RETRACTED: Oral dydrogesterone treatment during early pregnancy to prevent recurrent pregnancy loss and its role in modulation of cytokine production: a double-blind, randomized, parallel, placebo-controlled trial (Retracted article. See vol. 119, pg. 518, 2023)

Objective: To study the impact of administration of dydrogesterone in early pregnancy on pregnancy outcome and its correlation with Th1 and Th2 cytokine levels. Design: Double-blind, randomized, placebo-controlled study. Setting: A medical college and its associated hospital. Patient(s): Women with either: [1] a history of idiopathic recurrent pregnancy loss (RPL), in either a dydrogesterone group or a placebo group, or [2] no history of miscarriage. Intervention(s): Dydrogesterone 20 mg/day from confirmation of pregnancy to 20 weeks of gestation. Main Outcome Measure(s): Occurrence of another pregnancy loss and concentrations of T-helper (Th) 1 (interferon-gamma and tumor necrosis factor-alpha) and Th2 (interleukin (IL)-4 and IL-10) cytokines in serum at recruitment (4-8 weeks of gestation) and at abortion or 20 weeks of gestation, using commercially available ELISA kits. Result(s): Occurrence of another abortion after 3 consecutive abortions was significantly higher (29 of 173; 16.76%) in women with RPL compared with healthy pregnant controls (6 of 174; 3.45%). Risk of occurrence of miscarriage after 3 abortions was 2.4 times higher in the placebo group vs. the treatment group (risk ratio = 2.4, 95% CI = 1.3-5.9). Mean gestational age at delivery (excluding those aborted before 20 weeks of gestation) increased significantly in the dydrogesterone group (38.01 +/- 1.96 weeks) compared with the placebo group (37.23 +/- 2.41 weeks). Baby weight was significantly lower in the placebo group (2421.4 +/- 321.6 g) compared with the healthy pregnant controls (2545.3 +/- 554.3 g). At recruitment, serum IL-4 and tumor necrosis factor-alpha levels were significantly lower in the RPL group compared with the healthy pregnant controls. However, serum interferon-gamma level was significantly higher in the RPL group (8.87 +/- 0.72 pg/mL) compared with the healthy pregnant controls (8.08 +/- 1.27 pg/mL). Conclusion(s): The present study supports the use of dydrogesterone in women with recurrent abortions to improve pregnancy outcome, such as a reduction in abortions and improved gestational age and baby weight at delivery. However, these outcomes were not modulated by Th1 and Th2 cytokine production. (C) 2014 by American Society for Reproductive Medicine.