Illicit Cannabis Usage as a Management Strategy in New Zealand Women with Endometriosis: An Online Survey

Abstract

Background:

Endometriosis affects around 10% of women worldwide. Many women with endometriosis struggle with finding adequate pain management, and data from other countries suggest that women use cannabis, either legal or illicit, to help manage their endometriosis symptoms. The aim of this study was to determine use of cannabis where endometriosis was self-identified as a condition that was being treated with cannabis, as well as the impact of cannabis use on the usage on other pharmaceuticals.

Materials and Methods:

A cross-sectional online survey of those using cannabis for health-related conditions run between May and July 2019. This article reports on the subset of this larger data set for those reporting they had a diagnosis of endometriosis and/or polycystic ovary syndrome. Data were collected on demographics, modes of cannabis administration, symptoms treated, changes in pharmaceutical usage, and adverse events.

Results:

Two hundred thirteen valid responses were analyzed. Mean age of respondents was 32 years and 79.8% were current cannabis users. The most common outcomes that cannabis was used for were to improve pain relief (95.5%) and to improve sleep (95.5%). Respondents reported that their symptom was “much better” for pain (81%), sleep (79%), and nausea or vomiting (61%). Over three-quarters (81.4%) indicated cannabis had reduced their normal medication usage. Over half (59%) were able to completely stop a medication, most commonly (66%) analgesics. Opioids (40%) were the most common class of analgesic stopped.

Conclusions:

Cannabis is reported as an effective intervention for pain and other endometriosis symptoms with potential substitution effects on opioid usage.

Introduction

Endometriosis is an estrogen-dependent, chronic, inflammatory disease characterized by the presence of lesions containing endometrial-like tissue outside the uterus.^1,2 The estimates of prevalence worldwide suggest endometriosis occurs in 5%–10% of reproductive-age females.^3,4 In recent Australian data, one in nine women were diagnosed with endometriosis by the age of 40–44 (prevalence rate of 11%).⁵

Symptom presentation in endometriosis is heterogenous, but most commonly includes severe dysmenorrhea (period pain), noncyclic pelvic pain, and infertility.⁶ Other symptoms include bloating, dyspareunia (painful sex), dyschezia (pain on defecation), dysuria (painful urination),⁷ fatigue,⁸ and gastrointestinal issues often similar to irritable bowel syndrome (IBS).⁹ Alongside the reduction in overall quality of life,¹⁰ endometriosis impacts women's well-being and health, including mental and emotional health,¹¹ sexual/intimate relationships,¹² and social activities.¹⁰

Both surgical and pharmaceutical treatments are commonly used for endometriosis, with surgery showing benefits for pain, at least in the short to medium term.¹³ Current pharmaceutical treatments for endometriosis include the use of the oral contraceptives or progestogens and nonsteroidal anti-inflammatory drugs (NSAIDs). Effectiveness for pain control is variable among individuals and for some interventions (such as NSAIDs) is inconclusive.¹⁴ In addition, for some treatments that are effective for pain, such as gonadotropin-releasing hormone (GnRH) analogues, the side effects are problematic for many women, and discontinuation rates are high.¹⁵ While we do not have New Zealand data, in the United States, opioids are commonly prescribed for women with endometriosis¹⁶; in Australia, common opioids such as oxycodone and codeine carry an increased risk of dependency and overdose.¹⁷

These factors are likely, at least in part, to explain why 76% of Australian women report self-management of endometriosis symptoms.¹⁸ Australian data suggest that around 1 in 10 of the women who used self-management strategies had tried cannabis, most likely from illicit sources, to manage their pain and other symptoms; 56% of these women report a subsequent significant reduction in pharmaceutical medication use related to endometriosis.¹⁹

Recreational cannabis use was illegal in New Zealand at the time of the survey and access to cannabis for therapeutic purposes was limited. A small number of cannabis-based pharmaceutical medicines were available by prescription, including Sativex, as well as a limited number of cannabidiol products containing <2% tetrahydrocannabinol (THC). Despite the illegality, we hypothesized that, similar to Australia,¹⁹ cannabis use would not be uncommon in endometriosis patients in New Zealand and that their use of cannabis would impact on their use of prescribed pain and other medications.

The aim of this survey was to explore New Zealanders' use of cannabis where endometriosis was self-identified as a condition that was being treated with cannabis, as well as the impact of cannabis use on the usage on other pharmaceuticals.

