Interpretation
In this population, approximately half of women with endometriosis were
asymptomatic of endometriosis and were diagnosed for the first time in
pregnancy. This is in agreement with previous studies which showed that
endometriosis is a relatively common finding in asymptomatic, fertile
women.22 In our study population, women with
endometriosis were more likely to have conceived using assisted
reproductive techniques. The proportion of women with a new diagnosis of
endometriosis that conceived following fertility treatment was similar
to that of women with known endometriosis. These findings support the
theory that women with difficulty conceiving or undergoing fertility
treatment are likely to have a higher prevalence of pelvic
endometriosis.4,23 In our study, the proportion of
pregnancies conceived following fertility treatment was high, which is
likely to reflect the high number of IVF treatment cycles performed in
the local central urban area.
Our study demonstrated that only 14% of women with ultrasound features
of endometriosis had evidence of endometrioma in the absence of deep
nodules. These findings support those of Exacoustos et al (2018) that
reported ovarian endometriomas as rarely isolated lesions, but commonly
associated with pouch of Douglas obliteration, pelvic adhesions and the
presence of endometriotic nodules.24 Our study showed
that 15% of women of East Asian origin had evidence of pelvic
endometriosis. This supports previous findings that moderate-to-severe
endometriosis is more common in women with East or South East Asian
ethnicity attending a tertiary referral centre.25
The relationship between adenomyosis and endometriosis has previously
been described in the literature. Naftalin et al (2012) found that women
with a previous or current diagnosis of endometriosis were significantly
more likely to have adenomyosis, with an odds ratio of 4.06 (95% CI:
2.25–7.33).13 Di Donato et al (2014) demonstrated a
21.8% prevalence of adenomyosis in women affected by
endometriosis.26 In our study of pregnant women with
endometriosis we did not find as strong an association with adenomyosis
as previously reported. However, women in our study population were much
younger (median age 33 vs 40 in the study by Naftalin et
al.)13 which could explain our finding of much lower
prevalence of adenomyosis in women with and without endometriosis.