What do systematic reviews say?

Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes)

Any supplement containing iodine showed no clear difference in preterm birth compared with same supplement without iodine or no treatment/placebo (maternal… (low certainty).

• Iodine supplementation for women during the preconception, pregnancy and postpartum period 2017 · Cochrane Headline outcomes only
  RR 0.71 [0.3, 1.66]
  2 studies · 376 participants
  Low

Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes)

Any supplement containing iodine showed no clear difference in maternal adverse effect: elevated thyroid peroxidase antibodies ‐… compared with same supplement without iodine or no treatment/placebo (maternal… (low certainty).

• Iodine supplementation for women during the preconception, pregnancy and postpartum period 2017 · Cochrane Headline outcomes only
  RR 0.95 [0.44, 2.07]
  1 study · 359 participants
  Low

Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes)

Any supplement containing iodine showed no clear difference in maternal adverse effect: elevated TPO‐ab ‐ postpartum compared with same supplement without iodine or no treatment/placebo (maternal… (low certainty).

• Iodine supplementation for women during the preconception, pregnancy and postpartum period 2017 · Cochrane Headline outcomes only
  RR 1.01 [0.78, 1.3]
  3 studies · 397 participants
  Low

Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes)

Any supplement containing iodine showed no clear difference in maternal adverse effect: hyperthyroidism ‐ pregnancy compared with same supplement without iodine or no treatment/placebo (maternal… (low certainty).

• Iodine supplementation for women during the preconception, pregnancy and postpartum period 2017 · Cochrane Headline outcomes only
  RR 1.9 [0.57, 6.38]
  1 study · 365 participants
  Low

Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes)

Any supplement containing iodine showed no clear difference in maternal adverse effect: hyperthyroidism ‐ postpartum compared with same supplement without iodine or no treatment/placebo (maternal… (low certainty).

• Iodine supplementation for women during the preconception, pregnancy and postpartum period 2017 · Cochrane Headline outcomes only
  RR 0.32 [0.11, 1.91]
  3 studies · 543 participants
  Low

Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes)

It is very uncertain whether any supplement containing iodine changes maternal adverse effect: digestive intolerance ‐ pregnancy compared with same supplement without iodine or no treatment/placebo (maternal… (very low certainty).

• Iodine supplementation for women during the preconception, pregnancy and postpartum period 2017 · Cochrane Headline outcomes only
  RR 15.33 [2.07, 113.7]
  1 study · 76 participants
  Very low

Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes)

Any supplement containing iodine showed no clear difference in perinatal mortality compared with same supplement without iodine or no treatment/placebo (child… (low certainty).

• Iodine supplementation for women during the preconception, pregnancy and postpartum period 2017 · Cochrane Headline outcomes only
  RR 0.66 [0.42, 1.03]
  1 study · 399 participants
  Low

Recombinant human thyrotropin‐aided radioiodine vs radioiodine

• Recombinant human thyrotropin (rhTSH)‐aided radioiodine treatment for non‐toxic multinodular goitre 2021 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 85 participants
  Very low

Recombinant human thyrotropin‐aided radioiodine vs radioiodine

Recombinant human thyrotropin‐aided radioiodine probably leads to higher hypothyroidism compared with radioiodine (moderate certainty).

• Recombinant human thyrotropin (rhTSH)‐aided radioiodine treatment for non‐toxic multinodular goitre 2021 · Cochrane Headline outcomes only
  RR 2.53 [1.52, 4.2]
  6 studies · 321 participants
  Moderate

Recombinant human thyrotropin‐aided radioiodine vs radioiodine

Recombinant human thyrotropin‐aided radioiodine showed no clear difference in adverse events compared with radioiodine (low certainty).

• Recombinant human thyrotropin (rhTSH)‐aided radioiodine treatment for non‐toxic multinodular goitre 2021 · Cochrane Headline outcomes only
  RR 1.24 [0.94, 1.63]
  6 studies · 321 participants
  Low

Recombinant human thyrotropin‐aided radioiodine vs radioiodine

• Recombinant human thyrotropin (rhTSH)‐aided radioiodine treatment for non‐toxic multinodular goitre 2021 · Cochrane Headline outcomes only
  no estimate extracted
  6 studies · 268 participants
  Moderate

Recombinant human thyrotropin‐aided radioiodine vs radioiodine

• Recombinant human thyrotropin (rhTSH)‐aided radioiodine treatment for non‐toxic multinodular goitre 2021 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 28 participants
  Very low

Recombinant human thyrotropin‐aided radioiodine vs radioiodine

The review found no eligible studies for this question.

• Recombinant human thyrotropin (rhTSH)‐aided radioiodine treatment for non‐toxic multinodular goitre 2021 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Iodine tampon vs Saline irrigation (monoject syringe)

• Local interventions for the management of alveolar osteitis (dry socket) 2022 · Cochrane All outcomes

  Follow-up: median 7 days
  Iodine tampon versus rinsing with saline in a syringe (Tuk 2019): Iodine tampon 0/54 Monoject with saline 0/54; no events (effect not estimable)
  1 study · 108 participants
  GRADE not reported

Iodine supplementation vs control

Iodine supplementation showed no clear difference in mortality before hospital discharge compared with control (high certainty).

• Iodine supplementation for the prevention of mortality and adverse neurodevelopmental outcomes in preterm infants 2019 · Cochrane Headline outcomes only
  RR 1.01 [0.72, 1.42]
  2 studies · 1380 participants
  High

Iodine supplementation vs control

• Iodine supplementation for the prevention of mortality and adverse neurodevelopmental outcomes in preterm infants 2019 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 1259 participants
  High

Iodine supplementation vs control

• Iodine supplementation for the prevention of mortality and adverse neurodevelopmental outcomes in preterm infants 2019 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 1259 participants
  High

Iodine supplementation vs control

• Iodine supplementation for the prevention of mortality and adverse neurodevelopmental outcomes in preterm infants 2019 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 1259 participants
  High

Iodine supplementation vs control

Iodine supplementation showed no clear difference in low score in any main Bayley domain (< 85) or death compared with control (high certainty).

• Iodine supplementation for the prevention of mortality and adverse neurodevelopmental outcomes in preterm infants 2019 · Cochrane Headline outcomes only
  RR 1.05 [0.94, 1.17]
  1 study · 1259 participants
  High

Parachlorometaxylenol with iodine vs iodine alone

It is very uncertain whether parachlorometaxylenol with iodine changes surgical site infection compared with iodine alone (very low certainty).

• Skin preparation for preventing infection following caesarean section 2020 · Cochrane Headline outcomes only
  RR 0.33 [0.04, 2.99]
  1 study · 50 participants
  Very low