Objective  To investigate the effect of ritodrine hydrochloride combined with dydrogesterone tablets in the treatment of threatened abortion and its effect of hormone levels.

  Methods  Totally 120 patients with threatened abortion were selected and randomly divided into group A, B, and C, with 40 cases per group. The patients in three groups all given conventional care. Group A was treated with ritodrine hydrochloride, group B was treated with dydrogesterone tablets, and group C was treated with above drugs in combination. The hormonal levels of the three groups were compared, and the successful cases of abortion prevention and incidence of adverse reactions of the three groups were compared.

  Results  The levels of β-human chorionic gonadotropin(β-HCG), progesterone (P) and and estradiol (E₂) in the three groups were significantly higher after treatment than treatment before (P < 0.05), and were significantly higher in group C compared to groups A and B(62.50%). The successful rate of abortion prevention in group C was 95.00%, which was significantly higher than group A(67.50%) and B(P < 0.05). During the period of treatment, the incidence of adverse reactions was 20.00% in group A, 17.50% in group B and 20.00% in group C.

  Conclusion  Ritodrine hydrochloride combined with dydrogesterone tablets can improve the levels of β-HCG, P and E₂ in the treatment of patients with threatened abortion, and has a higher rate of fetal preservation and safety. The efficacy of drugs in combination is superior to single drug.