Tramadol (versus unexposed) updated on 07-09-2025

Early intrauterine deaths (< 22 weeks) / Spontaneous abortions

R analysis
id Study   Lib. in paper Exposition period    Study type 
 Control type 
 
Tags OR 95%CI x1/n1 x0/n0 no cases no exposed ROB Ref.
S18427
R77990		 Ferrer, 2025 Early termination (< 22 weeks of amenorrhea) during pregnancy (anytime or not specified) retrospective cohort (claims database) unexposed (general population or NOS) Adjustment: No 2.09 [1.78;2.47] C 160/1,602   7,972/158,426 8,132 1,602
ref
S13280
R51162		 Sørensen, 2022 Spontaneous abortion (pregnancy ending from 6 through 22 completed gestational weeks) early pregnancy population based cohort retrospective unexposed (general population or NOS) Adjustment: Yes 1.06 [0.99;1.14] 893/7,310   3,471/29,157 4,364 7,310
ref
S13270
R51119		 Gouraud, 2010 Spontaneous abortions 1st trimester prospective cohort unexposed (general population or NOS) Adjustment: No Matched 3.71 [2.11;6.52] C 20/130   44/941 64 130
ref
Total 3 studies 1.92 [1.04;3.53] 12,560 9,042
x1: number of endpoints among exposed, n1: number of exposed; x0: number of endpoints among non exposed, n0: number of non exposed; C: calculated odds ratio from numbers of events and effectives

Forest plot

StudyTE95% CIn casesn exposedweightROBABCDEF Ferrer, 2025Ferrer, 2025 2.09[1.78; 2.47]8,1321,60236%ROB confusion: criticalROB selection: lowROB classification: moderateROB missing: lowROB mesure: moderateROB reporting: moderate Sørensen, 2022Sørensen, 2022 1.06[0.99; 1.14]4,3647,31036%ROB confusion: seriousROB selection: moderateROB classification: criticalROB missing: moderateROB mesure: moderateROB reporting: moderate Gouraud, 2010Gouraud, 2010 3.71[2.11; 6.52]6413028%ROB confusion: criticalROB selection: moderateROB classification: moderateROB missing: unclearROB mesure: moderateROB reporting: moderate Total (3 studies) I2 = 97% 1.92[1.04; 3.53]12,5609,0420.510.01.0ROB: A: confusion, B: selection, C: classification, D: missing, E: measurement, F: reportinglow,moderate,serious,critical,unclear,

Sensitivity analysis

SubsetTE95% CIn casesn exposedkI2 Type of studies cohort studiescohort studies 1.92[1.04; 3.53]12,5609,04297%NAFerrer, 2025 Sørensen, 2022 Gouraud, 2010 3 case control studiescase control studies 0 Type of controls unexposed (disease free or unspecified)unexposed (disease free or unspecified) 1.92[1.04; 3.53]12,5609,04297%NAFerrer, 2025 Sørensen, 2022 Gouraud, 2010 3 Tags Adjustment   - No  - No 2.61[1.51; 4.49]8,1961,73272%NAFerrer, 2025 Gouraud, 2010 2   - Yes  - Yes 1.06[0.99; 1.14]4,3647,310 -NASørensen, 2022 1 MatchedMatched 3.71[2.11; 6.52]64130 -NAGouraud, 2010 1 All studiesAll studies 1.92[1.04; 3.53]12,5609,04297%NAFerrer, 2025 Sørensen, 2022 Gouraud, 2010 30.510.01.0

Publication bias and p-hacking diagnosis

funnel plot

Funnel plot not drawn. Less than 3 points.

Asymetry test p-value = NaN (by Egger's regression)

not enought points

p values plot

Funnel plot not drawn. Less than 3 points.

Sub-groups analysis using all included studies

excluded

Sub-groupsTE95% CIn casesn exposedkI2ROB type of controls unexposed controls (disease free or unspecified)unexposed controls (disease free or unspecified) 1.92[1.04; 3.53]12,5609,04297%NAFerrer, 2025 Sørensen, 2022 Gouraud, 2010 30.510.01.0