Materials and Methods

Study population

We surveyed a convenience sample of people in New Zealand self-reporting therapeutic use of cannabis or a cannabis-based medicine through the administration of a cross-sectional online survey. A cannabis-based medicine may have been formally prescribed as a pharmaceutical product or “natural” or “raw” cannabis may have been used in any form (e.g., flowers, edible, oil, tincture). Eligibility criteria included participants being 18+ years, having used or currently using cannabis therapeutically, and being able to provide informed consent. This article only reports on people who indicated they had a diagnosis of endometriosis and/or polycystic ovary syndrome (PCOS). Proof of a formal diagnosis (e.g., laparoscopy or ultrasound scan) was not required.

Survey design and hosting

Accessing the survey required prospective participants to acknowledge reading and understanding the participant information sheet and then consenting via a link. The survey was run for 3 months (May to July 2019), linked to a medicinal cannabis patient advocacy Facebook group, and subsequently promoted through online cannabis and patient fora, consumer groups, and patient-specific and professional networks. Data were collected and managed through SurveyMonkey, a secure web-based platform compliant with the US HIPAA standard for medical systems. No personal data were logged and only the researchers had access to the raw data via two-factor authentication.

The survey questionnaire drew on a previously published Australian online survey²⁰ and was adapted to reflect New Zealand conditions. The views of consumer advisors, focus groups, clinicians, and researchers were sought to refine the questionnaire, with the following areas of interest identified:

Participant demographics;

cannabis use in relation to current treatment, including discussion with health professionals;

use patterns, including current and lifetime; dosage, frequency, and time of use; form of cannabis and route of administration; changes in use over time;

efficacy, including negative effects and comparisons with other medicines, incorporating items from the Patient Global Impression of Change.²¹

This article reports on demographics, use, efficacy, and side effects of cannabis, and comparison with, and where relevant, any substitution of current medications taken. The study was approved by the New Zealand National Health and Disability Ethics Committees (HDEC; reference: 19/CEN/54).

Analyses

Data were analyzed using SPSS v26 (IBM Corporation, Chicago, IL). Descriptive statistics were presented as means and standard deviations (for normally distributed data), medians and interquartile ranges (for non-normally distributed data), or numbers and percentages (for categorical data). Missing data were reported and not replaced. Individual medications were classified into categories (e.g., NSAIDs) by a medical doctor (E.H.).

Results

The data reported here are a subset of a larger data set examining the therapeutic use of cannabis and cannabis-based medicines in New Zealanders across multiple self-identified conditions. Eligible responses were received from 213 participants, this being 10% of the total respondent sample (n = 2125). The mean age of respondents with endometriosis and/or PCOS was 32 (±9) years, with the Auckland (19.7%) and Canterbury (18.8%) regions having the most respondents (Table 1). Most respondents identified as NZ European (84.1%) and were working (55.8%); however, a substantial minority (36.6%) were unemployed. Most respondents report having endometriosis and/or PCOS symptoms for at least 5 years (73.7%).

Table 1.

Demographics

n = 213
Age
Mean (SD)		32.3 (9.8)
	N	%
18–25	67	31.5
26–35	79	37.1
36–45	46	21.6
46–55	17	8.0
56+	4	1.9
Did not answer	2	0.9
Gender
Female	209	98.1
Other	3	1.4
Transgender	1	0.5
Regions of New Zealand
Northland region	10	4.7
Auckland region	42	19.7
Waikato region	22	10.3
Bay of Plenty region	21	9.9
Gisborne region	2	0.9
Hawke's Bay region	5	2.3
Taranaki region	6	2.8
Manawatu-Wanganui region	18	8.5
Wellington region	13	6.1
Tasman region	3	1.4
Nelson region	6	2.8
Marlborough region	4	1.9
West Coast region	6	2.8
Canterbury region	40	18.8
Otago region	12	5.6
Southland region	3	1.4
Ethnicity^a
NZ European	180	84.1
Māori	51	23.9
Chinese	2	0.9
Indian	3	1.4
Samoan	0	0.0
Tongan	0	0.0
Niuean	0	0.0
Other	29	13.6
Total household income
Zero income	7	3.3
$1–$5,000	4	1.9
$5,001–$10,000	7	3.3
$10,001–$15,000	9	4.2
$15,001–$20,000	11	5.2
$20,001–$25,000	9	4.2
$25,001–$30,000	15	7.0
$30,001–$35,000	8	3.8
$35,001–$40,000	12	5.6
$40,001–$50,000	18	8.5
$50,001–$60,000	20	9.4
$60,001–$70,000	17	8.0
$70,001–$100,000	27	12.7
$100,001–$150,000	15	7.0
$150,001 or more	4	1.9
Don't know	13	6.1
I would rather not say	17	8.0
Employment status
Working full-time, 30+ hours or more a week	73	34.3
Working part-time	25	11.7
Working part-time, receiving a supported living payment	5	2.3
Working part-time, receiving ACC earnings-related compensation	1	0.5
Working part-time, receiving another benefit	15	7.0
Unemployed	18	8.5
Unemployed, receiving supported living payment	25	11.7
Unemployed, receiving ACC earnings-related compensation	6	2.8
Unemployed, receiving other benefits	29	13.6
Student	14	6.6
Retired	2	0.9
Duration of having endometriosis and/or polycystic ovarian syndrome
0–6 months	1	0.5
6–12 months	4	1.9
1–2 years	11	5.2
2–5 years	33	15.5
5–10 years	52	24.4
10–20 years	58	27.2
20+ years	47	22.1
Missing	7	3.3

