Alterations in the maternal peripheral microvascular response in pregnancies complicated by preeclampsia and the impact of fetal sex.

Objective: Peripheral microvascular function is altered in preeclampsia (PE). Recent studies suggest that maternal physiology varies with fetal sex. We wanted to examine if there were sex-specific differences in maternal peripheral microvascular function in normal pregnancy and pregnancy complicated by PE.

Methods: Peripheral microvascular responses were examined using the noninvasive technique of laser Doppler flowmetry in normotensive healthy pregnant women and in women diagnosed with PE. We measured baseline perfusion, response to thermal hyperemia, post-occlusive reperfusion, and vasodilatation in response to corticotropin-releasing hormone (CRH), a potent vasodilator in human skin.

Results: At 31 to 40 weeks' gestation those women with a male fetus exhibited increased vasodilatation in response to CRH (P <.05) and greater baseline perfusion (P <.05) than those pregnant with a female fetus. PE women pregnant with a male fetus demonstrated a significantly reduced vasodilatation in response to CRH (P <.05), reduced baseline perfusion (P <.05), and reduced response to thermal hyperemia (P <.05) compared to normotensive women pregnant with a male fetus. Microvascular function was not significantly different between preeclamptic and normotensive women with a female fetus.

Conclusion: These data show that there are differences in maternal peripheral microvascular function in relation to fetal sex.