Vaginal Delivery Flashcards
What is the surface area of the vagina mucosa?
90 cm²
How can the cells of the vaginal mucosa be described?
Stratified squamous and non-keratinised
Is the vagina mucosa epithelium vascularised?
No
What are characteristics of the lamina propria?
Loose
Highly vascularised
What hormone reduces vaginal mucosa thickness?
Progesterone
What is the sequence of the vagina blood supply?
Common iliac artery> internal iliac artery> vagina arteries
What is the sequence of vaginal blood drainage?
Vaginal Venus plexus> vaginal veins> internal iliac veins
(Bypasses liver and FPM)
How is drug transported in the vagina?
Drug is administered to vagina
Drug enters veins
Drug enters the arteries ( uterine )
Arteries deposit drug and uterus
What is vaginal fluid made from and how much is produced daily?
Vagina mucus
Cervical mucus
Menstruation fluid
Endometrial fluid
6 g
What is a healthy vagina pH and how is this maintained?
3.5 to 5
Lactobacillus
When does the vagina pH rise?
During menstruation
Sex
Infection
What are advantages of vagina delivery?
Accessible
Non-invasive
Nonparental
Highly perfused
Avoids first past metabolism
Local or systemic effect
What are disadvantages of vagina delivery?
Cultural
Hygiene
Messy for semisolids
Poor compliance
Tissue permeability is influenced by oestrogen and fluctuations affect pharmacokinetics for systemic drugs
When would vaginal delivery be used?
For women’s healthcare
Spermicidal contraception
Labour induction
Oestrogen replacement
Vagina infections
Treat cervical vaginal cancer
What are characteristics of vaginal rings?
Passive diffusion controlled
One or more drugs controlled overtime
Patient inserts and removes
Local or systemic
What two types of vagina rings are there?
Matrix type- drug dispersed through entire ring volume
Reservoir type- drug dispersed through central core. More complex.
What is an example of a vaginal ring?
NuvaRing- combined contraceptive inserted for 21 days continuous
What are vaginal gels?
Water-based semi solids
Made of water and a gelling agent (carbomer)
Preservative and active drug
Plastic applicator
What is an example of a vaginal gel?
Metrogel- metronidazole for bacterial vaginosis
What are vagina polymer films?
Thin water soluble and polymeric
Dissolve rapidly in vaginal cavity with minimal fluid
Rapid drug release- spermicide
What is a vaginal pessary?
It melts at the body temperature in vaginal cavity
What are examples of vaginal pessaries?
Canestan for thrush
Cervidil- to induce labour at 42 weeks
