Chinese Herbal Medicine (New "Shoutai Wan") and/or Oral Progesterone Intervention Trial for Threatened Miscarriage

Threatened miscarriage is manifested by vaginal bleeding, with or without abdominal pain, while the cervix is closed and the fetus is viable and inside the uterine cavity. Threatened miscarriage is a common complication of pregnancy occurring in 20% of all clinically recognized pregnancies and about half of these will eventually result in pregnancy loss. The goal of this two by two factorial, placebo controlled randomized trial is to determine that two oral medications and their combination, will mostly likely result in live birth in women with threatened miscarriage. We will evaluate the efficacy and safety of Chinese herbal medicine (New "Shoutai Wan", NSTW) and/or oral micronized progesterone (OP) for treating threatened miscarriage in this trial. Our primary outcome of this trial is live birth. We hypothesize that: 1. treatment with NSTW plus OP or OP placebo is more likely to result in live birth than NSTW placebo plus OP or placebo; 2. treatment with OP plus NSTW or NSTW placebo is more likely to result in live birth than OP placebo plus NSTW or NSTW placebo; 3. treatment with combination of NSTW and OP is more likely to result in live birth than combination of NSTW placebo and OP placebo.