Vaginal Delivery

Question 1

What part of the vagina is innervated?

Answer 1

outer 1/4

Question 2

How long is the vagina?

Answer 2

6 - 8.5 cm

Question 3

What angle is the vagina relative to the body surface?

Answer 3

130 degrees

Question 4

What are the layers of the stratified squamous epithelium of the vagina?

Answer 4

1) basal
2) parabasal
3) transitional
4) intermediate
5) superficial

SITPB

Question 5

Which layers of the vaginal epithelium are removed during menses?

Answer 5

superficial & intermediate

Question 6

What are the tissue layers of the vagina?

Answer 6

1) stratified squamous epithelium
2) lamina propria
3) muscular
4) adventitia

Question 7

How thick is the stratified squamous epithelium?

Answer 7

200 - 300 um with rugae

Question 8

What is the turnover of the basal layer?

Answer 8

33 days

Question 9

Describe the cells of the basal layer.

Answer 9

• non-cornified columanr germ cells

- microvilli

Question 10

What layer contains desquamation enzymes for menses?

Answer 10

intermediate

Question 11

What layer metabolizes drugs?

Answer 11

superficial (small amount of metabolism, though)

Question 12

Describe the parabasal layer.

Answer 12

– secretion channels, but no goblet cells

Question 13

Describe the intermediate layer.

Answer 13

• • cells flatten
• • desmosomes present to store enzymes
• • enzymes for desquamation

Question 14

Where do vaginal mucosal secretions originate?

Answer 14

1) ultrafiltration (transudation)
2) basal cell layers
3) cervix

Question 15

What is the function of mucosal secretions?

Answer 15

1) lubrication
2) housekeeping
- - IgA’s
- - microbial metabolism –> acidic pH

Question 16

Describe the components of mucosal secretions.

Answer 16

1) mucus
2) exfoliated cells
3) gland secretions
4) IgA
5) small amount of buffer

Question 17

What is the pH of the vaginal cavity?

Answer 17

3.8 - 4.5 (increases after menopause)

Question 18

What is the pH of semen?

Answer 18

7 - 8

Question 19

What is the major microbe in the vagina?

Answer 19

lactobacillus

Question 20

What is the function of lactobacillus in the vagina?

Answer 20

1) glycogen –> lactic acid

2) bactericidal H2O2 release

Question 21

What enzymes are present in the mucus?

Answer 21

proteases & peptidases

Question 22

How does permeability vary along the vaginal cavity?

Answer 22

orifice end has larger permeability coefficient

Question 23

What is the effect of menses on absorption?

Answer 23

1) changed diffusion path
2) 40% increase in permeability for hydrophilic molecules
3) 3-fold increase for lipophilic molecules

Question 24

What is the mucus diffusion time for negative particles?

Answer 24

1.7 h

Question 25

What is the mucus diffusion time for positive particles?

Answer 25

7 hours

Question 26

How does mucus affect absorption?

Answer 26

significant barrier...negative charge

Question 27

How long does Paragard last?

Answer 27

10 years

Question 28

How long does Mirena last?

Answer 28

5 years

Question 29

What are the safety features in an IUD?

Answer 29

1) string | 2) barium for x-ray

Question 30

What are the disadvantages of IUDs?

Answer 30

1) bleeding 2) cramping 3) insertion by trained provider

Question 31

What are the 3 types of vaginal rings, referring to drug delivery?

Answer 31

1) simple 2) sandwich 3) reservoir

Question 32

Describe the simple vaginal ring.

Answer 32

homogenous drug dispersion in a polymeric ring

Question 33

Describe the sandwich vaginal ring.

Answer 33

Drug is sandwiched between non-medicated core & the outer band

Question 34

Describe the reservoir vaginal ring.

Answer 34

Drug dispersed in central core, encapsulated by polymer

Question 35

What are the coatings for vaginal rings?

Answer 35

1) poly(dimethylsiloxane) 2) silicone also ethylene vinyl acetate butadiene block copolymer in recent testing

Question 36

What are the advantages of vaginal rings?

Answer 36

1) good stability 2) good compliance 3) less likely to cause scarring

Question 37

How is the release rate modified in a vaginal ring?

Answer 37

1) drug core diameter | 2) non-medicated coating thickness

Question 38

What is the only available vaginal film?

Answer 38

OTC spermicidal contraceptive (ineffective)

Question 39

Describe the release of a hydrogel for vaginal delivery?

Answer 39

1) dessicated polymer with trapped drug | 2) hydration --> swelling --> drug escape

Question 40

What is the polymer used in hydrogels?

Answer 40

PEO-urethane

Question 41

Describe the 2 structures for pessaries?

Answer 41

1) drug-impregnated polyurethane sponge | 2) polyurethane sponge covered by drug-polymer

Question 42

What are the 2 types of polyurethane sponges covered in drug/polymer?

Answer 42

Type 1: no RCM (poorly permeable drug) | Type 2: with RCM (permeable drug)

Question 43

What is the intended duration for Type 1 pessaries?

Answer 43

short-term

Question 44

What is the intended duration for Type 2 pessaries?

Answer 44

long-term

Question 45

What are common gelling agents?

Answer 45

1) hydrogels 2) polymers - - starch - - hydroxyethylcellulose - - methylcellulose

Question 46

What is a gel?

Answer 46

semi-solid polymeric matrix comprising small amounts of solid dispersed in relatively large amount of liquid

Question 47

What are the advantages of a vaginal gel?

Answer 47

1) bioadhesive 2) acceptable 3) feasible 4) cheap

Question 48

What are the disadvantages of a vaginal gel?

Answer 48

1) messy, leaky | 2) uncomfortable

Question 49

What are common bioadhesive agents?

Answer 49

1) carbomers 2) carbopols 3) chitosans 4) polycarbophils

Question 50

When are bioadhesives used for vaginal delivery?

Answer 50

1) barrier protection 2) Controlled Release 3) vaccines

Question 51

How do bioadhesives bio-adhere?

Answer 51

via cross-linking with mucous membrane