Contraception Flashcards
What is contraception?
Any method to prevent pregnancy
What are the different types of contraception?
Natural Barrier Hormonal control Prevention of implantation Sterilisation Emergency contraception
What are the natural methods of contraception?
Abstinence
Withdrawal method
Fertility awareness
Lactational amenorrhea
What are the advantages of abstinence?
Only 100% reliable method of contraception
What are the disadvantages of abstinence?
No sex
What is the withdrawal method?
Removal of penis before ejactulation
What are the advantages of the withdrawal method?
No devices
No hormones
What are the disadvantages of the withdrawal method?
Unreliable - some sperm in pre-ejaculate
No STI protection
What is fertility awareness?
Use of fertility indicators to identify fertile and infertile points of the menstrual cycle
What are fertility indicators?
Cervical secretions
Basal body temperatures
Length of menstrual cycle
What are the advantages of fertility awareness?
No hormones
No devices
What are the disadvantages of fertility awareness?
Unreliable
No STI protection
What is the lactational amenorrhea method?
Breast feeding delays return of ovulation
- suckling stimulus disrupts release of GnRH
- affects HPG axis
What are the advantages of the lactational amenorrhea method?
No hormones
No devices
What are the disadvantages of the lactational amenorrhea method?
Only effect up to 6 months post partum
Female must be amenorrhoeic
Unreliable
No STI protection
What are the available barrier methods?
Male/female condoms
Diaphragm/caps
What are the advantages of barrier methods?
Reliable
STI protection
Male condom widely available
What are the disadvantages of barrier methods?
Reduce pleasure?
Risk of expiration
Allergy to latex
What types of hormonal contraception are available?
Combined oestrogen + progesterone
Progesterone only
What combined hormonal contraception are available?
COCP
Vaginal ring
Patches
What progesterone only hormonal contraception are available?
High dose
- injection
- impant
Low dose
- POP
How does high dose progesterone act as contraception?
Enhances negative feedback of oestrogen - reduces LH + FSH
Inhibits positive feedback of oestrogen - prevents LH surge = no ovulation
How does low dose progesterone act as contraception?
Thickens cervical mucus - physical barrier to sperm
How does the COCP work?
Prevents ovulation
Reduces endometrial receptivity - inhibits implantation
Thickens cervical mucus
What are the rules for missed COCP pills?
1 day
- continue as normal
- take 2 in one day if necessary
2+ days
- take one missed pill
- continue as normal
- use extra protection for 7 days
What are the advantages of the COCP?
98% effective
Can relieve menstrual symptoms
Reduces risk of ovarian cysts
Reduces risk of ovarian + endometrial cancer
What are the disadvantages of the COCP?
No STI protection Contraindications Side effects Increased risk of breast + cervical cancer VTE risk
What are the contraindications to the COCP?
BMI >35
Migraines
Breast cancer
What are the side effects of the COCP?
Breakthrough bleeding
Breast tenderness
Mood disturbances
What is the action of progesterone injections?
Prevent ovulation
Thicken cervical mucus
Prevent endometrial proliferation
What are the advantages of progesterone injections?
Reliable
Doesn’t interrupt sex
What are the disadvantages of progesterone injections?
12 weekly injections
Side effects
Delay in fertility return ~6months
No STI protection
What is the action of the implant?
Inhibit ovulation
Thicken cervical mucus
Prevent endometrial proliferation
How long does the implant last?
3 years
What are the advantages of the implant?
Reliable
LARC
Natural fertility returns quickly
What are the disadvantages of the implant?
Minor procedure to insert
Side effects
NO STI protection
What is the action of the POP?
Thickens cervical mucus
What are the advantages of the POP?
Quickly reversible
Doesn’t interrupt sex
Can be used if COCP contraindicated
What are the disadvantages of the POP?
User dependant Menstrual problems are common Interacts with other medication Risk of ectopic pregnancy No STI protection
What are the missed POP pill rules?
< 3 hours late
- take missed pill asap
- carry on as normal
> 3 hours late
- take asap
- carry on as normal
- use extra protection for 2 days
What are the different devices for inhibiting implantation?
IUS
IUD
What is the action of the IUS?
Releases progesterone
Prevent implantation
Reduce endometrial proliferation
Thicken cervical mucus
How long does an IUS work?
5 years
What is the action of an IUD?
Copper is toxic to sperm
How long does an IUD work?
10 years
What are the advantages to coils?
Convenient
Long duration of action
What are the disadvantages of coils?
Unpleasant insertion Risk of uterine perforation Menstrual irregularity No STI protection May be expelled from uterus
What are the different types of sterilisation?
Vasectomy
Tubal ligation
What happens in a vasectomy?
Vas deferens cut to prevent sperm entering during ejaculate
What is the failure rate for a vasectomy?
1 in 2000
What happens in tubal ligation?
Fallopian tubes cut to stop ovum entering uterus
What is the failure rate for tubal ligation?
1 in 200/500
What are the types of emergency contraception?
Levonorgestrel
Ulipristal acetate
