Table 2

Summary of findings on the risk of hospitalisation and intubation among COVID-19 patients in tertiary care settings using any type of hormonal contraception compared with those using no form or hormonal contraception

Outcomes*Anticipated absolute effects† (95% CI)Relative effect
(95% CI)		Number of participants
(studies)		Certainty of the evidence
(GRADE)
Risk with no contraceptionRisk with any type of hormonal contraception (oestrogen plus progestin or progestin-only)
Hospitalisation38 per 100038 per 1000
(26 to 54)		OR 0.99
(0.68 to 1.44)		123
(1 observational study)		⊕⊝⊝⊝
Very lowद
Intubation0 of 79 patients who did not use hormonal contraception required intubation compared with 0 of 44 patients who used hormonal contraception.123
(1 observational study)		⊕⊝⊝⊝
Very lowद

  • GRADE Working Group grades of evidence

  • High certainty: we are very confident that the true effect lies close to that of the estimate of the effect.

  • Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.

  • Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect.

  • Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.

  • *The outcomes of mortality, VTE, arterial thromboembolism, and ARDS were not measured and are not included in this table.

  • †The risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

  • ‡Downgraded for serious risk of bias given no ascertainment of hormonal contraception exposure and no information on variables used for adjustment, increasing risk of residual confounding.

  • §Downgraded for indirectness as the study was not performed in patients confirmed to be using contraception at time of outcome.

  • ¶Downgraded 2 levels for imprecision due to small sample size with wide CI with results reported in only 1 study.

  • ARDS, acute respiratory distress syndrome; VTE, venous thromboembolism.