Elevated gestational testosterone impacts vascular and uteroplacental function

Abstract

Maternal vascular adaptations to establish an adequate blood supply to the uterus and placenta are essential for optimal nutrient and oxygen delivery to the developing fetus in eutherian mammals, including humans. Numerous factors contribute to maintaining appropriate hemodynamics and placental vascular development throughout pregnancy. Failure to achieve or sustain these pregnancy-associated changes in women is strongly associated with an increased risk of antenatal complications, such as preeclampsia, a hypertensive disorder of pregnancy. The precise etiology of preeclampsia is unknown, but emerging evidence points to a potential role for androgens. The association between androgens and maternal cardiovascular and placental function merits particular attention due to the notable 2- to 3-fold elevated plasma testosterone (T) levels observed in preeclampsia. T levels in preeclamptic women positively correlate with vascular dysfunction, and preeclampsia is associated with increased androgen receptor (AR) levels in placental tissues. Moreover, animal studies replicating the pattern and magnitude of T increase observed in preeclamptic pregnancies have reproduced key features of preeclampsia, including gestational hypertension, endothelial dysfunction, heightened vasoconstriction to angiotensin II, impaired spiral artery remodeling, placental hypoxia, reduced nutrient transport, and fetal growth restriction. Collectively, these findings suggest that AR-mediated activity plays a significant role in the clinical presentation of preeclampsia. This review critically evaluates this hypothesis, considering both clinical and preclinical evidence.

Keywords: Androgens; Endothelium; Nutrient transport; Placenta; Preeclampsia; Trophoblast.

Figure 1.

The mean total (A) and free (B) testosterone levels in preeclamptic pregnancies and their normotensive controls, as reported in published studies [–37]. Each data point represents the testosterone levels measured in a single published study.

Figure 2.

Comprehensive vascular and uteroplacental consequences of elevated maternal testosterone during pregnancy. Elevated testosterone levels cause systemic, uterine, and placental vascular dysfunction, leading to increased blood pressure, decreased uterine artery blood flow, and placental insufficiency, which may contribute to fetal growth restriction.