Multiple options allowed.

ACC, accident compensation corporation; SD, standard deviation.

Most respondents were current cannabis users (79.8%) for medical purposes (Table 2). All respondents with endometriosis and/or PCOS had at least one comorbidity, most commonly depression and/or anxiety (80%), migraine headaches (46%), persistent nausea (42%), or lower back pain (41%). The most common symptoms that cannabis was used for were pain relief (95.5%), improving sleep (95.5%), increasing the ability to cope (80%), and nausea and vomiting (78.5%). Respondents reported a median score of 90 (80–100) to the question “How does (or did) cannabis affect your conditions or symptoms overall?” where 0 was no relief and 100 was excellent relief. Of the most common individual symptoms, respondents reported that their symptom was “much better” for pain (81%), sleep (79%), and nausea or vomiting (61%). Very few reported their symptom was worse or much worse (Supplementary Table S1).

Table 2.

Cannabis Usage Characteristics

n = 213
	Mean (SD)
Age when first started using cannabis for medicinal purposes?	22.7 (7.6)
Are you still using cannabis for any medical condition(s)?	n	%
Yes	170	79.8
No—It didn't work	0	0.0
No—I was unable to find a regular supply	9	4.2
No—It stopped working	0	0.0
No—I didn't like the side effects	6	2.8
No—I could not afford it	6	2.8
No—Because of its illegal status	9	4.2
Other	6	2.8
Did not answer	7	3.3
In what forms have you tried cannabis for medicinal reasons?^a
Eaten as a cooked recipe (biscuits, cookies, etc.)	140	65.7
Eaten as an oil-filled capsule	55	25.8
Consumed as a liquid (oil or tincture)	79	37.1
Drunk as a tea	31	14.6
Smoked as a cigarette (joint)	171	80.3
Smoked through a dry pipe (chillum)	135	63.4
Smoked through a water pipe (bong)	145	68.1
Inhaled through a vaporizer	86	40.4
Eaten as leaf/flower matter	29	13.6
Consumed raw blended into drinks (smoothie)	20	9.4
Used in a balm on the skin	93	43.7
Other	13	6.1
What form of administration has helped you the most with your condition? (n = 177)
Eaten as a cooked recipe (biscuits, cookies, etc.)	24	13.6
Eaten as an oil-filled capsule	5	2.8
Consumed as a liquid (oil or tincture)	17	9.6
Drunk as a tea	3	1.7
Smoked as a cigarette (joint)	51	28.8
Smoked through a dry pipe (chillum)	17	9.6
Smoked through a water pipe (bong)	38	21.5
Inhaled through a vaporizer	14	7.9
Eaten as leaf/flower matter	0	0.0
Consumed raw blended into drinks (smoothie)	0	0.0
Used in a balm on the skin	2	1.1
Other	6	3.4
How frequently do you or did you use cannabis in your usual form of cannabis? (n = 177)
Once a day	28	15.8
2–3 times day	56	31.6
4–5 times a day	24	13.6
Six or more times a day	16	9.0
1–2 times a week	18	10.2
3–5 times a week	19	10.7
Less than weekly	11	6.2
Very rarely	5	2.8

Multiple options allowed.

