Fertility Control Flashcards
What are the different methods of contraception?
- Natural → no intercourse near time of ovulation, acceptable to catholic church, no drugs requested
- Barrier → low health risk, needs high motivation, some protection against STIs
- Hormonal → highly effective but complex health risks (can be: progesterone-only or combined)
- IUCD → convenient + effective if not contraindicated
- Sterilisation → very effective but irreversible
When is a woman’s (most) fertile period, during their cycle?
- 6 days before ovulation (day 14) → life of sperm
- 2 days after ovulation → life of ova
Barrier methods of contraception reduce the risk of pregnancy by acting as a barrier to stop the sperm and ovum meeting and so preventing fertilisation. These should be recommended to patients for all types of sexual contact to reduce sexually transmitted infection (STI) transmission.
What are the benefits and limitations of male condoms?
- Benefits → only used during intercourse; reduces STI transmission; rarely side-effects from use
- Limitations → can break, split or tear during use; can interrupt intercourse to put male condom on; need to know correct technique for using condoms; some patients are allergic to latex condoms
98% effective with perfect use but typical use is 82% effective
Female condoms are a barrier made of polyurethane that goes inside the vagina to prevent sperm from passing through the cervix and fertilising an ovum.
What are the benefits, limitations and effectiveness of female condoms?
- Benefits → only used during intercourse; reduces STI transmission; rarely side-effects from use
- Limitations → can break split or tear during use; may interrupt intercourse to put on; need to know correct technique; female condoms not as widely available
With perfect use, 95% effective. Otherwise, typical use is 79%.
The diaphragm (or contraceptive cap) is a silicone cup which is placed over the cervix as a barrier to sperm.
What are the benefits and limitations of the diaphragm?
There are two types: cervical caps, which fit over cervix and the diaphragm which is held in place between pubis and sacral curve
- Benefits → only used during intercourse; can be put in place in advance of intercourse; rarely side-effects from use
- Limitations → can break, split or tear during use; may interrupt intercourse to put diaphragm in; pts need to know correct technique; does not protect against STIs
92-96% effectiveness with perfect use but 71-88% effectiveness typically.
How do combined contraceptives work?
- contain forms of both oestrogen and progresterone
- work by mimicking luteal phase of menstrual cycle
- leading to inhibiton of HPG axis
- prevents release of LH and FSH needed for ovulation
- combined contraceptives also thicken cervical mucus → prevents sperm passage
- thin the endometrium too → reduce chance of implantation
What are examples of combined contraceptives?
- Combined oral contraceptive pills (COCP)
- Contraceptive patches
- Vaginal rings
Before discussing and offering contraception, it is important to exclude pregnancy.
What features of the history from the patient suggest that professionals can be ‘reasonably certain’ that a woman is not currently pregnant?
- has not had intercourse since last normal menses
- has been correctly + consistently using reliable method of contraception
- is within the first 7 days of onset of a normal menstrual period
- is within 4 weeks postpartum for non-lactating women
- is within first 7 days post-abortion or miscarriage
- is fully or nearly fully breastfeeding, amenorrhoeic and less than 6 months postpartum
A pregnancy test, if available, adds weight to the exclusion of pregnancy but only if ≥3 weeks since the last episode of UPSI. Health professionals should also consider if a woman is at risk of becoming pregnant as a result of UPSI within the last 7 days and undertake pregnancy test where appropriate.
What are contraindications of combined contraception?
- migraine with aura
- current breast cancer
- atrial fibrilation
- SLE positive for antiphospholipid antibodies
- age >35 + smoker >15 cigs/day
- hx of stroke
- hx of VTE
- major surgery w/ prolonged immobilisation
- known thrombogenic mutations
- complicated valvular or congenital heart disease
- hypertension: >160 systolic or >100 diastolic
- hx of ischaemic heart disease
- severe liver disease
- complicated diabetes
Some evidence to suggest breast cancer risk is increased in those using combined contraceptives. However, risk reduces to normal levels 10 years after stopping contraceptive. Seek oncology advice where appropriate.
What are key features of the combined oral contraceptive pill?
