Obstetrics Flashcards
(92 cards)
What are the normal pH ranges at delivery for uterine artery and vein samples during cord gases?
Uterine vein (reflects maternal status and placental function): pH 7.2 - 7.44)
Uterine artery (reflects fetal status): pH 7.1 - 7.38
What does the FIGO classification for abnormal uterine bleeding PALM-COEIN stand for?
P: Polyps
A: Adenomyosis
L: Leiomyoma (ie fibroids)
M: Malignancy (endometrial, cervical, ovarian)
C: Coagulopathy
O: Ovulatory dysfunction
E: Endometrial
I: Iatrogenic
N: Not yet classified
Is the luteal phase fixed at 14 days, true or false?
True. The lifespan of the corpus luteum is 14 days
Which age group has the highest variability in menstrual cycle length on average?
<25 year olds have the highest menstrual cycle length variability. Variability declines to be at the lowest in the 35-39 age category. Variability then slightly increases again in the 40-44 category.
Menstrual cycles tend to get shorter with age, true or false?
True.
What is the ‘normal’ menstrual blood loss per cycle?
25-50ml is considered normal. Menstrual blood loss equal or greater than 80ml is considered abnormal (HOWEVER when defining HMB clinically, impact on physical / emotional / quality of life is the definition. the use of >80ml per cycle should only be used for research work)
A 32-year-old woman presents with symptoms of menorrhagia, dysmenorrhoea and cyclical, localised pelvic pain. The pelvic ultrasound showed no abnormality. What is the next appropriate investigation?
Laparoscopy
Allows diagnosis +/- ablation therapy for endometriosis in younger females with cyclical pelvic pain + dysmennhorea + menorrhagia and a normal USS.
What 2 investigations are pre-requisities before performing uterine artery embolisation on fibroids?
1) Hysteroscopy
2) MRI pelvis
What is the first-line diagnostic tool for the identification of structural pathology in women with HMB?
Transvaginal / transabdominal USS
What is the next appropriate investigation for postmenopausal bleeding with abnormal endometrial thickness on USS?
Urgent outpatient hysteroscopy + endometrial biopsy
Which specific test, additional to routine screening, is undertaken on women with HMB in their teenage years or who have had HMB since menarche
Testing for coagulation disorders, including von willebrand’s disease
What are contraindications for endometrial ablation?
Endometrial ablation is lower risk (but has ~ 20% risk of inadequate resolution leading to eventual hysterectomy) than hysterectomy for those women that suffer with HMB resistant to medical treatment and that do not wish for further children. Contraindications to ablation are;
- Large uterus - either >12 weeks in size or >12 cm in length - not an absolute contraindication but the chance of success lower
- Submucosal fibroid/s >2cm
- Any non-benign endometrial pathology
- Cervical cancer
- Current pelvic infection
- If hysterectomy is required for another condition
What are the 4 features of a menstrual cycle that you should assess and what are the ‘normal’ (5th - 95th centile) values for them?
Frequency - should be between every 24-38 days
Variability - there should be max 7-9 days variability between the shortest and longest cycles
Duration - 4-8 days of bleeding per cycle
Volume - subjective, but 25-50ml considered normal, >80 is heavy
What are the different sub-divisions of intermenstrual bleeding (IMB)?
- Cyclic mid-cycle IMB - regular midcycle bleed that can be physiological due to the trough in oestrogen at the time of ovulation
- Cyclic pre or post menstrual IMB - bleeding that cyclically occurs either in the follicular phase or in the luteal phase
- Acyclic IMB - IMB that is not cyclical / predictable
Definition of infrequent periods?
Periods every >38 days
Definition of frequent periods?
Periods every 23 days or less
Definition of irregular periods?
10 or more days variation in menstrual cycle lengths
Definition of prolonged menses?
> 8 days bleeding per cycle
Acute versus chronic non-gestation AUB?
Acute is a one-off episode of abnormal uterine bleeding whereas chronic is an abnormality in frequency, variability, duration or volume that has been present for the majority of the last 6 months or more.
What are polyps?
Polyps = localised overgrowth of endometrial stroma and gland tissue. Can be endometrial or endocervical. Can be pedunculated or sessile (flat). Tend to be smaller than fibroids. Don’t tend to be painful. Can cause irregular periods + IMB / spotting.
What are the 3 layers of the uterine wall?
Endometrium, myometrium and perimetrium
What is adenomyosis? What are it’s presenting symptoms and what are the classical US findings?
Adenomyosis = growth of endometrial tissue within the myometrial layer. Tends to present with dysmennorhoea + menorrhagia and an enlarged, tender uterus.
TVUS shows a globular enlarged uterus, heterogenous echogenicity of the myometrium, loss of clarity of the endo-myometrial junction + linear striations.
What are known risk factors for adenomyosis?
Factors that disrupt the endo-myometrial junction (= ^ parity, prev LSCS, prev TOP, uterine curettage) and prolonged oestrogen exposure (advancing age, prev tamoxifen use)
SMOKING MAY BE PROTECTIVE
what are fibroids and how do they typically present?
Fibroids are benign smooth muscle tumours of the myometrium. They typically grow larger than polyps, are extremely common (>80% in black women + >70% in white women by age 50), result in prolonged + painful periods and chronic pelvic pain and pressure symptoms.
As women get older there is small but significant risk of malignant transformation of fibroids into leiomyosarcomas = uterine sarcomas arising within a fibroid and presenting with AUB and more rapid fibroid growth. Incidence of uterine sarcoma is essentially non-existent <45 and only ~0.5% in peri and post menopausal women.
