What do systematic reviews say?

Antioxidants vs placebo or no treatment

It is very uncertain whether antioxidants changes live birth rate per couple randomised compared with placebo or no treatment (very low certainty).

• Antioxidants for male subfertility 2022 · Cochrane Headline outcomes only
  OR 1.43 [1.07, 1.91]
  12 studies · 1283 participants
  Very low

Antioxidants vs placebo or no treatment

Antioxidants may leads to higher clinical pregnancy rate per couple randomised compared with placebo or no treatment (low certainty).

• Antioxidants for male subfertility 2022 · Cochrane Headline outcomes only
  OR 1.89 [1.45, 2.47]
  20 studies · 1706 participants
  Low

Antioxidants vs placebo or no treatment

It is very uncertain whether antioxidants changes adverse events ‐ Miscarriage compared with placebo or no treatment (very low certainty).

• Antioxidants for male subfertility 2022 · Cochrane Headline outcomes only
  OR 1.46 [0.75, 2.83]
  6 studies · 664 participants
  Very low

Antioxidants vs placebo or no treatment

Antioxidants may leads to higher adverse events ‐ Gastrointestinal compared with placebo or no treatment (low certainty).

• Antioxidants for male subfertility 2022 · Cochrane Headline outcomes only
  OR 2.7 [1.46, 4.99]
  16 studies · 1355 participants
  Low

Antioxidants vs Placebo, no intervention or usual care (with or without placebo)

It is very uncertain whether antioxidant(s) changes live birth; antioxidants vs placebo or no treatment/standard… compared with placebo or no treatment/standard treatment (very low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 1.81 [1.36, 2.43]
  Studies not reported
  Very low

Antioxidants vs Placebo, no intervention or usual care (with or without placebo)

Antioxidant(s) may leads to higher clinical pregnancy; antioxidants vs placebo or no treatment/standard… compared with placebo or no treatment/standard treatment (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 1.65 [1.43, 1.89]
  Studies not reported
  Low

Intervention not reported

The intervention showed no clear difference in adverse events ‐ Miscarriage№ of participants: 304(3 RCTs) (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 1.54 [0.42, 5.67]
  Studies not reported
  Low

Intervention not reported

The review found no eligible studies for this question.

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Intervention not reported

The review found no eligible studies for this question.

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Intervention not reported

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  Very low

Antioxidants vs Placebo, no intervention or usual care (with or without placebo)

Antioxidant(s) showed no clear difference in adverse events ‐ Miscarriage№ of participants: 3229(24 RCTs) compared with placebo or no treatment/standard treatment (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 1.13 [0.82, 1.55]
  Studies not reported
  Low

Antioxidants vs Placebo, no intervention or usual care (with or without placebo)

Antioxidant(s) showed no clear difference in adverse events ‐ Multiple pregnancy№ of participants: 1886(9 RCTs) compared with placebo or no treatment/standard treatment (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 1 [0.63, 1.56]
  Studies not reported
  Low

Antioxidants vs Placebo, no intervention or usual care (with or without placebo)

Antioxidant(s) showed no clear difference in adverse events ‐ Gastrointestinal disturbances№ of participants:… compared with placebo or no treatment/standard treatment (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 1.55 [0.47, 5.1]
  Studies not reported
  Low

Antioxidants vs Placebo, no intervention or usual care (with or without placebo)

Antioxidant(s) showed no clear difference in adverse events ‐ Ectopic pregnancy№ of participants: 404(4 RCTs) compared with placebo or no treatment/standard treatment (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 1.4 [0.27, 7.2]
  Studies not reported
  Low

Intervention not reported

The intervention showed no clear difference in live birth; type of antioxidant (natural conceptions and undergoing… (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 0.94 [0.41, 2.15]
  Studies not reported
  Low

Intervention not reported

It is very uncertain whether the intervention changes clinical pregnancy; type of antioxidant (natural conceptions and… (very low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 0.81 [0.33, 2]
  Studies not reported
  Very low

Intervention not reported

The intervention showed no clear difference in clinical pregnancy; type of antioxidant (natural conceptions and… (low certainty).

• Antioxidants for female subfertility 2020 · Cochrane Headline outcomes only
  OR 0.94 [0.41, 2.15]
  Studies not reported
  Low