Menstrual Cycle & Contraception Flashcards
Outline the name of the stages in the menstrual cycle
- Menstruation
- Proliferation phase
- Luteal/ secretory phase
Outline the 1st stage of the menstrual cycle
Day 1-4 - menstruation
- Endometrium is shed as its hormonal support is withdrawn
- Myometrial contraction can be painful
Outline the 2nd stage of the menstrual cycle
Day 5-13 - proliferative phase
- Gonadotrophin-releasing hormone (GnRH) pulses released from Hypothalamus
- GnRH stimulates FSH & LH release from Ant. Pituitary
- FSH & LH induce Follicular growth
- Follicles produce Oestradiol & Inhibin
- Inhibit FSH
- Stim. LH
- Leads to LH surge stim. ovulation 36hrs later
- Oestradiol stim. stromal cell proliferation & gland elongation (a ‘proliferative endometrium’)
Outline the 3rd stage of the menstrual cycle
Day 14-28 - luteal/ secretory phase
- Follicle from which egg released become Corpus Leuteum (CL)
- Releasing Oestradiol & Progesterone
- More P released relatively
- Releasing Oestradiol & Progesterone
- P peaks 7 days later (~21) inducing Secretory changes in endometrium
- Stromal cells enlarge
- Glands swell
- Blood supply increases
- No fertilisation
- CL fails and O&P withdrawn
- Cycle restarts
- Fertilisation
How is the efficacy of contraception measured?
- Using the Pearl Index (PI)
- PI of 2 = out of 100 women using it for 1 year, 2 will be pregnent
- Efficacy is variable in user-dependant contraceptives (ie the pill, condoms)
- Higher with perfect use
- Lower with typical use
Outline the categories of hormonal contraception
- Progestogen only pill (mini-pill)
- Progestogen as depot
- Nexplanon
- Depo-Provera & Noristerat
- Levonorgestrel-containing intrauterine system (IUS)
- Combined hormonal contraception (CHC) (progestogen & oestrogen)
- Combined oral contraception (the pill, COC, mono/bi/tri phasic)
- Transdermal patch
- Vaginal ring
COC pill: mechanism of action
Contains oestrogen & progestogen
- -ve feedback on gonadotrophin release, inhibiting ovulation
- thins endometrium
- thicken cervical mucus
What are the types of COC pill?
Outline how they are taken.
All contrain oestrogen & progestogen.
- Ethinyloestradiol +
- 3wks on, 1wk off
- monophasic 20-40ug
- Oestradio Valerate (metabolised to Oestradiol)
- Dienogest (natural progestogen)
- 4 phases over 26d, 2d off
- Lower lipid & haemostatic effects
What is the efficacy of COC pill?
PI = 0.2
lower dose = higher dose
Outline progestogenic side effects?
- Mastalgia
- Weight gain
- Depression/ PMT-like symptoms
Outline oestrogenic side effects?
- Nausea
- Headaches
What are the risk factors of taking COC pill?
Major
- DVT (particularly 3rd gen)
- MI
- CVA
- Migraine
- Hypertension
- Carcinoma
- Breast & Cervical
Risk factors are multiplied by;
- Smoking
- Inc age
- Obesity
What are the relative & absolute contradinations for COC pill?
Relative
- BMI 35-39
Absolute
- 4 wks pre-surgery
- BMI >40
- Age >35
- Smoker >15
- First 6wks breastfeeding
- History of any of the major risk factors
Outline the specific thromboembolic risks for;
- Normal women
- Pregnant
- Old 30ug COC pill
- New 30ug COC pill
- Smoking + COC pill
in 100,000 women
- Normal women - 5
- Pregnancy - 60
- Old 30ug - 15
- New 30ug - 25
- Smoking + COC pill - 60
What affects the absorption of COC pill?
How do you ensure contraception?
- Antibiotics
- Continue taking COC
- Condoms during & 7d after
- Missed pill policy (MPP)
- Take pill asap
- If missed 2+ use condoms for 7 days
- Diarrhoea
- Continue taking
- MPP
- Vomitting
- Within 2hr retake COC
- After 2 hours MPP
What is the combined transdermal patch?
What type of oestrogen is used?
How must it be used?
Combined transdermal patch eg Evra
- Releases ethinyloestradiol (34ug)
- 3wks on (patch/week) & 1wk off
What is the combined vaginal ring?
What type of oestrogen & progestogen does it release?