Respondents had tried a wide range of administration methods (Table 2) and the majority (67.8%) reported that inhaled forms of cannabis were the most effective. The most common time period for using cannabis was after 6 pm (50.4%). Most had been using cannabis for at least 2 years (75.6%), with a substantial proportion being users of more than 10 years (29.6%). Most current cannabis users reported that the amount of cannabis use varied depending on their condition (45%), or that there had been no change in the amount since they first started (17%), but around one in five users (21%) reported they had to use more cannabis over time. The use of vaporizers was low, with less than a quarter of respondents (23%) reporting owning one, while 12% reported they intended to purchase one. The most common reason for lack of a vaporizer was cost (26%). If a general practitioner (GP) or a pharmacy provided a vaporizer, then almost all respondents (93%) would use one.

Of the respondents, 176 (81.4%) indicated that cannabis had changed their normal medication usage; 128 (59%) were able to completely stop a medication, 97 (45%) were able to reduce a medication by at least half of the total dose, and 41 (19%) were able to reduce a medication but by less than half of the total dose (Table 3). Of the medications that were completely stopped, 66% were considered to be analgesics. The most common class of medication stopped was opioids (40%), followed by NSAIDs (17%), antidepressants (16%), and benzodiazepines (15%). Similar trends were seen in medication reduction where opiates (33%) and NSAIDs (16%) were the most common classes of medication reduced by at least half. Paracetamol was the most common medication (41%) that was able to be reduced by less than half. Only two respondents reported using metformin, consistent with our assumption that most respondents were using cannabis for endometriosis rather than PCOS symptoms.

Table 3.

Cannabis Usage and Medication

n = 178
	n	%
If you experience any undesirable effects from cannabis, how does this compare with any undesirable effects from your usual medication?
Much better	60	28.2
Somewhat better	25	11.7
No effect	7	3.3
Somewhat worse	5	2.3
Much worse	0	0.0
I have no undesirable effects from cannabis	74	34.7
I have no undesirable effects from my usual medication	5	2.3
I have not tried any/many other medications	2	0.9
Overall, how does (or did) cannabis compare with your other medicines in giving you relief from your condition?
Other medicines work much better than cannabis	0	0.0
Other medicines work a bit better than cannabis	8	3.8
Other medicines work about the same as cannabis	15	7.0
Cannabis works a bit better than other medicines	22	10.3
Cannabis works much better than other medicines	84	39.4
Only cannabis gives me relief from my condition	49	23.0

Discussion

This survey data demonstrate that cannabis was being used by endometriosis sufferers in New Zealand, despite illegalities at the time of the survey. Cannabis, most commonly inhaled via a pipe, joint, or bong, was considered by our respondents with endometriosis and/or PCOS to be very effective for the management of their symptoms especially in regard to pain, sleep, and gastrointestinal symptoms. The use of cannabis also allowed respondents to cease or reduce their usage of other medications, particularly opiate and NSAID analgesics.

A key strength to this study is that our respondents were fairly representative of New Zealand demographics based on recent census²² and government data,²³ with some notable exceptions. Respondents in 14 of the 16 regions were within 5% of the estimated 2019 population of that region,²⁴ with Auckland underrepresented (19.7% in our sample and 33.4% in the wider population) and Canterbury overrepresented (18.8% in our sample and 12.8% in the wider population). Participants identifying as New Zealand European and/or Māori are overrepresented in the sample in comparison with the New Zealand population 2018 census data (84.1% vs. 70.2%, and 23.9% vs. 16.5%, in our sample, and in the wider population, respectively).²²

While the Māori are more likely to have used cannabis medicinally than the non-Māori, their recreational use is significantly greater than therapeutic use.²⁵ The greater magnitude of recreational use for Māori is also noted in recent government data,²⁶ twice that (32% vs. 15.5%) of non-Māori, and even more pronounced when comparing Māori women with non-Māori women (odds ratio [OR] 2.46). Thus, while Māori comprise 23.9% of the present sample, this is less than what would be anticipated for recreational use. Finally, respondents had a slightly higher unemployment rate, with 56% of our respondents working compared with 63% of New Zealand women.²⁷ This may reflect the negative impact that endometriosis often has on employment.^10,28 This assumption is supported by the fact that our sample of medicinal users has a much lower employment rate than recreational cannabis users (67.4%) in New Zealand.²⁵

There were important limitations. First, all data, including diagnosis, was self-reported, and therefore, it is possible that those without a confirmed diagnosis of endometriosis may be included. All benefits and harms were likewise self-reported and it is possible that those who had negative experience with cannabis may not have answered this survey, given it was promoted via a cannabis patient advocacy group. These findings thus may not be extrapolated to wider populations. Second, the survey asked participants whether they had PCOS and/or endometriosis in a single question and it was, therefore, not possible to guarantee that all individuals examined in the current study had endometriosis. However, considering pain or nausea, the two-most commonly treated symptoms are not symptoms of PCOS²⁹ but are of endometriosis^6,9 and that only two people indicated they were using metformin (a key medication in the management of PCOS³⁰), suggesting that the majority of people in this sample were likely experiencing endometriosis-related symptoms.

