OBJECTIVES: We searched CENTRAL, MEDLINE, Embase and CINAHL to January 2021.
SELECTION CRITERIA: This review includes 21 trials involving 3689 participants from middle- and high-income countries. Women were 18 to 45 years old and either already using an IUD or had just had one placed for
contraception. The included trials examined
NSAIDs and other interventions. Eleven were treatment trials, of these seven were on users of the Cu IUD, one on LNG IUD and three on an unknown type. Ten were prevention trials, six focused on Cu IUD users, and four on LNG IUD users. Sixteen trials had high risk of detection bias due to subjective assessment of
pain and
bleeding. Treatment of
heavy menstrual bleeding Cu IUD
Vitamin B1 resulted in fewer pads used per day (mean difference (MD) -7.00, 95% confidence interval (CI) -8.50 to -5.50) and fewer
bleeding days (MD -2.00, 95% CI -2.38 to -1.62; 1 trial; 110 women; low-certainty evidence) compared to placebo. The evidence is very uncertain about the effect of
naproxen on the volume of menstruation compared to placebo (odds ratio (OR) 0.09, 95% CI 0.00 to 1.78; 1 trial, 40 women; very low-certainty evidence). Treatment with
mefenamic acid resulted in less volume of blood loss compared to
tranexamic acid (MD -64.26, 95% CI -105.65 to -22.87; 1 trial, 94 women; low-certainty evidence). However, there was no difference in duration of
bleeding with treatment of
mefenamic acid or
tranexamic acid (MD 0.08 days, 95% CI -0.27 to 0.42, 2 trials, 152 women; low-certainty evidence). LNG IUD The use of
ulipristal acetate in LNG IUD may not reduce the number of
bleeding days in 90 days in comparison to placebo (MD -9.30 days, 95% CI -26.76 to 8.16; 1 trial, 24 women; low-certainty evidence). Unknown IUD type
Mefenamic acid may not reduce volume of
bleeding compared to Vitex agnus measured by pictorial blood assessment chart (MD -2.40, 95% CI -13.77 to 8.97; 1 trial; 84 women; low-certainty evidence). Treatment of
pain Cu IUD Treatment with
tranexamic acid and
sodium diclofenac may result in little or no difference in the occurrence of
pain (OR 1.00, 95% CI 0.06 to 17.25; 1 trial, 38 women; very low-certainty evidence). Unknown IUD type
Naproxen may reduce
pain (MD 4.10, 95% CI 0.91 to 7.29; 1 trial, 33 women; low-certainty evidence). Prevention of
heavy menstrual bleeding Cu IUD We found very low-certainty evidence that
tolfenamic acid may prevent heavy
bleeding compared to placebo (OR 0.54, 95% CI 0.34 to 0.85; 1 trial, 310 women). There was no difference between
ibuprofen and placebo in blood volume reduction (MD -14.11, 95% CI -36.04 to 7.82) and duration of
bleeding (MD -0.2 days, 95% CI -1.40 to 1.0; 1 trial, 28 women, low-certainty evidence).
Aspirin may not prevent heavy
bleeding in comparison to
paracetamol (MD -0.30, 95% CI -26.16 to 25.56; 1 trial, 20 women; very low-certainty evidence). LNG IUD
Ulipristal acetate may increase the percentage of
bleeding days compared to placebo (MD 9.50, 95% CI 1.48 to 17.52; 1 trial, 118 women; low-certainty evidence). There were insufficient data for analysis in a single trial comparing
mifepristone and
vitamin B. There were insufficient data for analysis in the single trial comparing
tranexamic acid and
mefenamic acid and in another trial comparing
naproxen with
estradiol. Prevention of
pain Cu IUD There was low-certainty evidence that
tolfenamic acid may not be effective to prevent
painful menstruation compared to placebo (OR 0.71, 95% CI 0.44 to 1.14; 1 trial, 310 women).
Ibuprofen may not reduce menstrual
cramps compared to placebo (OR 1.00, 95% CI 0.11 to 8.95; 1 trial, 20 women, low-certainty evidence).
AUTHORS' CONCLUSIONS: