contraception Flashcards
what are the reasons for using contraception?
- Preventing pregnancy-related health risks in women
- Reducing infant mortality
- Helps to prevent HIV/AIDS
- Empowering people and enhancing education
- Reducing adolescent pregnancies
- Slowing population growth
what are the sites of action of contraception?
ovary
endometrium
Cervix
what drugs target the ovary?
Combined hormonal contraception, Progesterone-only pill, Injection, Implant
what drugs target the endometrium?
IUS
IUD
what drugs target the cervix?
IUS, Progesterone-only pill, CHC
what hormones are involved in the female menstruation cycle?
FSH
oestrogen
LH
Progesterone
what does FSH do in the female menstrual cycle?
Ovarian follicular development, Oestrogen levels rise
what does oestrogen do in the menstrual cycle?
Endometrial proliferation, LH surge
what does LH do in the menstrual cycle?
Ovulation, Corpus luteum formation, Oestrogen and progesterone rise
what does progesterone do?
endometrial thickening
what is the combined hormonal contraception?
Combination of oestrogen and progesterone
what is the mode of action of CHC?
o Inhibits LH and FSH –> prevents ovulation
o Thickens cervical mucus –> natural sperm barrier
o Thins endometrium –> prevents implantation
what is the failure rate of CHC?
o If used perfectly 0.3 per 100 woman years
o If used typically 9 per 100 woman years
what are the types of CHC?
Birth control pills, Vaginal ring, Birth control patch
what are the advantages of CHC?
o Reduce menorrhagia / dysmenorrhoea / PMS
o Reduce risk of PID
o Reduce risk of benign ovarian tumours / colorectal cancer / ovarian cancer
o Improve acne
o May reduce risk of fibroids, ovarian cysts and non-cancerous breast disease
what are the disadvantages of CHC?
o Higher risk of VTE / stroke / CV disease
o Increased risk of breast cancer (returns to normal 10 years after stopping)
o Small increased risk of cervical cancer
o Depression / low mood
o Temporary side effects include headache, nausea, breast tenderness, mood changes
o Breakthrough bleeding
what are the contraindications of CHC?
o VTE / CV disease (inc atrial fibrillation) / stroke – either personal or close family history
o Hypertension
o Any thrombophilic condition
o Oestrogen-dependent cancers (usually breast or cervical)
o Migraine with aura
o Liver disease
o Combination of risk factors for cardiovascular disease, e.g. hypertension/diabetes
o Over 35 years and a smoker
o BMI > 35
o < 6 weeks postpartum if breastfeeding
o <3 weeks postpartum if non-breastfeeding
what is progesterone only contraception?
various different forms of synthetic progesterone
what is the mode of action of progesterone only contraception?
o Thickens cervical mucus natural sperm barrier
o Thins endometrium prevents implantation
o Inhibits ovulation (97% desogestrel, 60% others)
what is the failure rate of progesterone only contraception?
oIf used perfectly 0.3 per 100 woman years
o If used typically 9 per 100 woman years
what are the types of progesterone only contraception? how long do they last?
o POP
o Injection (Depo-Provera) - lasts 3 months
o Implant (Nexplanon/Implanon) - lasts 3 years
o Intrauterine system (IUS) - lasts 5 years
what are the advantages of progesterone only contraception?
o Reduces menorrhagia / dysmenorrhoea / PMS; Amenorrhoea; Reduce risk of endometrial cancer; Can be used when breastfeeding; Fewer adverse effects compared to CHC
what are the disadvantages of the progesterone only contraception?
o Irregular spotting
o Acne
o Headaches, nausea, mood swings, bloating, breast tenderness, weight gain
o Ovarian cysts
o All above usually settle after 6 months
o IUS only – uterine perforation, expulsion, ectopic pregnancy, PID
what are the contraindications of progesterone only pill?
o Unexplained vaginal bleeding o If VTE / stroke / IHD occur during use o Breast cancer o Severe liver disease o IUS only – PID, >48h - <4w postpartum
what is the mode of action of the intrauterine device?
o Copper is spermicidal
o Thickens cervical mucus natural sperm barrier
o May act as physical barrier to implantation
what is the failure rate of the intrauterine device?
0.6-0.8 per 100 women
what are the advantages of the IUD?
Long-acting (5-10 years), No hormones
what are the disadvantages of the IUD?
Uterine perforation, Expulsion, Ectopic pregnancy, PID, Menorrhagia (IUD only)
what are the contraindications of the IUD?
o Unexplained vaginal bleeding; PID / untreated STI; Cancers (cervical, endometrial); Puerperal sepsis; > 48 hours - <4 weeks post-partum
o Distorted uterine cavity (may be appropriate under imaging guidance after discussion)
what is the success rate of the male condom?
o If used perfectly failure rate 2 per 100 woman years
o if used typically failure rate 18 per 100 woman years
what is the success rate of the diaphragm/cap?
o If used perfectly, failure rate 6 per 100 woman years
o If used typically, failure rate 12 per 100 woman years
what are the advantages of the barrier methods?
only contraception to protect against STIs
what does natural planning involve?
education and charting of various indicators of female fertility including: Temperature, Consistency of cervical mucus, Position of cervix, Day of cycle
what is the failure rate of natural planning?
o If used perfectly failure rate is 0.5 per 100 woman years
o If used typically failure rate is 24 per 100 woman years
what are the advantages of family planning?
o Does not involve using any chemicals or physical devices
o No physical side effects
o Can help person to recognise normal and abnormal vaginal secretions
o Can help with communication around fertility and sexuality
o Acceptable to all faiths and cultures
what are disadvantages of natural planning?
o Takes 3-6 menstrual cycles to learn effectively
o Have to keep daily records
o Some events - e.g. illness, lifestyle, stress, travel – may make fertility indicators harder to interpret
o Need to avoid sex or use barrier methods during fertile time
o Does not protect against STIs
what is the mode of action of the withdrawal method?
Male partner pulls penis out of vagina before he ejaculates so that sperm cannot reach uterus
what is the failure rate of the withdrawal method?
22 per 100 women
what is the mode of action of female sterilisation?
Typically laparoscopic bilateral tubal occlusion with clips/ligation/rings/diathermy
can be done under local or general anaesthetic
what is the failure rate of female sterilisation?
lifetime failure rate 1 in 200
what is the mode of action of male sterilisation?
o Ligation/diathermy/excision of vas deferens bilaterally
o Done under local anaesthetic
what is the failure rate of male sterilisation?
Lifetime failure rate 1 in 2000
what is the female risk of sterilisation?
pain, heavier periods <30 years, ectopic pregnancy, injury to internal organs, regret
what is the risk of male sterilisation?
pain, swelling, infection, retrograde ejaculation, regret
what is the mode of action of oral emergency contraception?
delayed ovulation
name common oral emergency contraceptions?
levonelle
ellaone
what is levonelle?
Levonorgestrel 1.5mg single dose. Licensed up to 72 hours post-UPSI. Pregnancy rate 0.6 – 2.6%
what is ellaone?
Ullipristal acetate 30mg single dose. Licensed up to 120 hours post-UPSI. Pregnancy rate 1 – 2%
what is the mode of action of IUD emergency contraception?
Inhibits fertilisation by direct toxicity
Affects implantation by causing endometrial inflammation
what is the overall pregnancy rate?
Licensed up to 5 days after UPSI / earliest possible ovulation
