The measurement of hypoxia-inducible factor-1α and interleukin-6 levels in pregnancies with threatened preterm labor.

Background: Preterm birth has a significant impact on neonatal health and the healthcare system as it increases neonatal morbidities and mortality rates. Interleukin-6 is one of the pro-inflammatory cytokines that can trigger the production of chemokines and uterine activation proteins, consequently causing uterine contraction and subsequent cervical change. Hypoxia-inducible factor-1α plays a pivotal role in the hypoxic adaptive response of tissues. It has been suggested that hypoxia has a vital role in the initiating and/or strengthening of uterine contractions, proposing that hypoxia-inducible factor-1α could be involved in this process. Aim: Investigate whether serum concentrations of interleukin-6 and hypoxia-inducible factor-1α would differ between women with threatened preterm labor who deliver prematurely and those who continue their pregnancy till term. Patients and Methods: The case-control study was extended over 12 months, including women in their 28th to 35th weeks of gestation and with a single viable fetus. The women were divided into three groups: women with threatened preterm labor who delivered prematurely (27 women), women with threatened preterm labor who continued their pregnancy till term (23 women), and women with matching gestational age and uncomplicated pregnancies (the controls = 40 women). The serum levels of interleukin-6 and hypoxia-inducible factor-1α were measured by Enzyme-linked immunosorbent assay. Results: The mean values of interleukin-6 and hypoxia-inducible factor-1α were significantly different between the study groups (p-value <0.001 by one-way ANOVA), where women with threatened preterm labor who delivered prematurely had higher serum values of interleukin-6 and hypoxia-inducible factor-1α (124.5 and 102.4, respectively) than the women with threatened preterm labor who continued their pregnancy till term (71.0 and 55.2, respectively), and than the women in the control group (55.3 and 50.0, respectively). There was a significant negative statistical correlation between the values of interleukin-6 and hypoxia-inducible factor-1α and the timing of delivery (R = -0.786 and -0.644, respectively, p-value < 0.001). Conclusions: Both interleukin-6 and hypoxia-inducible factor-1a serum concentrations can help differentiate pregnant women who are genuinely in preterm labor from those who have preterm contractions but are not at risk of imminent delivery. [ABSTRACT FROM AUTHOR]