WHO 1980.

Methods	Location and time frame: Hungary, Belgium, Brazil, United Kingdom, Chile, and Germany Design: RCT at 6 centers Sample size calculation and outcome of focus: no mention
Participants	General with N: 841 healthy women Inclusion criteria: aged 16 to 40 years; having vaginal delivery; willing to rely on IUD for fertility regulation Exclusion criteria: recent history of pelvic inflammatory disease; sexually transmitted infection treated during current pregnancy; congenital abnormality of uterus or vagina; known or suspected genital tract malignancy; uterine fibroids; or evidence of infection during labor
Interventions	IUD inserted immediately after expulsion of placenta Copper 7 (Gravigard) Lippes Loop D Postpartum T (T‐shaped IUD with two extra arms, 2‐cm long, extending up and out from lower end of vertical stem) Insertions were done with standard or modified IUD inserter or by manual placement at fundus.
Outcomes	Reported expulsion (partial or complete), pregnancy, removal for bleeding or pain, and other medical removal Assessment times: 6 and 12 months; follow‐up to 24 months
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomization by computer‐generated table of numbers (from communication with investigators)
Allocation concealment (selection bias)	Low risk	Sealed, opaque, sequentially numbered envelopes with method indicator card (from communication with investigators)
Blinding of participants and personnel (performance bias) All outcomes	High risk	No blinding
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Trial was stopped prematurely because expulsion rates with all devices exceeded predetermined 20% limit. Women with expulsion within 48 hours after insertion were excluded from life‐table analysis (part of protocol). Loss to follow‐up (reported; time frame unclear): Postpartum T, 17.8%; Lippes Loop, 16.2%; Copper 7, 16%