MIST

Question 1

Journal

Year

Answer 1

BMJ (published 17 May 2006)

Question 2

Aims

Answer 2

To ascertain whether a clinically important difference exists in the incidence of gynaecological infection between surgical management and expectant or medical management of miscarriage

Question 3

Study Design

Answer 3

RCT comparing medical and expectant management with surgical management of first trimester miscarriages

Question 4

Participants

Answer 4

• Early pregnancy assessment units of 7 hospitals in the UK
• 1200 women <13/40 with diagnosis of early fetal demise or incomplete miscarriage (399 conservative, 398 medical, 403 surgical)

Question 5

Inclusion Criteria

Answer 5

• Women with pregnancy of <13/40 with either incomplete miscarriage or early fetal/embryonic demise

Question 6

Exclusion Criteria

Answer 6

• Severe haemorrhage or pain, pyrexia above 37.5C, severe asthma, haemolytic disease or blood dyscrasias, current anticoagulation or systemic corticosteroid treatment, twin or higher order pregnancy, smoker aged >35, inability to understand written English

Question 7

Intervention

Answer 7

• Expectant management No specific intervention
• Medical management PV misoprostol preceded, for women with early fetal demise, by PO mifepristone 24-48 hours earlier
• Surgical management Surgical evacuation

Question 8

Primary end-points

Answer 8

Confimed gynaecological infection at 14 days and 8 weeks

• Definition = 2 or more of purulent discharge, pyrexia >38.0, tenderness over uterus, WCC >15

Question 9

Secondary end-points

Answer 9

Need for unplanned admission or surgical intervention, treatment with Abs for presumed gynaecological infection within 14/7 or 8/52, pain, additional analgesia, vaginal bleeding, days off work, days before return to usual daily activities, fall in Hb, blood transfusion, depression, anxiety

Question 10

Summary of results

Answer 10

• No differences found in incidence of confirmed infection within 14 days between expectant (3%) and surgical (3%) group, or between medical (2%) and surgical group
• Number of unplanned hospital admissions were significantly higher in both the expectant (49%) and medical (18%) group than surgical (8%)
• Number of unplanned surgical curettage was significantly higher in the expectant (44%) and medical (36%) group compared with surgical (5%)
• Cessation of bleeding significantly earlier in surgical group compared with medical group (did not affect Hb)
  o But 2% expectant and 1% medical required blood transfusion
• No significant difference in vomiting, diarrhoea, or pain
• Expectant management group required more analgesia
• No significant difference in time on leave, or return to work

Question 11

Limitations

Answer 11

• Unable to blind methods of management
• Lower than expected number of women recruited and took longer than expected
• Success rates of 3 options may be higher than this trial suggests, as women who choose a treatment option are likely to be more motivated to follow their chosen treatment to completion than women who are randomized
• Identified more retained products than you normally would in clinical practice because of routine ultrasound post treatment,