Obstetrics and Gynaecology
Endometriosis, Fibroids and PCOS
Endometriosis, adenomyosis, uterine fibroids and PCOS for MBBS, with Rotterdam criteria and letrozole ovulation induction, mapped to NMC codes OG26, OG29 and OG30.
MedNext Academy | 3 min read
Endometriosis, Fibroids and PCOS
Endometriosis, adenomyosis, uterine fibroids and PCOS for MBBS, with Rotterdam criteria and letrozole ovulation induction, mapped to NMC codes OG26, OG29 and OG30.
This chapter covers three common benign gynaecological conditions: endometriosis with adenomyosis, uterine fibroids and polycystic ovary syndrome. It explains their pathology and presentation, the diagnostic approach including laparoscopy and the Rotterdam criteria, and their medical and surgical management with attention to fertility and long-term risks.
High-yield: Endometriosis, Fibroids and PCOS
- Endometriosis is functioning endometrial tissue outside the uterus, classically causing cyclical pelvic pain, dysmenorrhoea, dyspareunia and infertility.
- The ovary is the commonest site of endometriosis, where it forms a chocolate cyst (endometrioma).
- Laparoscopy with visualisation of deposits is the gold standard for diagnosing endometriosis.
- Endometriosis is managed with analgesia, hormonal suppression such as combined pills or progestogens, and surgery for severe disease.
- Adenomyosis is endometrial tissue within the myometrium, causing a bulky, tender uterus with menorrhagia and dysmenorrhoea.
- Uterine fibroids (leiomyomas) are benign smooth muscle tumours and the commonest pelvic tumour in women.
- Fibroids are classified by location as submucosal, intramural and subserosal; submucosal ones most affect bleeding and fertility.
- Fibroids may cause menorrhagia, pressure symptoms, subfertility and, in pregnancy, red degeneration with pain.
- Symptomatic fibroids are managed medically or by myomectomy to preserve fertility, or hysterectomy when childbearing is complete.
- Polycystic ovary syndrome is diagnosed by the Rotterdam criteria requiring two of three: oligo-ovulation, hyperandrogenism and polycystic ovaries on ultrasound.
- PCOS features oligomenorrhoea, hirsutism, acne, obesity and insulin resistance, and is a leading cause of anovulatory infertility.
- Lifestyle and weight loss are first-line in PCOS; combined pills regulate cycles and treat hyperandrogenism.
- Metformin improves insulin resistance, and letrozole is the preferred agent for ovulation induction in PCOS.
- PCOS carries long-term risks of type 2 diabetes, metabolic syndrome and endometrial hyperplasia from unopposed oestrogen.
Three benign conditions compared
- **Endometriosis:** Ectopic endometrium; cyclical pain, dyspareunia, chocolate cyst; laparoscopy diagnostic.
- **Fibroids:** Benign smooth muscle tumours; menorrhagia, pressure; myomectomy or hysterectomy.
- **PCOS (Rotterdam):** Two of three: oligo-ovulation, hyperandrogenism, polycystic ovaries.
- **PCOS treatment:** Lifestyle first; combined pills, metformin; letrozole for ovulation.
NMC competencies in this chapter
- **OG25.2:** Anovulation and ovulatory dysfunction in gynaecological disease
- **OG26.1:** Endometriosis and adenomyosis
- **OG29.1:** Uterine fibroids
- **OG30.1:** PCOS: etiopathogenesis, diagnosis and investigations
- **OG30.2:** PCOS management and hyperandrogenism
Frequently Asked Questions
How is endometriosis diagnosed?
Laparoscopy with direct visualisation of endometriotic deposits is the gold standard. The typical history is cyclical pelvic pain, dysmenorrhoea, dyspareunia and subfertility.
How are uterine fibroids classified?
By location as submucosal, intramural and subserosal. Submucosal fibroids most affect menstrual bleeding and fertility, guiding the choice of treatment.
What are the Rotterdam criteria for PCOS?
A diagnosis needs two of three features: oligo-ovulation or anovulation, clinical or biochemical hyperandrogenism, and polycystic ovaries on ultrasound, after excluding other causes.
What is the preferred ovulation-induction agent in PCOS?
Letrozole, which has largely replaced clomifene as first-line for inducing ovulation in women with PCOS trying to conceive, alongside lifestyle measures and metformin.
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