INFLUENCE OF OBSTRUCTIVE SLEEP APNEA ON OXIDATIVE STRESS IN PREGNANCY

Obstructive sleep apnea (OSA) is prevalent in pregnancy, and it is associated with adverse pregnancy-related outcomes such as gestational diabetes mellitus (GDM). Oxidative stress is proposed to be one of the main intermediate mechanisms. However, the effects of OSA on systemic oxidative stress are unknown in pregnancy. <bold>Methods:</bold> Women with normal pregnancy and with GDM in the 3rd trimester underwent hospital polysomnography to evaluate whether OSA increases oxidative stress. OSA was defined as an apnea–hypopnea index (AHI) ≥5 h-1. Serum from women and from cord blood was collected to determine protein carbonyl by the 2,4-dinitro-phenyl-hydrazine method. <bold>Results:</bold> 171 women were included with a median age of 34 years. The pregestational body mass index (BMI) was 23.2 (21-26.6) Kg/m2. OSA was found in 28 patients ((AHI 7.8 (5.9-10.1) h-1)), who were older and had higher BMI than 143 women with AHI<5 h-1. Protein carbonyl concentrations were not different according to OSA (AHI≥5 h-1), to REM-OSA (REM-AHI≥5 h-1), or to supine-OSA (supine- AHI≥5 h-1). After delivery, 86 cord blood samples were collected. No differences were found in protein carbonyl based on the presence of different criteria of OSA. Similar results were found in the sub-analysis of both normal pregnant women and GDM. However, we found significant correlations between mean obstructive apneas length and maternal and fetal protein carbonyl (r=-0.37 and r=-0.58, respectively). <bold>Conclusions:</bold> OSA in the 3rd trimester was not associated with higher protein carbonyl levels both in pregnant women and in cord blood samples. However, obstructive apneas length showed a significant relationship.