Comment: The quality of evidence is downgraded by study quality (few patients and a high risk of attrition bias and an unclear risk of bias due to potential carry-over effects in two cross-over trials).
A Cochrane review included 5 studies with a total of 305 subjects. Continuous oestrogen (transdermal patches or subcutaneous implants) with progestogen (sequential or continuous) versus placebo had a small to moderate positive effect on global symptom scores . One study comparing patch dosage (100 vs 200 µg oestrogen, with progestogen in both arms) did not find evidence that dosage affects global symptoms .
| Oestrogen in combination with progestogen Outcomes (over 2 to 4 menstrual cycles) | Relative effect (95% CI) | Risk with control -Placebo | Risk with intnervention - Oestrogen | № of participants (studies) Quality of evidence |
|---|---|---|---|---|
| Symptom scores | - | The difference in the mean change suggested a small to moderate benefit in the oestrogen group (SMD 0.27 lower, 95% CI 0.47 lower to 0.07 lower) | 158 (3) Very low | |
| Withdrawal due to adverse events | RR 0.64 (0.26 to 1.58) | 77 per 1000 | 49 per 1000 (20 to 122) | 196 (3) Very low |
| Oestrogen patch dose comparison Outcomes (8 months follow up) | Relative effect (95% CI) | Risk with control - Oestrogen 200 µg patch plus progestogen | Risk with intervention- Oestrogen 100 µg patch plus progestogen | № of participants (studies) Quality of evidence |
| Symptoms score: Premenstrual Daily Questionnaire (PDQ) Scale from 0 to 30, with a higher score indicating a worse outcome | - | The difference in the change was too imprecise to determine whether dosage had an effect (MD 1.55 lower, 95% CI 8.88 lower to 5.78 higher) | 98 (1) Very low | |
| Adverse events - withdrawal rates | RR 0.70 (0.34 to 1.46) | 255 per 1000 | 178 per 1000 (87 to 372) | 107 (1) Very low |
Date of latest search: 12 January 2018