PRISM study

Question 1

Design?

Answer 1

A multicentre, double-blind, placebo-controlled, randomised trial of progesterone in women with
early pregnancy vaginal bleeding

Question 2

Objectives?

Answer 2

(1) To assess the effects of vaginal micronised progesterone in women with vaginal bleeding
in the first 12 weeks of pregnancy.

(2) To evaluate the cost-effectiveness of progesterone in women with
early pregnancy bleeding

Question 3

Participants?

Answer 3

4153 Women aged 16–39 years with early pregnancy bleeding.

Question 4

Intervention?

Answer 4

Women were randomly assigned to receive twice-daily vaginal suppositories containing either 400 mg of progesterone or a matched placebo from presentation
to 16 weeks of gestation

Question 5

Primary outcome?

Answer 5

live birth at ≥ 34 weeks

Also a cost effectiveness analysis

Question 6

Results?

Answer 6

No significance in the live birth rate: 75% in the progesterone group and 72% in the placebo, P=0.08

Sub-group analysis showed significant increased birth rate in women with:

• 3 or more miscarriages (72% vs 57%)
• Bleeding and 1 or more miscarriage (75% vs 70%)

Question 7

Exclusion criteria

Answer 7

• Ectopic pregnancy
• Very heavy bleeding (life threatening)
• USS already met criteria for miscarriage
• Medical contraindication to progesterone