How should it be used?
Combined vaginal ring eg Novaring
- Ethinyloestradiol (15ug)
- Etonogestrel (120ug) [progestogen]
- 3wks on/ 1wk off
For the progestogen-only pill, outline;
- Name & type of progestogen used
- Mechanism of action
- How its taken
Name: progestogen type
- Micronor: Norethisterone (350ug)
Mechanism
- Makes cervical mucus hostile to sperm
- Inhibits ovulation in 50% women
Taken daily at the same time (+/- 3hr)
What is the efficacy of the progestogen-only pill?
PI = 1
Outline the S/E of the progestogen-only pill?
Progestogenic
- Mastalgia
- Weight gain
- Depression/ PMT-like symptoms
Other;
- Spotting (breakthrough bleeding)
Outline the positives & benefits of the progestogen-only pill (not including S/E)
Positives
- Can be used in all situations where COC pill is contraindicated
Negatives
- Timing is meticulous
For Depo-Provera, outline;
- What it consists of
- How it is administered
- Indications
- Common S/E, risks & contraindications
- Efficacy
- Progestogen: Medroxyprogesterone acetate
- IM every 3/12 (150ug)
- Indications
- Compliance problems
- Lactation
- S/E
- Breast discomfort
- Weight gain
- Depression/ PMT-like symptoms
- Osteoporosis (not young & elderly)
- Irregular bleeding in first weeks
- PI <1
For Nuristerat, outline;
- What it consists of
- How it is administered
- Indications
- Common S/E, risks & contraindications
- Progestogen: Medroxyprogesterone acetate
- IM every 8 weeks
- Indications
- Short term interim contraception
- S/E
- Breast discomfort
- Weight gain
- Depression/ PMT-like symptoms
For Nexplanon, outline;
- What is consists of
- How it is administered
- Efficacy
- S/E
- 40mm rod containing progtogen: Etonogestrel
- Sub-dermal upper arm with local anaesthetic for 3 years
- PI <1
- Progestogenic S/E
- Mastalgia
- Weight gain
- Depression/ PMT-like symptoms
What are the emergency contraceptives available?
- Morning after pill
- Intrauterine device (IUD)
For the morning after pill, outline;
- Types
- Mechanism of action
- Administration
- Efficacy
- Levonelle
- 1.5mg Levonorgestrel (progestogen)
- Mechanism
- Affects sperm function & endometrial receptivity
- May prevent ovulation
- Best <24hr (95%), <72hr (58%)
- Uliprostal (ellaOne)
- Selective progesterone receptor modulatior (SPRM)
- Mechanism
- SPRM prevents/ delays ovulation
- Reduce embryo implantation
- Used <120hr after intercourse
How do IUD’s work as emergency contraception
- Prevent implantation
- Most efficacious method of emergency contraception
- Upto 5 days post sex/ first day of ovulation
- Antibiotics given prophylactically
Outline the different types of barrier contraception
- Male condom
- Female condom
- Diaphragms & caps
- Spermicides
- IUD’s
For diaphragms & caps;
- When should they be inserted
- What is their efficacy
- Pre-intercourse for 6 hours
- PI = 5
How do spermicides work?
- What ingredients are in them?
- Function as a barrier
- Contain nonoxynol-9; spermicide
Outline the types of IUD and how each function
- Copper
- Toxic to sperm
- Block fertilisation & implantation
- Hormonal - progesterone
- Levonorgestrel (Mirena)
- IUS
Outline the complications of IUDs?
- Copper
- Heavy & painful bleeding
- ALL
- Pain/ cervical shock (inc vagal tone)
- Perforation
- Expulsion
- Infection (normally a residual infection)
Outline the types of female sterilization?
- Filshie clips
- Inserted laparoscopically
- Occludes fallopian tube
- Microinserts
- Hysteroscopic placement of microinserts intro proximal part of each tubal lumen
- Essure
Outline how male sterilization works?
- Ligation & removal of a small segment of the vas deferens - preventing release of sperm
- Azoospermia confirmed by 2 semen analyses (may take 6 months to achieve)
Outline how male hormonal contraception may work?
- Spermatogenesis halted by administration of progestogens
- Reduces gonadotrophin drive to testes
- Also halts androgen production so testosterone replacement therapy required
Outline natural contraception methods and how they work?
- Lactation
- High prolactin levels during lactation inhibit GnRH
- Withdrawal method
- ‘Rhythm’ method
