Introduction
Methods
Study Design
Objectives and Assessments
Statistical Analysis
Compliance with Ethics Guidelines
Results
Patients
Characteristic | China (n = 546) | Russia (n = 307) | France (n = 154) | Total (N = 1007) |
---|---|---|---|---|
Mean age (years) on visit day (range) | 31.80 (18–41) | 30.28 (19–41) | 31.58 (18–41) | 31.30 (18–41) |
Mean BMI ± SD, kg/m2
| 21.37 ± 3.27 | 22.22 ± 4.01 | 22.23 ± 4.07 | 21.76 ± 3.66 |
Ethnicity (%) | ||||
Asian | 546 (100) | 0 | 4 (2.6) | 550 (54.6) |
Caucasian/white | 0 | 306 (99.7) | 124 (80.5) | 430 (42.7) |
Black/African American | 0 | 0 | 14 (9.1) | 14 (1.4) |
Other | 0 | 1 (0.3) | 12 (7.8) | 13 (1.3) |
Marital status, n/N (%) | ||||
Single | 80 (14.7) | 43 (14.0) | 52 (33.8) | 175 (17.4) |
Married | 450 (82.4) | 204 (66.4) | 47 (30.5) | 701 (69.6) |
Free union* | 14 (2.6) | 44 (14.3) | 47 (30.5) | 105 (10.4) |
Divorced/separated | 2 (0.4) | 15 (4.9) | 7 (4.5) | 24 (2.4) |
Widowed | 0 | 1 (0.3) | 1 (0.6) | 2 (0.2) |
Education level, n/N
†
(%) | ||||
Primary school | 20 (3.7) | 3 (1.0) | 0 | 23 (2.3) |
High school | 112 (20.6) | 2 (0.7) | 7 (4.5) | 121 (12.0) |
Vocational or professional school | 59 (10.8) | 39 (12.7) | 7 (4.5) | 105 (10.4) |
Polytechnic or equivalent (+2 years) | 38 (7.0) | 21 (6.8) | 31 (20.1) | 90 (8.9) |
University or business school (+4 to 5 years) | 316 (58.0) | 242 (78.8) | 109 (70.8) | 667 (66.3) |
Missing | 1 | 0 | 0 | 1 |
Smoking status, n/N (%) | ||||
Smoker | 12 (2.2) | 50 (16.3) | 45 (29.2) | 107 (10.6) |
Never smoker | 530 (97.1) | 200 (65.1) | 91 (59.1) | 821 (81.5) |
Ex-smoker | 4 (0.7) | 57 (18.6) | 18 (11.7) | 79 (7.8) |
Endometriosis type (%) | ||||
No endometriosis | 156 (29) | 88 (29) | 44 (29) | 288 (29) |
SUP, n
| 156 (29) | 88 (29) | 44 (29) | 288 (29) |
OMA, n
| 156 (29) | 88 (29) | 44 (29) | 288 (29) |
DIE, n
| 78 (14) | 43 (14) | 22 (14) | 143 (14) |
Primary Objective
Factors Associated with OMA or DIE
Factor | China | Russia | France | Overall |
---|---|---|---|---|
BMI on the day of visit (kg/m2) | ||||
≥18.5 to <22 | – | Ref | – | Ref |
<18.5 | – | 2.20 [1.11–4.37] | – | 1.45 [1.00–2.11] |
≥22 to <25 | – | 0.63 [0.35–1.14] | – | 0.86 [0.63–1.18] |
≥25 | – | 0.50 [0.26–0.97] | – | 0.65 [0.44–0.96] |
Marital status | ||||
Married | – | Ref | – | – |
Single | – | 4.84 [2.34–10.00] | – | – |
Free union females | – | 2.05 [1.06–3.96] | – | – |
Divorced or separated or widowed | – | 1.12 [0.39–3.22] | – | – |
Education level | ||||
University or business school | – | – | – | Ref |
Primary and high school | – | – | – | 0.60 [0.41–0.88] |
Vocational or professional school | – | – | – | 0.68 [0.44–1.04] |
Polytechnic or equivalent | – | – | – | 1.05 [0.68–1.63] |
Non-cyclic chronic pelvic pain | ||||
No | Ref | Ref | – | Ref |
Yes | 2.30 [1.40–3.78] | 5.20 [3.18–8.51] | – | 2.44 [1.84–3.23] |
Dysmenorrhea pain at intensities | ||||
0 | Ref | Ref | Ref | Ref |
≥1 to ≤4 | 2.77 [1.77–4.34] | 1.72 [0.71–4.14] | 6.50 [1.00–42.31] | 2.56 [1.76–3.73] |
≥5 to ≤7 | 3.31 [2.00–5.46] | 2.59 [1.37–4.88] | 1.67 [0.63–4.39] | 2.47 [1.74–3.50] |
≥8 to ≤10 | 6.96 [4.02–12.07] | 4.81 [2.63–8.81] | 4.95 [1.91–12.80] | 5.41 [3.79–7.72] |
Deep dyspareunia | ||||
No | Ref | Ref | – | Ref |
Yes | 3.09 [1.81–5.27] | 2.56 [1.61–4.07] | – | 2.05 [1.56–2.70] |
Pain at time of ovulation | ||||
No | – | Ref | – | Ref |
Yes | – | 1.77 [1.11–2.82] | – | 1.48 [1.09–2.01] |
GI symptoms during menstruation | ||||
No | Ref | Ref | – | Ref |
Yes | 3.40 [2.23–5.19] | 3.46 [2.15–5.55] | – | 2.70 [2.06–3.52] |
Urinary symptoms during menstruation | ||||
No | Ref | Ref | – | Ref |
Yes | 4.34 [1.91–9.85] | 2.17 [1.14–4.16] | – | 2.47 [1.60–3.81] |
Infertility | ||||
No | – | Ref | – | Ref |
Yes | – | 0.23 [0.14–0.37] | – | 0.56 [0.43–0.73] |
Previously surgical diagnosis | ||||
No | Ref | Ref | Ref | Ref |
Yes | 7.07 [3.10–16.14] | 8.47 [3.15–22.73] | 2.37 [1.05–5.37] | 4.92 [3.06–7.90] |
Hormonal treatment for endometriosis | ||||
No | Ref | Ref | Ref | Ref |
Yes | 22.32 [7.97–62.52] | 12.54 [5.68–27.71] | 2.64 [1.23–5.69] | 8.41 [5.39–13.12] |
Lifelong menstrual cycles | ||||
Always/generally regular | Ref | Ref | Ref | Ref |
Irregular | 0.37 [0.17–0.84] | 0.36 [0.17–0.76] | 0.23 [0.08–0.73] | 0.34 [0.21–0.55] |
Time since age at menarche | 1.47 [1.06–2.03] | – | – | – |
Progestin-only oral contraceptive | ||||
No | Ref | – | – | Ref |
Yes | 0.26 [0.07–0.90] | – | – | 0.39 [0.16–0.99] |
Previous uterine surgery | ||||
No | Ref | – | – | – |
Yes | 1.57 [1.03–2.39] | – | – | – |
Pregnancy | ||||
No | Ref | Ref | – | – |
Yes | 1.42 [1.00–2.02] | 0.60 [0.38–0.95] | – | – |
Breastfed | ||||
Yes | Ref | – | – | – |
No | 0.48 [0.26–0.88] | – | – | – |
Birth premature | ||||
No | – | – | – | Ref |
Yes | – | – | – | 1.70 [1.04–2.78] |
History of endometriosis in first-degree relatives | ||||
No | Ref | Ref | – | Ref |
Yes | 4.12 [1.10–15.39] | 2.76 [1.31–5.80] | – | 2.37 [1.38–4.08] |
Drinking alcohol | ||||
No | Ref | Ref | – | – |
Yes | 9.83 [1.02–95.06] | 0.08 [0.01–0.57] | – | – |
Number of fish consumed per week | – | – | 0.01 [0.00–0.40] | – |
Exercise done | ||||
No | – | – | Ref | – |
Yes | – | – | 0.45 [0.23–0.89] | – |
Health status | ||||
Excellent, very good, good | – | Ref | – | Ref |
Fair | – | 2.14 [1.33–3.43] | – | 1.62 [1.25–2.09] |
Poor | – | 1.82 [0.25–13.22] | – | 1.78 [0.90–3.53] |
Factor | China | Russia | France | Overall |
---|---|---|---|---|
Previous use of hormonal treatment for endometriosis | 17.95 [5.92–54.43] | 7.54 [2.90–19.57] | 3.04 [0.88–10.45] | 6.66 [4.05–10.93] |
Previous surgery for endometriosis | 3.06 [1.21–7.73] | 5.46 [1.46–20.38] | 1.05 [0.28–3.90] | 1.95 [1.11–3.43] |
Does not live in city or near a busy area | 2.14 [1.27–3.60] | NS | NS | 1.66 [1.09–2.52] |
GI symptoms during menstruation | 3.18 [1.90–5.31] | 3.85 [2.13–6.97] | NS | NS |
Lives or works in a busy area | NS | NS | NS | 1.66 [1.09–2.52] |
Infertility | 0.55 [0.34–0.87] | 0.19 [0.10–0.36] | 0.78 [0.38–1.63] | 0.46 [0.35–0.62] |
Irregular lifelong menstrual cycles | 0.36 [0.13–0.96] | NS | 0.19 [0.06–0.63] | NS |
Not breastfed | 0.33 [0.16–0.69] | NS | NS | NS |
Practice of vaginal douching | 0.39 [0.16–0.97] | NS | NS | 0.58 [0.35–0.98] |
Pregnancy | NS | 0.49 [0.27–0.91] | NS | NS |
Units of alcohol per week (10 u increase) | NS | 0.05 [0.00;0.67] | NS | NS |
Secondary Objectives—Overall Population
Secondary Objectives—Comparative Differences Between Regions
Gynecologic History
Factor | China | Russia | France | Statistical comparison between countries, Chi2 test (where applicable) | Total |
---|---|---|---|---|---|
Mean age of menarche [95% CI] | 13.60 [13.48–13.72] n = 545 | 12.96 [12.81–13.10] n = 307 | 12.68 [12.42–12.95] n = 154 | 13.26 [13.17–13.35] N = 1006 | |
Lifelong menstrual cycles, n/N (%) | |||||
Always regular | 344/545 (63.1) | 144/307 (46.9) | 129/154 (83.8) | F vs R, P < 0.0001 C vs F, P < 0.0001 C vs R, P < 0.0001 | 617/1006 (61.3) |
Generally regular | 166/545 (30.5) | 120/307 (39.1) | 2/154 (1.3) | 288/1006 (28.6) | |
Irregular | 35/545 (6.4) | 43/307 (14.0) | 23/154 (14.9) | 101/1006 (10.0) | |
Missing | 1 | 0 | 0 | 1 | |
Tampon used regularly during menstruation, n/N (%) | 77/545 (14.1) | 76/307 (24.8) | 94/154 (61.0) | F vs R, P < 0.0001 C vs F, P < 0.0001 C vs R, P = 0.0001 | 247/1006 (24.6) |
Vaginal douching practised regularly, n/N (%) | 38/545 (7.0) | 20/307 (6.5) | 32/154 (20.8) | F vs R, P < 0.0001 C vs F, P < 0.0001 C vs R, P = 0.7989 | 90/1006 (8.9) |
Menstrual and ovulatory disorders, n/N (%) | 45/545 (8.3) | 56/307 (18.2) | 89/154 (57.8) | F vs R, P < 0.0001 C vs F, P < 0.0001 C vs R, P < 0.0001 | 190/1006 (18.9) |
Contraception use, n/N (%) | 384/546 (70.3) | 239/307 (77.9) | 143/154 (92.9) | F vs R, P < 0.0001 C vs F, P < 0.0001 C vs R, P = 0.0175 | 766/1007 (76.1) |
Pregnancy, n/N (%) | 326/546 (59.7) | 137/307 (44.6) | 52/154 (33.8) | F vs R, P = 0.0254 C vs F, P < 0.0001 C vs R, P < 0.0001 | 515/1007 (51.1) |
Gestations | |||||
1 to 3, n/N (%) | 279/326 (85.6) | 124/137 (90.5) | 48/52 (92.3) | 451/515 (87.6) | |
4 to 8, n/N (%) | 47/326 (14.4) | 13/137 (9.5) | 4/52 (7.7) | 64/515 (12.4) | |
Gestations with delivery (parity) | |||||
1 to 3, n/N (%) | 221/326 (67.8) | 76/137 (55.5) | 30/52 (57.7) | 327/515 (63.5) | |
Gestations without delivery | |||||
1 to 3, n/N (%) | 246/326 (75.5) | 104/137 (75.9) | 27/52 (51.9) | 377/515 (73.2) | |
4 to 7, n/N (%) | 21/326 (6.4) | 7/137 (5.1) | 2/52 (3.8) | 30/515 (5.8) | |
Miscarriage, n/N (%) | 77/267 (28.8) | 34/111 (30.6) | 19/29 (65.5) | 130/407 (31.9) | |
Voluntary abortion, n/N (%) | 184/267 (68.9) | 54/111 (48.6) | 12/29 (41.4) | 250/407 (61.4) | |
Therapeutic abortion, n/N (%) | 21/267 (7.9) | 26/111 (23.4) | 0/29 | 47/407 (11.5) | |
Ectopic pregnancy, n/N (%) | 8/267 (3.0) | 18/111 (16.2) | 1/29 (3.4) | 27/407 (6.6) | |
Infertility, n/N (%) | 154/546 (28.2) | 197/307 (64.2) | 50/154 (32.5) | F vs R, P < 0.0001 C vs F, P = 0.3039 C vs R, P < 0.0001 | 401/1007 (39.8) |
Primary, n/N (%) | 85/154 (55.2) | 117/197 (59.4) | 32/50 (64.0) | 234/401 (58.4) | |
Secondary, n/N (%) | 69/154 (44.8) | 80/197 (40.6) | 18/50 (36.0) | 167/401 (41.6) |
Endometriosis History
Factor | China | Russia | France | Statistical comparison between countries, Chi2 test (where applicable) | Total |
---|---|---|---|---|---|
Laparoscopy/laparotomy, n
| 509/37
n = 546 | 306/1
n = 307 | 127/27
n = 154 | 942/65
N = 1007 | |
Reason for surgery, n/N (%) | |||||
Suspicion of endometriosis | 196/546 (35.9) | 82/307 (26.7) | 89/154 (57.8) | 367/1007 (36.4) | |
Other gynecologic indication* | 290/546 (53.1) | 151/307 (49.2) | 49/154 (31.8) | 490/1007 (48.7) | |
Previous uterine surgery, n/N (%) | 108/545 (19.8) | 39/307 (12.7) | 8/154 (5.2) | F vs R, P = 0.0120 C vs F, P < 0.0001 C vs R, P = 0.0083 | 155/1006 (15.4) |
Previously surgically diagnosed with endometriosis, n/N (%) | 47/479 (9.8) | 31/307 (10.1) | 30/154 (19.5) | F vs R, P = 0.0050 C vs F, P = 0.0014 C vs R, P = 0.8960 | 108/940 (11.5) |
Mean age first endometriosis symptoms (years [95% CI]) | 28.15 [27.37–28.93] n = 331 | 27.66 [26.92–28.39] n = 180 | 22.54 [20.65–24.43]†
n = 63 | 27.38 [26.82–27.94]
N = 574 | |
Mean time between first medical attention and visit day (years [95% CI]) | 1.81 [1.48–2.14]
n = 366 | 1.93 [1.53–2.33]
n = 190 | 3.67 [2.66–4.67]†
n = 63 | 2.04 [1.78–2.29]
N = 619 | |
Mean time between first medical attention and diagnosis (years [95% CI]) | 1.07 [0.28–1.85] N = 46 | 0.50 [0.10–0.90] N = 30 | 5.76 [3.69–7.83] N = 29 | 2.20 [1.42–2.98] N = 105 | |
Mean time between first endometriosis symptoms and first medical attention (years [95% CI]) | 2.13 [1.62–2.64] n = 330 | 0.78 [0.43–1.13] n = 180 | 5.06 [3.66–6.47]†
n = 63 | 2.03 [1.67–2.39] N = 573 | |
Previous hormonal treatment for endometriosis, n/N (%) | 64/497 (12.9) | 57/307 (18.6) | 36/154 (23.4) | F vs R, P = 0.2248 C vs F, P = 0.0016 C vs R, P = 0.0284 | 157/958 (16.4) |
