Table 2 Study characteristics of 11 studies about Vitamin supplementation impact on endometriosis-related pain

Nalini Santanam et al.,2013 [29]

Atlanta

RCT

(46/13)

19-41year

vitaminE1200IU + vitamin C1000mg for 8 weeks

placebo pills daily for 8 weeks

Intervention group patient with decreased pain (43%)

Control group patient with decreased pain (0%)

Intervention group patient with decreased pain (37%)

Control group patient with decreased pain (36%)

Intervention group patient with decreased pain (24%)

Control group patient with decreased pain(0%)

Ibrahim Abd El-Fadil Sehsah et al.;2022 [30]

Egypt

RCT

(50/50)

Intervention:

25.36 ± 3.75;

Control:

26.18 ± 4.24

vitamin E 1200mg/day and vitamin C 1000mg/day for 6–8 weeks

placebo for 6–8 weeks

Intervention group patient with decreased pain (48%)

Control group patient with decreased pain(10%)

Intervention group patient with decreased pain (48%)

Control group patient with decreased pain(10%)

Intervention group patient with decreased pain (32%)

Control group patient with decreased pain(8%)

Mahmoud A. Al-Naggar et al.;2022 [31]

Iran

RCT

(30/30)

Intervention:

32.5 ± 4.5

Control:

31.4 ± 5.2

vitaminE1200IU/day + 

Vitamin C 1000mg/day for 8 weeks

Placebo pills for

8 weeks

Intervention group patient with decreased pain (30%)

Control group patient with decreased pain(0%)

Intervention group patient with decreased pain(26.6%)

Control group patient with decreased pain(0%)

Intervention group patient with decreased pain (16.6%)

Control group patient with decreased pain(0%)

Leila Amini et al,2021 [32]

Iran

RCT

(30/30)

Intervention:

35.7 ± 5.71;

Control:

38.03 ± 6.47

vitaminE800IU + vitaminC1000mg for 8 weeks

placebo pills daily for 8 weeks

Intervention VAS score:

pre-post: (66.26 ± 27.84–

12.43 ± 13.28)

Control group VAS score

:pre-post: (16.96 ± 16.28–

18.63 ± 18.35);P < 0.001

Intervention VAS score:

pre-post: (50.53 ± 32.12–17.56 ± 16.65)

Control group VAS scorec:

pre-post: (51.00 ± 34.21–

31.56 ± 26.39);P < 0.001

Intervention VAS score

pre-post: (66.26 ± 28.27–

15.43 ± 18.47)

Control group VAS score:

pre-post: (20.73 ± 21.77–

18.10 ± 19.93);P < 0.001

HuiMing Wang 2017 [33]

China

RCT

(32/32)

Intervention:

37.9 ± 3.5;

Control:

35.0 ± 3.3

Yasmin + vitamin E 100mg/d for 6mo

Yasmin for 6mo

Intervention VAS score:

pre-post: 7.85 ± 2.17- 2.65 ± 0.81;

Control group VAS score:

pre-post:7.90 ± 1.19—4.35 ± 1.11

Intervention VAS score:

pre-post:6.75 ± 1.25–2.50 ± 1.00;

Control group VAS score:

pre-post:6.63 ± 1.27 –2.79 ± 1.21

Intervention VAS score:

pre-post: 7.73 ± 2.15–3.01 ± 1.11;

Control group VAS score:

pre-post:7.65 ± 1.20–3.13 ± 1.01

Xiao Jing et al. 2018 [34]

China

RCT

(30/30)

Intervention:

35.12 ± 3.2;

Control:

38.02 ± 4.01

Yasmin + vitamin E 100mg/d for 6mo

Yasmin for 6mo

Intervention VAS score:

pre-post:7.83 ± 2.16–2.66 ± 0.82;

Control group VAS score:

pre-post: 7.81 ± 0.82–4.33 ± 1.10

Intervention VAS score:

pre-post:6.77 ± 1.24–2.51 ± 1.02;

Control group VAS score:

pre-post: 6.62 ± 1.28–2.80 ± 1.20

Intervention VAS score:

pre-post:7.72 ± 2.14–3.00 ± 1.12;

Control group VAS score:

pre-post: 7.66 ± 1.21–3.12 ± 1.02

Hu Yan et al. 2015 [35]

China

RCT

(26/25)

Intervention: 32.45 ± 6.18; Control:

34.62 ± 5.47

Yasmin + vitamin E 100mg/d for 6mo

Yasmin for 6mo

Intervention VAS score:

pre-post:74.05(16.17)-30.14(15.29);

Control group VAS score:

pre-post:76.11(17.84)-51.37(13.54)

Intervention VAS score:

pre-post:77.27(16.46) –42.33(10.15);

Control group VAS score:

pre-post:75.28(16.54)–44.08(12.80)

Intervention VAS score:

pre-post:68.36(19.08)-50.41(13.78);

Control group VAS score:

pre-post:65.61(17.14)-49.24(12.63)

Fariba Almassinokiani et al.; 2016 [23]

Iran

RCT

(19/19)

Intervention:30.84 ± 5.79

Control:

28.95 ± 4.71

vitamin D 3(50 000 IU weekly for 12 weeks

placebo for 12 weeks

Intervention VAS score:

pre-post:4.05 (3.45)–0.84 (1.74);

Control group VAS score:

pre-post: 4.82 (4.1) –0.68 (1.70)

Intervention VAS score:

pre-post: 7.37 (2.61)–2.10 (2.33);

Control group VAS score:

pre-post:6.42 (3.04)–2.73 (2.84)

Abolfazl Mehdizadehkashi et al.;2021 [24]

Germany

RCT

(25/25)

Intervention:

34.8 ± 7.1;

Control:

35.6 ± 7.0

50,000 IU vitamin D every 2 weeks for 12 weeks

placebo for 12 weeks

Intervention VAS score:

pre-post: (8.0 ± 1.8–

4.8 ± 1.7)

Control group VAS score:

pre-post: ( 6.8 ± 2.6– 4.9 ± 2.8);

Intervention VAS score:

pre-post: ( 6.1 ± 2.6–3.8 ± 2.3)

Control group VAS score:

pre-post: (7.3 ± 2.5– 5.2 ± 2.6);

James L Nodler et al.; 2020 [36]

America

RCT

(27/20)

Intervention:

20.0 ± 2.7;

Control:

20.1 ± 3.5

2000 IU vitamin D3 for 6mo

placebo for 6 mo

Intervention VAS score:

pre-post:7.0 (2.2)–

5.5(3.1);

Control group VAS score:

pre-post 6.0 (1.9)- 4.4 (3.1)