- contain oestrogen + progesterone
- pts take 1 pill at the same time each day for 21 days
- they then have a 7 day break with either no pills or placebo pills
- here they have period-like withdrawal bleed
- start next pack of pills after this
- most suited to women who are good at remembering to take pills daily
- and those who tolerate hormonal contraceptives
- 99% effective with perfect use
- if COC started in first 5 days of cycle then no need for additional contracepton, if any other point then condoms should be used for first 7 days
- tailored regimes coming into place → no med benefit from having withdrawal bleed eg. no pill-free interval or ‘tricycling’ (take three 21-day packs back-to-back before having 4 or 7 day break)
What are the benefits of the COCP?
- 99% effective
- does not interrupt intercourse
- can be stopped at short notice if not tolerated
- may make periods more regular, lighter + less painful
- may reduce risk of ovarian, endometrial and bowel cancer
- may have therapeutic benefits in gynaecological disorders such as endometriosis and menorrhagia
What are the limitations and side-effects of the COCP?
- typical use = 91% effectiveness
- effectiveness reduced if pill is forgotten
- side-effects → headaches, nausea, breast tenderness + mood swings
- vomiting + diarrhoea may affect effectiveness - if vomit within 3hrs, take next pill in pack
- certain drugs including some antibiotics and anti-epileptic drugs may affect effectiveness
- increases risk of VTE + stroke
- potentially increases risk of breast cancer while using COCP
- does not protect from STIs
What drugs interfere/interact with the COCP, so therefore should be avoided?
- anticonvulsants → phenobarbitone, phenytoin, carbamazepine, topiramate
- anti-tuberculosis → rifampicin
- antifungal → griseofulvin
- protease inhibitors → ritonavir, nelfinavir
- misc → lansoprazole, tacrolimus, modafinil
- other antibiotics → penicillins, ampicillin, tetracyclines, cephalosporins
- St John’s wort
What is the rule in taking the COCP when a patient is undergoing surgery?
- any operation where pt will be in bed for 2+ days post-op increases the risk of developing a DVT, this also applies to any op which takes over 30 mins
- combined pills should be stopped 4 weeks before procedure + not started until the next period at least two weeks after surgery
- operations on legs include arthroscopies and injection of varicose viens, and female laparoscopic sterilisation have a low risk for VTE + COC can be continued
- where surgery is performed as an emergency, the COC should be stopped and surgeon may give heparin
- should also be stopped when legs are in plaster or there is immobility not associated w/ surgery + heparin may be given
How to stop the COCP when planning a pregnancy?
- complete to end of pack
- aim to have at least one natural period prior to conception
- this facilitates calculating date of delivery
- start folic acid as soon as COC stopped
COCP: What happens if there is no bleeding in the pill free interval?
- as long as woman is not pregnant
- women can be reassured that there is nothing to worry about
- can continue the COC in usual way or try lower dose pills
What happens if there is breakthrough bleeding whilst taking COC?
- check taking correctly
- is there a drug interaction?
- women need to be examined to exclude cervical polyps/carcinoma
- screen for sexually transmitted infection
May need to change to a different COC
Do women need a break from the COCP from time to time?
- no - there is no benefit to this
What are the rules if the COCP pill is missed?
- one missed pill → take last pill you missed now even if it means taking 2 pills in one day, continue taking the rest of pack as usual, emergency contraception not required but may be considered if pills have been missed earlier in the pack or in the last week of previous pack
- two or more missed pills → take last pill you missed now, continue taking rest of pack as usual and leave any earlier missed pills; use an additional method of contraception for next 7 days (condoms); if UPSI in previous 7 days, seek advice
- The need for emergency contraception depends where you are in the pack:
- week 1 → EC may be needed
- week 2 → EC not needed
- week 3 → EC not needed but miss hormone free interval (HFI) and carry straight on to next pack
Emergency contraception is used by women who have had unprotected intercourse but do not want to become pregnant. There are three methods of emergency contraception. Levonelle® and ellaOne® are forms of emergency contraceptive pills or morning-after pills. The copper coil can also be used as emergency contraception. All are more effective the earlier they are used following unprotected intercourse.
