Contraception for a smoker over 35 with migraine with aura and previous venous thrombosis
Sahar is 39, gravida 3 para 3, and attends requesting 'the pill'. She smokes 12 cigarettes daily. She has had migraine with aura since the age of 20, with two attacks in the past year. BMI 33, blood pressure 134/86 mmHg. Twelve years ago she had a proximal deep vein thrombosis on day 10 after her first caesarean; it was treated with six months of warfarin, she has had no recurrence, and no thrombophilia was identified at the time. She works night shifts and is unwilling to consider an intrauterine device because 'a friend had one removed because of pain'. Her cycles are regular. She asks about 'the pill with fewer hormones' and whether she can use emergency contraception if needed.
1. Classify the available methods for this woman and explain the reasoning behind each classification.
Read the worked answer
Combined hormonal contraception is absolutely contraindicated (UKMEC 4) - on three separate grounds, any one of which is sufficient:
- Migraine with aura - the combination of oestrogen and aura raises ischaemic stroke risk; this is category 4 regardless of dose.
- Previous venous thromboembolism - recurrence risk on combined pills is several-fold higher; category 4.
- Smoking at age 35 or over - 12/day puts her in category 3 on that count alone (category 4 if 15 or more per day).
'Lower-dose' pills do not remove these risks; stroke risk with migraine with aura persists even at 20 micrograms of ethinylestradiol.
Progestogen-only methods (category 2 with a past, non-current VTE, no anticoagulation):
- Etonogestrel implant - highly effective, no oestrogen, no daily adherence; the best fit here.
- Desogestrel-only pill - safe; effective with perfect use but typical-use failure is higher in a shift worker.
- DMPA - category 2, but weight gain, delayed return of fertility and bone density considerations make it second line.
- Levonorgestrel intrauterine system - category 1–2, and treats heavy bleeding if it develops.
- Copper IUD - category 1, hormone-free, and doubles as the most effective emergency contraception.
Offer the implant and both IUDs first; supply condoms meanwhile; her blood pressure should be rechecked and managed independently.
2. She insists on a combined pill because her sister takes one. How do you counsel and document this, and what do you do if she refuses every option you offer?
Read the worked answer
Counselling should use absolute numbers rather than reassurance.
Explain that her risk is not a laboratory abstraction: oestrogen plus migraine with aura roughly doubles ischaemic stroke risk, and her previous thrombosis means a recurrence risk on combined pills far above the baseline of about 5 per 100,000 woman-years in non-users. Emphasise that her age, smoking and BMI compound this, and that switching to a 'low-dose' pill does not remove the aura-related risk. Use the UKMEC categories openly - patients accept a category 4 recommendation better when they see that it is a rule applied to everyone, not a personal judgement.
Then make the alternative concrete: the implant requires no daily action, is more effective than the pill, and is not affected by her night shifts. Offer insertion at the same visit if possible, and offer a short course of condoms as a bridge. Correct the misconception about the IUD - pain at insertion is usually brief, and a levonorgestrel system would also help her periods.
If she refuses everything: she has capacity, so respect the refusal, but document the discussion in detail - the risks quoted, the options offered and declined, that she understood and that she can return at any time. Offer condoms, emergency contraception advice, and a follow-up appointment. Do not prescribe a combined pill as a compromise; a documented informed refusal of safe alternatives is defensible, a prescription you know to be contraindicated is not. If she declines all contraception, discuss the possibility of pregnancy, folic acid if she might conceive, and review her blood pressure and smoking.
3. Eighteen months later she returns after unprotected intercourse two days ago. She has a BMI of 33. What are her emergency contraception options, and what follow-up is needed?
Read the worked answer
She needs emergency contraception today; the copper IUD is the best option.
- Copper IUD: the most effective method at any BMI, can be inserted up to 5 days after unprotected intercourse (or up to 5 days after the earliest estimated ovulation), and then provides ongoing contraception for years. Check for contraindications - current pelvic infection, unexplained bleeding, sepsis - none of which she has. Give chlamydia and gonorrhoea screening at insertion if she is at risk.
- Ulipristal acetate 30 mg orally: more effective than levonorgestrel, but efficacy falls with increasing BMI, and if she then starts a hormonal method she must wait 5 days. It is not a contraindication with her thrombotic history, as it is not oestrogen-based.
- Levonorgestrel 1.5 mg: least effective of the three, particularly above a BMI of 26–30; some guidelines use a doubled dose (3 mg) in obesity, though the evidence for that is limited. Do not offer it first here.
Follow-up:
- Pregnancy test if menses are delayed beyond 3 weeks, and warn that unscheduled bleeding can occur.
- The episode is an opportunity to secure a long-acting method: if the copper IUD was inserted, contraception is already covered; if not, arrange the implant or a levonorgestrel system and discuss bridging.
- Recheck blood pressure, revisit smoking cessation, and reinforce that a combined pill remains contraindicated even as a short-term measure.