Mechanisms of the Maternal Exposome and Implications for Health Outcomes

Abstract

It is well established that the environment contributes to health. However, few studies have evaluated environmental exposures in women that may influence future health of their offspring. Knowledge gained may inform nursing how to better advocate for patients and families, and provide individualized interventions and education. Therefore, a more comprehensive investigation of the maternal exposome to uncover mechanistic insight into complex disease in offspring is warranted. To advance understanding of biologic mechanisms that contribute to high-risk birth outcomes and offspring predisposition to disease, it will be necessary to measure a range of exposures and biomarkers before and during pregnancy.

Figure 1. Relationship between Maternal Exposome and Health Outcomes of Offspring

The maternal exposome contains both exogenous and endogenous exposures that can be shared with the fetus during development. Exposures are specific time points have to potential to program predisposition for specific birth and adult health outcomes.

Figure 2. Exposome Penetrance

Exogenous factors in the maternal environment are also the exposome of the offspring while in utero. The exposure may impact fetal development by passing directly to the fetus or by altering maternal endogenous factors (i.e. hormones) that may alter the in utero environment. Exposures during development may alter predisposition to disease in the offspring.

Figure 3. Variables related to programming mechanisms

Endogenous and exogenous exposures during a woman’s life course contribute to the intrauterine environment and may influence vulnerability to disease at the level of the gamete as well as during the development of the fetus through alterations in microbiome composition, HPA axis responsiveness, DNA methylation, and telomere length. The offspring may exhibit altered health outcomes based on alterations to gametes prior to conception, exposures in utero, and throughout development. While the fetus is developing and forming gametes for the next generation, the gametes may be affected by the exposures and predispose the next generation to disease.