Migraine and OCs: What options are open?

How many women do you see in your practice who say they have chronic or recurrent headaches? If the numbers are high, don’t be surprised: Headaches are a frequent occurrence in women of reproductive age.1 But what is your approach in determining whether these women may use combined oral contraceptives (OCs)?

A just-published meta-analysis of several studies highlights the risk of stroke in women who use oral contraceptives and who have migraine headaches.2 What role does migraine headache play in determining OC use?

Clinicians must use their diagnostic skills in determining what type of headache women are describing when offering guidance on birth control, says John Guillebaud, MD, emeritus professor of family planning and reproductive health at University College in London. While guidelines from the Geneva-based World Health Organization (WHO) state that nonmigrainous headache, whether mild or severe, is not a contraindication to OC use,3 the agency’s Medical Eligibility Criteria lists migraine headaches with aura at any age as a clear contraindication to combined oral contraceptive use.4

Why is a differential diagnosis so important? Migraine headaches, particularly those where before the headache itself there is aura, are an independent risk factor for stroke among reproductive-age women, says Guillebaud. In 99% of cases, aura involved some loss of part of the visual field, often described as surrounded by flashing lights or bright zigzag lines.

Migraine headaches represent more than half of all chronic, recurring headaches in the United States, and most of those with migraines are women.5 Migraine symptoms may include:

  • intense throbbing, pulsing, or dull aching pain on one or both sides of the head (six out of 10 migraine sufferers have pain on only one side of the head, while four out of 10 have pain on both sides);
  • nausea with or without vomiting;
  • changes in vision, including blind spots or blurry vision;
  • pain that worsens with physical activity;
  • pain that gets in the way of daily activities;
  • sensitivity to light, sound, or odors;
  • feeling cold or sweaty;
  • tender or stiff neck;
  • lightheadedness;
  • scalp tenderness.6

If it is determined that headaches are migrainous in nature, clinicians then need to assess whether focal neurological symptoms within an aura are associated with the attacks.

Aura typically starts before the headache as a flickering, uncolored zigzag line in the center of the visual field and gradually progresses laterally to the periphery of one hemifield, usually leaving a scotoma, which is bright, not an area of blackness.7 If sensory or motor symptoms occur, they usually are unilateral and rarely without associated visual symptoms.7 These symptoms typically last less than one hour, resolving before the onset of headache.8 Clinicians can identify aura by asking, "Have you ever had visual disturbances lasting five to 60 minutes followed by headache?"9 (Use visual cues to determine aura; see the diagnostic tip)

Why is it so important that a determination of aura be reached? A large case-control study performed in Europe found that women with migraines with aura had a fourfold increased risk of ischemic stroke.10 Other studies have estimated relative risks as high as 6.211 or even 14.8.12

There remains some controversy in the literature regarding the potential link (positive association) between migraine and stroke; several studies have had conflicting results, says Mahyar Etminan, a postdoctoral fellow in clinical epidemiology at Royal Victoria Hospital in Montreal, who served as lead author of the just-published meta-analysis. The risk of migraine among users of oral contraceptives must be further investigated, authors of the meta-analysis conclude.2

"Those who have migraines, take [the] Pill, smoke, or may have other stroke risk factors may want to be more cautious and learn the signs and symptoms of migraine," states Etminan.

For women with no other risk factors for stroke (diabetes mellitus, hyperlipidemia, hypertension, obesity, family history of arterial disease below 45 years, and smoking cigarettes) who have nonmigrainous headaches, mild or severe, the WHO criteria place the least restrictions on combined OC use. WHO ranks initiation of combined OCs at 1 — a condition for which there is no restriction for the use of the contraceptive method.4 The contraceptive transdermal patch and the contraceptive vaginal ring fall in this same category.

However, for women with migraine headaches without aura, age plays a determining factor, according to the WHO guidelines. For those younger than age 35 and without other risk factors, the benefits of initiating OC use outweigh the potential risks (WHO Category 2); however, for those 35 and older, the risks outweigh the benefits. Initiation of OCs in these older women is ranked at 3 (a condition where the theoretical or proven risks usually outweigh the advantages of using the method), while continuation is ranked at 4 (a condition which represents an unacceptable health risk if the contraceptive method is used).4

What methods may these women use? Look at any nonestrogen-containing methods such as depot medroxyprogesterone acetate (DMPA) and progestin-only pills as well as intrauterine contraception, says Guillebaud.

References

1. American College of Obstetricians and Gynecologists. The use of hormonal contraception in women with coexisting medical conditions. ACOG Pract Bull 2000; 18:4-5.

2. Etminan M, Takkouche B, Isorna FC, et al. Risk of ischaemic stroke in people with migraine: Systematic review and meta-analysis of observational studies. BMJ 2005; 330:63.

3. Combined oral contraceptives and migraine. Contraception Report 2003; 14:4-8.

4. World Health Organization. Medical Eligibility Criteria for Contraceptive Use, 3rd ed. Geneva; 2003.

5. National Headache Foundation. Migraine facts. Chicago; 2001. Accessed at www.headaches.org/professional/presskit/NHAW02/NHAW02migrainefacts.html.

6. Andreola NM. What you should know about migraine. Fem Patient 2004; November. Accessed at www.femalepatient.com/pdf/patob_1104.pdf.

7. Russell MJ, Olesen J. A nosographic analysis of the migraine aura in a general population. Brain 1996; 119:355-361.

8. MacGregor EA, Guillebaud J. Migraine and stroke in young women. Authors’ results suggest that all types of migraine are contraindications to oral contraceptives. BMJ 1999; 29; 318:1,485; author reply 1,486.

9. Gervil M, Ulrich V, Olesen J, et al. Screening for migraine in the general population: Validation of a simple questionnaire. Cephalalgria 1998; 18:342-348.

10. Chang CL, Donaghy M, Poulter N. Migraine and stroke in young women: Case control study. The World Health Organisation Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception. BMJ 1999; 318:13-18.

11. Tzourio C, Tehindrazanarivelo A, Iglésias S, et al. Case-control study of migraine and risk of ischaemic stroke in young women. BMJ 1995; 310:830-833.

12. Marini C, Carolei A, Roberts RS, et al. The National Research Council Study Group. Focal cerebral ischaemia in young adults: a collaborative case-control study. Neuroepidemiology 1993; 12:70-71.