Substantial evidence already exists for the use of cannabis or cannabinoids in other chronic pain conditions.^31
–33 Cannabis was reported to significantly improve pain, sleep, and nausea and vomiting in people with endometriosis in both New Zealand and in our previous work in Australia.¹⁹ Similar to our previous study on Australian women with endometriosis,¹⁹ cannabis was being used despite a lack of access to legal, medicinal cannabis. Most respondents were regular users whose use depended on their symptoms, with almost a third being long-term users of more than 10 years. Self-reported side effects, especially in comparison with their current medications, were low, with a third of users reporting no side effects at all. However, a small number of previous users indicated that undesirable side effects led to their cessation of cannabis usage. The number of comorbid symptoms in our respondents is not unusual, as depression, anxiety, chronic fatigue syndrome, IBS, and migraines are common, with around 95% of all women diagnosed with endometriosis experiencing at least one comorbidity.³⁴

Respondents reported clear evidence of a substitution effect, where the use of cannabis reduced or replaced other pharmaceutical medications,¹⁶ especially with respect to opioid-based analgesics, and also to other medications commonly used in the management of endometriosis-related symptoms,¹⁶ such as antidepressants, benzodiazepines, and NSAIDs. The preferred administration route in both populations was inhalation (inclusive of smoked and vaporized forms), with 67.8% of New Zealand and 61.9% of Australian respondents utilizing this method of administration.

These findings are consistent with outcomes from other studies conducted in Australia and internationally.^20,35 Whether this is due to lack of sophistication in administration methods in illicit markets, or perhaps consequent upon a more rapid onset of effect commonly observed via inhaled routes, is currently unknown.³⁶

Emerging evidence of the substitution effect of cannabis is increasing in the scientific literature^37

–40 and reports of deprescribing trends are common, particularly for drugs of the opioid class^34,41 similar to the findings in the current survey. The reduction in pharmaceutical medications by our respondents, with 59% reporting being able to cease a medication and 45% being able to reduce medication by at least 50%, reflects similar trends to our previous study on cannabis usage in Australian women. In the Australian study,¹⁹ 56% of the cannabis-using cohort self-reported significant reductions (defined as 50% or more reduction) in pharmaceutical medication use.

There were also similarities between the New Zealand cohort and Canadian data on patients using medicinal cannabis.⁴¹ Canadian patients self-reported substituting opioids with cannabis (35%), with 59% reporting total cessation of opioid use and 18% reducing opioid use by 75%⁴¹; further substitutions of cannabis were reported for antidepressants (21%), nonopioid pain medications (10%), and benzodiazepines (4%). Similar substitution effects were also observed in an earlier survey of patients registered to purchase medicinal cannabis from a Canadian Licensed Producer, with cannabis being substituted for opioids (32%), benzodiazepines (16%), and antidepressants (12%).³⁴

There are some differences apparent in this population compared with those previously studied. Total oral consumption of cannabis (oils, edible, etc.) was notably higher in the New Zealand data (27.7%) compared with Australian (11.9%). Cannabis use was more frequent in the New Zealand sample, with 70% of New Zealand respondents reporting cannabis use daily or multiple times per day compared with 43.7% of Australian respondents. In addition, a higher proportion of Australian women (25%) reported requiring cannabis less than once per week compared with those from New Zealand (6.2%).

