Correction of Neonatal Glutathione by N-acetylcysteine in Pregnant Women at Risk of Premature Birth (GSH MAP)

Birth exposes the newborn to oxidative stress, as due to the switch from a protected, relatively hypoxic intrauterine milieu into an environment with a high oxygen pressure. The full-term newborn is well prepared to this massive redox challenge at the time of birth due to his well-integrated antioxidant defenses. On the contrary, numerous bibliographical data and our own work demonstrate the fragility of preterm newborns in this context of oxidative stress, linked to the immaturity of his antioxidant defenses. Premature birth abruptly propels the fetus from the protected, relatively hypoxic intrauterine milieu to an environment at risk of free radical injury caused by mechanical ventilation strategies, including the use of high inspired oxygen fractions or inhaled nitric oxide, generating excessive reactive oxidative species (ROS). Several studies highlight the key role of ROS in adverse outcomes of preterm infant suffering from low birth weight, bronchopulmonary dysplasia, necrotizing enterocolitis or retinopathy. This project aims to evaluate a therapeutic anti-oxidative strategy in order to correct the oxidative status of preterm infants. The investigators propose an early intervention that consists in an antenatal maternal supplementation with N-acetylcysteine (NAC), the acetylated precursor of both cysteine and glutathione, a key physiological antioxidant. This strategy could be promising for the development of simplified and personalized care of preterm infants. GSH MAP is a randomized, single-blind, placebo-controlled study that aims to determine if NAC supplementation in women admitted to hospital care due to preterm labor (prior to 34 weeks of gestational age) may correct glutathione deficiency in neonatal cord blood.

GSH MAP is a randomized single-blind, placebo-controlled study. The design will include the recruitment of 120 pregnant women admitted to hospital care due to preterm labor (above 18 yrs of age, gestational age between 24 and 34 weeks). According to the risk of preterm delivery, women will be treated following two different schedules : * High risk of prematurity: NAC supplementation -9 g intravenously-6g/day per os until day 7-1,8g/day per os until 37 weeks of gestational age. * Moderate risk of prematurity: NAC supplementation -6g/day per os until day 7-1,8g/day per os until 37 weeks of gestational age. Biological samples collected: maternal blood at inclusion, maternal/cord blood and placenta at delivery, breast milk samples during the first week of lactation in case of exclusive breastfeeding. Levels of glutathione and related metabolites will be measured in plasma, red blood cells, placenta and breast milk. In ancillary studies, metabolome and lipidome profilings will be performed on maternal and cord blood and on breast milk samples.