History of endometriosis in a first-degree relative, n/N (%) | 12/546 (2.2) | 34/307 (11.1) | 13/153 (8.5) | F vs R, P = 0.3897 C vs F, P = 0.0002 C vs R, P < 0.0001 | 59/1006 (5.9) |
Pre-Surgery Symptoms
Factor | China | Russia | France | Statistical comparison between countries, Chi2 test (where applicable) | Total |
---|---|---|---|---|---|
Non-cyclic chronic pelvic pain, n/N (%) | 76/546 (13.9) | 129/307 (42.0) | 73/154 (47.4) | F vs R, P = 0.3574 C vs F, P < 0.0001 C vs R, P < 0.0001 | 278/1007 (27.6) |
Mean intensity out of 10 [95% CI] | 3.74 [3.28–4.20] n = 76 | 5.64 [5.24–6.04] n = 129 | 5.40 [4.94–5.86] n = 73 | 5.05 [4.78–5.32] N = 278 | |
Dysmenorrhea, n/N (%) | 308/546 (56.4) | 147/307 (47.9) | 120/154 (77.9) | F vs R, P = 0.3574 C vs F, P < 0.0001 C vs R, P = 0.0166 | 575/1007 (57.1) |
Primary, n/N (%) | 99/308 (32.1) | 112/147 (76.2) | 73/120 (60.8) | 284/575 (49.4) | |
Secondary, n/N (%) | 209/308 (67.9) | 35/147 (23.8) | 47/120 (39.2) | 291/575 (50.6) | |
Mean intensity out of 10 [95% CI] | 5.39 [5.10–5.67] n = 308 | 6.99 [6.59–7.39] n = 147 | 7.34 [7.03–7.65]* n = 120 | 6.21 [6.00–6.41] N = 575 | |
Dysmenorrhea impacting life, n/N (%) | 136/308 (44.2) | 95/147 (64.6) | 98/120 (81.7) | F vs R, P = 0.0020 C vs F, P < 0.0001 C vs R, P = 0.0002 | 329/575 (57.2) |
Use of oral contraceptive in dysmenorrhea, primary, n/N (%) | 4/99 (4.0) | 16/112 (14.3) | 33/73 (45.2) | 53/284 (18.7) | |
Use of oral contraceptive in dysmenorrhea, secondary, n/N (%) | 11/209 (5.3) | 11/35 (31.4) | 6/47 (12.8) | 28/291 (9.6) | |
Pain at time of ovulation, n/N (%) | 30/546 (5.5) | 119/307 (38.8) | 65/154 (42.2) | F vs R, P = 0.4761 C vs F, P < 0.0001 C vs R, P < 0.0001 | 214/1007 (21.3) |
Mean intensity out of 10 [95% CI] | 3.50 [2.72–4.28] n = 30 | 4.52 [4.13–4.91] n = 119 | 4.48 [3.96–5.00] n = 65 | 4.36 [4.08–4.65] N = 214 | |
Deep dyspareunia, n/N (%) | 69/545 (12.7) | 140/307 (45.6) | 86/154 (55.8) | F vs R, P = 0.0380 C vs F, P < 0.0001 C vs R, P < 0.0001 | 295/1006 (29.3) |
Mean intensity out of 10 [95% CI] | 3.91 [3.50–4.33] n = 68 | 4.71 [4.38–5.05] n = 140 | 5.50 [4.99–6.01] n = 86 | 4.76 [4.51–5.00] N = 294 | |
GI symptoms during menstruation, n/N (%) | 123/546 (22.5) | 144/307 (46.9) | 81/154 (52.6) | F vs R, P = 0.2488 C vs F, P < 0.0001 C vs R, P < 0.0001 | 348/1007 (34.6) |
Mean intensity out of 10 [95% CI] | 3.43 [3.08–3.77] n = 120 | 4.60 [4.19–5.02] n = 144 | 5.58 [5.09–6.07]* n = 79 | 4.42 [4.16–4.67] N = 343 | |
Urinary symptoms at menstruation, n/N (%) | 32/546 (5.9) | 44/307 (14.3) | 21/154 (13.6) | F vs R, P = 0.8395 C vs F, P = 0.0013 C vs R, P < 0.0001 | 97/1007 (9.6) |
Mean intensity out of 10 [95% CI] | 3.41 [2.69–4.13] n = 32 | 4.89 [4.09–5.68] n = 44 | 4.76 [3.60–5.92] n = 21 | 4.37 [3.87–4.87] N = 97 |