Understanding the relative risks and/or benefits of these substitutions is complex, particularly as our data demonstrate that the type and dosage of cannabis used, and the route of application, vary widely in the community. Opioids account for over 30 unintentional overdose deaths per annum reported in New Zealand,⁴² with risks exacerbated where opioids are combined with benzodiazepines.⁴³ There is no doubt that improved pain relief options are needed for endometriosis patients.⁴⁴

Various phytochemicals (mainly cannabinoids) from Cannabis spp. have well-described analgesic, anti-inflammatory, anxiolytic, antidepressant, and antiemetic actions^{31,45

–49} and provide a plausible mechanism of action for the improvement of these symptoms via the endocannabinoid system (ECS) and other receptor types.⁵⁰ Our understanding of the mechanisms associated with endometriosis pain is still limited,⁵¹ and the effectiveness of different pharmaceutical analgesics and hormonal methods of pain control is highly variable¹⁴ with high discontinuation rates.¹⁵

In light of these well-known risks and side effects of current analgesics, it is easy to understand why cannabis may be considered a panacea for the management of endometriosis symptoms. However, cannabis usage is not without risks. General areas of concern include early initiation of use, that is, before age 18, being associated with mental ill-health, particularly in vulnerable populations^52,53; dependence,⁵⁴ including heightened risk with higher potency cannabis.⁵⁵ There are also risks associated with driving and operating machinery while impaired, described as mild to moderate,⁵⁶ although increasing with dose⁵⁷ and more so in combination with alcohol.⁵⁸ While concerns are commonly raised concerning cannabis inhalation, including pulmonary and bronchial problems, particularly associated with intensity of use, these may be reversible following cessation.⁵⁹ Interestingly, however, findings are more equivocal for other respiratory diseases, including lung cancer,⁶⁰ with confounding effects of tobacco use being problematic.⁶¹

Recognizing that cannabis use, including for therapeutic purposes, is unlikely to diminish, a recent review has proposed lower risk cannabis use guidelines and recommendations.⁶² These recommendations range from abstinence where possible to delayed initiation of use, use of lower potency products, lower intensity, and frequency of use. It is also suggested that combusted cannabis inhalation is avoided in favor of edibles and vaporizers, with evidence showing improvements in acute symptoms with their use,⁶³ although currently, evidence based on long-term studies is lacking.⁶⁴

Conclusions

Cannabis, both medical and illicit, is being used in New Zealand and internationally as a self-management tool and is reported to effectively relieve symptoms of endometriosis, including pain, sleep, and nausea. Cannabis appears to be preferred by respondents in this series to other pharmaceuticals such as opioids. Self-reported community data, such as these, add to the growing body of evidence that medicinal cannabis may be a potentially effective part of a multidisciplinary toolkit to manage the symptoms of endometriosis and support reduction of other classes of medication, including opioids. However, well-designed, blinded randomized trials are needed to determine the short- and long-term safety and effectiveness of various dosages and modes of administration of legally available cannabis.

Footnotes

Acknowledgments

We wish to acknowledge those participating in the online survey, many of whom provided information on activities that at the time of the survey were illegal.

We acknowledge the support of Medicinal Cannabis Awareness New Zealand (MCANZ) and particularly its coordinator at the time of the survey, Mr. Shane Le Brun.

Availability of Data and Materials

The data sets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.

Authors' Contributions

All authors contributed significantly to this work. M.A., J.S., G.N., J.G., D.B., and N.J. conceptualized the study. G.N. designed the survey and performed the data collection. G.N and M.A cleaned the data. M.A., M.L., and M.A.A.-D. performed the statistical analysis. M.A., J.S., N.J., E.H., and J.G. assisted with data interpretation. M.A. and J.S. drafted the article. G.N., M.L., J.G., E.H., D.B., N.J., and M.A.A.-D. contributed to critical revisions on the articles. All authors reviewed the article and approved the final draft.

Ethics Approval and Consent to Participate

The study was approved by the New Zealand National Health and Disability Ethics Committees (HDEC; reference: 19/CEN/54). Consent was by online access only, with participants being required to acknowledge they were 18 years or older, that they had read and understood the participant information sheet, before accessing the online questionnaire itself, and that they were able to provide informed consent.

Author Disclosure Statement

G.N. received funding from Medicinal Cannabis Awareness New Zealand (MCANZ), a not-for-profit registered charitable trust and medicinal cannabis patient advocacy group. M.A., M.A.A.-D., and J.S. as a medical research institute, NICM Health Research Institute receives research grants and donations from foundations, universities, government agencies, and industry. Sponsors and donors provide untied and tied funding for work to advance the vision and mission of the institute. This study was not specifically supported by donor or sponsor funding to NICM. M.A. is a member of the clinical advisory board for Endometriosis Australia and ESIG member for Endometriosis NZ.

Funding Information

No funding was received for this article.

Supplementary Material

Supplementary Table S1

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