Lecture 13- Contraception Flashcards
Definition:
any method to prevent pregnancy
Various methods of contraception (3)
- Blocking sperm transport to avoid fertilisation of oocyte
- Disruption of HPG axis- interfere with ovulation
- Inhibit implantation of conceptus into endometrium
Categories of contraception
- Natural
- Barrier
- Hormone control
- short or long acting reversible
- Prevention of implantation- IUD/IUS
- Sterilisation
- Emergency contraception
Barrier method
- Provides physical +/- chemical barrier to stop sperm entering cervix
- Male/female condoms
- Diaphragms/cervical caps
- Spermicides
- Barrier method Advantages
- Reliable
- STI protection
- Barrier method Disad
*
- Disrupts intercourse
- Risk of dislodging
- Allergy/ sensitivity to latex
Natural methods
- abstincence
- withdrawal
- fertility awaness methods
- lactational amenorrhoea method
abstinence advantages vs disad
- Advantage- 100% effective
- Disad
- Not option for most
- Unprepared if sexually active
coitus interruptus means
withdrawal method
- Withdrawal- coitus interruptus advantages vs disadvantages
- Advantages
- No device or hormones
- Disad
- Unreliable
- Pre-ejaculate
- No STI protection
how does Fertility awareness methods work
*
- Monitoring and recording fertility indicators throughout menstrual cycle:
- Cervical secretions and changes in cervix
- Body temp
- Length of menstrual cycle- calendar method
Fertility awareness methods advantages and disadvantages
- Advantages
- No hormones/contraindications
- Disad
- Time consuming
- Unreliable
- No STI protection
- Not suitable for all
-
Lactational amenorrhoea method
- Breastfeeding after childbirth to avoid pregnancy
- Delays return of ovulation
- Can be used effectively for 6 month postnatally
- Exclusive breastfeeding
- Complete amenorrhea
Lactational amenorrhoea method advantages and disadvantages
- Advantages
- No hormones/contraindications
- Disad
- Unreliable after 6 months
- No STI protection
- Not suitable for all
Hormonal control works by
*
- Interrupts HPG axis, prevents Ovulation, may effect endometrial lining
- Short or long acting reversible contraception (LARC)
types of hormonal control
- Combined oestrogen and progesterone- COCP, patch, ring
- Progesterone only pill (POP)
- LARC- progesterone depot and implant
role of progesterone
at high levels
- enhances negative feedback of oestrogen hence
- pre-ovulation- reduces FSH and LH
- inhibtis positive feedback fo high oestrogen –> no LH surge –p> No ovulation
at low levels
- does not inhibit LH surge–> can still obvulate
- will thicken cervical mucus
COCP
- Pill containing
- Synthetic oestrogen and progesterone
how is the COCP (combine oestrogen and progesterone) taken
- Usually taken 21 days with a 7 day break or 21 days + 7 placebo pills
main action of COCP
- prevent ovulation – negative feedback of oestrogen and progesterone on LH surge
- Secondary action- reduce endometrial receptivity to implantation
- Thickens cervical mucus
advantages of COCP
- Advantages
- Reliable if used correctly 99%
- Relieve menstrual disorders
- Decrease risk of ovarian and endometrial cancer
- Decrease acne severity in some
COCP disadvantages
- Disad
- User dependent
- No STI protection
- Medication interaction
- Contraindications
- Raised BMI
- Migraine and aura
- Breast cancer
- Side effects
- Menstrual irregularities
- Breast tenderness
- Mood disturbances
- Increased risk of CV disease, stroke, VTE, breast cancer and cervical cancer
POP
progesterone only pill
what is POP
low dose progesterone
main action of POP
thickens cervical mucous–> preventing entry of sperm
other action:
- Reduced cilia activity in fallopian tubes
- Ovulation not prevented
How is POP taken
daily no break
advantages of POP
- Advantages
- Reliable if used properly 99%
- Can be used if COCP contraindicated
- Disad of POP
- No STI protection
- Strict timing- user dependent
- Menstrual irregularities
- Risk of ectopic pregnancy
Progesterone injection
High dose progesterone- LARC e.g. depo-provera
main action of progesterone injection
- Inhibit ovulation, thicken cervical mucus, thin endometrial lining
how is the progesterone injection delivered
- Given intramuscularly every 12 weeks
- Advantages of progesterone injection
- Reliable
- No known medication interactions
- Can be used if oestrogen contraindicated and raised BMI
- Disadvantages of progesterone injection
- No STI protection
- Not rapidly reversible
- Menstrual irregularities
- Hard to get appointment
Progesterone implant
- Small subcutaneous tube inserted in the arm
- High dose progesterone – LARC
- Main action of progesterone implant
Inhibit ovulation, thicken cervical mucus, thins endometrial lining
- Advantages of progesterone implant
- Reliable
- 3 years lasting
- Can be used if oestrogen contraindicated and raised BMI
- Fertility returns faster than injection
- Disad of progesterone implant
- No STI protection
- Menstrual irregularities
- Complications with insertion and removal
coil works by
inhibiting implantation
types of coil
Intrauterine system (IUS)
Intrauterine device (IUD)
Intrauterine system (IUS)
progesterone releasing coil- local
e.g. mirena
Intrauterine system (IUS) main action
prevent implantation and reduces endometrial proliferation, thickens cervical mucus
ovulation usually continues
intrauterine device- IUD
copper containing coil
intrauterine device main and secondary actions
main action- copper is toxic to ovum and sperm preventing fertilisation
secondary action- cervical mucus changes, endometrial inflammatory reactions inhibits implantation
Advantages of the coil
- Convenient
- 99% effective
- LARC- 3-10 years
- IUS for treatment of menorrhagia
Disadvantages of the coil
- No STI protection
- Complications with insertion-perforation
- Menstrual irregularities
- Displacement/expulsion may occur
sterilisation men
vasectomy
- Vasectomy
- Vas deferens snipped or tied to prevent sperm entering ejaculate
- Under local anaesthetic
- Must do post-vasectomy semen analysis -12 weeks post
- Failure rate 1 in 2000 men
sterilisation female
tubal ligation
Tubal ligation
- Fallopian tube occluded to prevent ovum transport
- Under local/ GA
- Failure rate 1 in 200- 500 depending on method
advantages and disadvantages of sterilisation methods (vasectomy and tubul ligation)
- Advantages- permanent
- Disad
- No STI protection
- Regret
- Not easily reversed
- No available under NHS
emergency contraception used when
following unprotected sexual intercourse (UPSI) or contraceptive failure
types of emergency contraception
levonorgestrel
ulipristal acetate
copper iud
Levonorgestrel
morning after pill- high dose progestogen (artificial progesterone) - inhibits ovulation
ulipristal acetate
selective progesterone receptor modulator- inhibits/delays ovulation
choice of emergency contraception depends on
several factors
- time
always think STI and safeguarding
if UPSI within 72hours
levonorgestrel
- maximum effect if taken within the first 12 hours
- double dose in obese
if UPSI +72h up to 120 hours
ulipristal (effectiveness may be reduced if patient has been taking progestogen) or copper IUD (most effective emergency contraception- can be left in situ for up to 10 years)
contraceptive methods that dont depend on you remebering to take or use them
- contraceptive implant
- intrauterine device (IUD)
- Intrauterine system (IUS)
- contraceptive injection
- sterilisation
contraceptive methods that you have to think about regulalry or use each time you have sex
- condom
- diaphragm/ cap with spermicide
- external condom
- POP
- COC
Contraceptive patch - contraceptive vaginal ring
- fertility awareness method
summary of contraceptive methods- look in notes and read through pls and thanks :))))
