (CO), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), and ozone (O(3)), in each trimester of pregnancy are associated with magnitude of rise of blood pressure between the first 20 weeks of gestation and late pregnancy in a prospectively followed cohort of 1684 pregnant women in Allegheny County, PA.

METHODS

Air pollution measures for maternal ZIP code areas were derived using Kriging interpolation. Using logistic regression analysis, we evaluated the associations between air pollution exposures and blood pressure changes between the first 20 weeks of gestation and late pregnancy.

RESULTS

First trimester PM(10) and ozone exposures were associated with blood pressure changes between the first 20 weeks of gestation and late pregnancy, most strongly in non-smokers. Per interquartile increases in first trimester PM(10) and O(3) concentrations were associated with mean increases in systolic blood pressure of 1.88 mm Hg (95% CI=0.84 to 2.93) and 1.84 (95% CI=1.05 to 4.63), respectively, and in diastolic blood pressure of 0.63 mm Hg (95% CI=-0.50 to 1.76) and 1.13 (95% CI=-0.46 to 2.71) in non-smokers.

CONCLUSIONS

Our novel finding suggests that first trimester PM(10) and O(3) air pollution exposures increase blood pressure in the later stages of pregnancy. These changes may play a role in mediating the relationships between air pollution and adverse birth outcomes.

Maternal adaptations and inheritance in the transgenerational programming of adult disease

Adverse exposures in utero have long been linked with an increased susceptibility to adult cardio-renal and metabolic diseases. Clear gender differences exist, whereby growth-restricted females, although exhibiting some phenotypic modifications, are often protected from overt disease outcomes. One of the greatest physiological challenges facing the female gender, however, is that of pregnancy; yet little research has focused on the outcomes associated with this, as a potential 'second-hit' for those who were small at birth. We review the limited evidence suggesting that pregnancy may unmask cardio-renal and metabolic disease states and the consequences for long-term maternal health in females who were born small. Additionally, a growing area of research in this programming field is in the transgenerational transmission of low birth weight and disease susceptibility. Pathways for transmission might include an abnormal adaptation to pregnancy by the growth-restricted mother and/or inheritance via the parental germline. Strategies to optimise the pregnancy environment and/or prevent the consequences of inheritance of programmed deficits and dysfunction are of critical importance for future generations.