Gabapentin (Epilepsy) updated on 04-22-2025

Major congenital malformations

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.
S18712
R79617		 The NAAED (Gabapentin) (Epilepsy), 2025 Major congenital malformations 1st trimester prospective cohort exposed to other treatment, sick Adjustment: No 0.22 [0.01;3.61] C 0/107   40/1,944 40 107
ref
S16707
R70291		 Battino, 2024 Major congenital malformations (MCMs) early pregnancy prospective cohort exposed to other treatment, sick Adjustment: No 0.88 [0.12;6.46] C 1/37   110/3,584 111 37
ref
S6252
R16647		 Arkilo (Gabapentin), 2015 Major malformations during pregnancy (anytime or not specified) excluded retrospective cohort exposed to other treatment, sick Adjustment: No 47.00 [0.38;5814.69] C
excluded (exposition period) 		0/1   0/24 0 1
ref
S6379
R17374		 Vajda (Gabapentin) (Controls exposed to Lamotrigine, sick), 2013 Fetal malformations at least 1st trimester prospective cohort exposed to other treatment, sick excluded Adjustment: No 0.83 [0.05;14.66] C
excluded (control group) 		0/14   13/315 13 14
ref
S6370
R17365		 Vajda (Gabapentin) (Controls unexposed, sick), 2013 Fetal malformations at least 1st trimester prospective cohort unexposed, sick Adjustment: No 0.95 [0.05;18.18] C 0/14   5/147 5 14
ref
S8274
R26216		 Mawer (Gabapentin) (Controls exposed to Lamotrigine, sick), 2010 Major malformations 1st trimester prospective cohort exposed to other treatment, sick excluded Adjustment: No 4.60 [0.15;144.69] C
excluded (control group) 		0/2   2/37 2 2
ref
S8276
R26218		 Mawer (Gabapentin) (Controls unexposed, disease free), 2010 Major malformations 1st trimester prospective cohort unexposed, disease free excluded Adjustment: No Matched 14.28 [0.53;384.83] C
excluded (control group) 		0/2   6/285 6 2
ref
S8278
R26220		 Mawer (Gabapentin) (Controls unexposed, sick), 2010 Major malformations 1st trimester prospective cohort unexposed, sick Adjustment: No 8.78 [0.24;318.70] C 0/2   1/41 1 2
ref
S6060
R15750		 Morrow (Gabapentin) (Controls exposed to Lamotrigine, sick), 2006 Major congenital malformation 1st trimester prospective cohort exposed to other treatment, sick excluded Adjustment: No 0.99 [0.13;7.64] C
excluded (control group) 		1/31   21/647 22 31
ref
S6059
R15749		 Morrow (Gabapentin) (Controls unexposed, sick), 2006 Major congenital malformation 1st trimester prospective cohort unexposed, sick Adjustment: No 0.91 [0.11;7.55] C 1/31   8/227 9 31
ref
S6682
R18545		 Dean (Gabapentin), 2002 Major congenital malformations at least 1st trimester retrospective cohort unexposed, sick Adjustment: No 14.20 [0.23;878.06] C 0/1   2/38 2 1
ref
Total 6 studies 1.09 [0.37;3.21] 168 192
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 The NAAED (Gabapentin) (Epilepsy), 2025The NAAED, 2025 1 0.22[0.01; 3.61]4010715%ROB confusion: criticalROB selection: unclearROB classification: moderateROB missing: unclearROB mesure: criticalROB reporting: low Battino, 2024Battino, 2024 0.88[0.12; 6.46]1113729%ROB confusion: criticalROB selection: moderateROB classification: moderateROB missing: moderateROB mesure: moderateROB reporting: moderate Vajda (Gabapentin) (Controls unexposed, sick), 2013Vajda, 2013 2 0.95[0.05; 18.18]51413%ROB confusion: NAROB selection: NAROB classification: NAROB missing: NAROB mesure: NAROB reporting: NA Mawer (Gabapentin) (Controls unexposed, sick), 2010Mawer, 2010 3 8.78[0.24; 318.70]129%ROB confusion: criticalROB selection: moderateROB classification: lowROB missing: moderateROB mesure: moderateROB reporting: moderate Morrow (Gabapentin) (Controls unexposed, sick), 2006Morrow, 2006 4 0.91[0.11; 7.55]93126%ROB confusion: NAROB selection: NAROB classification: NAROB missing: NAROB mesure: NAROB reporting: NA Dean (Gabapentin), 2002Dean, 2002 5 14.20[0.23; 878.06]217%ROB confusion: NAROB selection: NAROB classification: NAROB missing: NAROB mesure: NAROB reporting: NA Total (6 studies) I2 = 0% 1.09[0.37; 3.21]1681920.250.01.0ROB: A: confusion, B: selection, C: classification, D: missing, E: measurement, F: reportinglow,moderate,serious,critical,unclear,

