Effects of Different Progesterone Doses on the Concentrations of Proinflammatory and Anti-inflammatory Cytokines in Pregnant Women With Threatened Abortion

Background and objective This study aimed to investigate how different doses of progesterone influence the concentrations of interleukin-6 (IL-6) and tumor necrotizing factor-alpha (TNF-α), which are proinflammatory cytokines, as well as that of IL-10, which is an anti-inflammatory cytokine, in pregnant women with threatened abortion. Materials and methods This is a prospective, single-center, randomized controlled trial conducted with 221 patients with a threatened abortion diagnosis. Group 1 consisted of IL-6, IL-10, and TNF-α values in pre-treatment blood samples from 221 patients diagnosed with imminent abortion. Group 2 included 81 patients who received natural oral 100 mg micronized progesterone MP twice a day for two weeks. Group 3 included 83 patients who were administered oral 200 mg of natural micronized progesterone MP twice a day for two weeks. Group 4 included 57 patients who received oral 200 mg of natural micronized progesterone MP twice a day for two weeks, and one depot progesterone was added to the treatment by administering it at a dosage of 500 mg/day intramuscularly. Results IL-6 values between groups were lower in group 4 compared to group 3 (p=0.007). When IL-10 values were compared between the groups, the IL-10 ratio was highest in group 4 and lowest in group 2 (p<0.001, p=0.003, p<0.001). When the TNF-α values between the groups were compared, the value in group 4 was decreased compared to groups 1 and 2 (p=0.031, p<0.001). In the logistic regression analysis, the IL-6 value above 12.01 increased the abortion imminens rate 1.01 times, and a TNF-α value above 11.04 increased the abortion imminens rate 1.21 times. Conclusion Progesterone used to treat imminent abortion reduces the levels of proinflammatory cytokines, such as IL-6 and TNF-α, while increasing those of anti-inflammatory cytokine IL-10 in proportion to the dose administered. Progesterone can prevent imminent abortion by generating an anti-inflammatory environment.