1: Gabapentin) (Epilepsy; 2: Gabapentin) (Controls unexposed, sick; 3: Gabapentin) (Controls unexposed, sick; 4: Gabapentin) (Controls unexposed, sick; 5: Gabapentin;

Sensitivity analysis

SubsetTE95% CIn casesn exposedkI2 Type of studies cohort studiescohort studies 1.09[0.37; 3.21]1681920%NAThe NAAED (Gabapentin) (Epilepsy), 2025 Battino, 2024 Vajda (Gabapentin) (Controls unexposed, sick), 2013 Mawer (Gabapentin) (Controls unexposed, sick), 2010 Morrow (Gabapentin) (Controls unexposed, sick), 2006 Dean (Gabapentin), 2002 6 case control studiescase control studies 0 Type of controls unexposed, sickunexposed, sick 1.87[0.44; 7.99]17480%NAVajda (Gabapentin) (Controls unexposed, sick), 2013 Mawer (Gabapentin) (Controls unexposed, sick), 2010 Morrow (Gabapentin) (Controls unexposed, sick), 2006 Dean (Gabapentin), 2002 4 exposed to other treatment, sickexposed to other treatment, sick 0.55[0.11; 2.79]1511440%NAThe NAAED (Gabapentin) (Epilepsy), 2025 Battino, 2024 2 Tags Adjustment   - No  - No 1.09[0.37; 3.21]1681920%NAThe NAAED (Gabapentin) (Epilepsy), 2025 Battino, 2024 Vajda (Gabapentin) (Controls unexposed, sick), 2013 Mawer (Gabapentin) (Controls unexposed, sick), 2010 Morrow (Gabapentin) (Controls unexposed, sick), 2006 Dean (Gabapentin), 2002 6 All studiesAll studies 1.09[0.37; 3.21]1681920%NAThe NAAED (Gabapentin) (Epilepsy), 2025 Battino, 2024 Vajda (Gabapentin) (Controls unexposed, sick), 2013 Mawer (Gabapentin) (Controls unexposed, sick), 2010 Morrow (Gabapentin) (Controls unexposed, sick), 2006 Dean (Gabapentin), 2002 60.150.01.0

Publication bias and p-hacking diagnosis

funnel plot
0.0-4.95.02.5250.000The NAAED (Gabapentin) (Epilepsy), 2025Battino, 2024Vajda (Gabapentin) (Controls unexposed, sick), 2013Mawer (Gabapentin) (Controls unexposed, sick), 2010Morrow (Gabapentin) (Controls unexposed, sick), 2006Dean (Gabapentin), 2002

Asymetry test p-value = 0.1834 (by Egger's regression)

slope=-2.6322 (1.7462); intercept=2.0748 (1.2913); t=1.6068; p=0.1834

p values plot
0.01.00.01.0

Sub-groups analysis using all included studies

excluded 6060, 8274, 8276, 6379

Sub-groupsTE95% CIn casesn exposedkI2ROB type of controls unexposed controls (disease free or unspecified)unexposed controls (disease free or unspecified) Out of scale14.28[0.53; 384.83]62 -NAMawer (Gabapentin) (Controls unexposed, disease free), 2010 1 unexposed, sick controlsunexposed, sick controls 1.87[0.44; 7.99]17480%NAVajda (Gabapentin) (Controls unexposed, sick), 2013 Mawer (Gabapentin) (Controls unexposed, sick), 2010 Morrow (Gabapentin) (Controls unexposed, sick), 2006 Dean (Gabapentin), 2002 4 exposed to other treatment, sick controlsexposed to other treatment, sick controls 0.86[0.29; 2.59]1881910%NAThe NAAED (Gabapentin) (Epilepsy), 2025 Battino, 2024 Vajda (Gabapentin) (Controls exposed to Lamotrigine, sick), 2013 Mawer (Gabapentin) (Controls exposed to Lamotrigine, sick), 2010 Morrow (Gabapentin) (Controls exposed to Lamotrigine, sick), 2006 50.510.01.0