Pre-pregnancy migraine diagnosis, medication use, and spontaneous abortion: a prospective cohort study

Table 2 Association between migraine and spontaneous abortion (n = 7890)

	SABs	Pregnancies	Crude HR	Adjusted HR^a
Preconception Migraines
No	1199	6207	Ref	Ref
Yes	338	1683	1.05 (0.93–1.18)	1.03 (0.91–1.16)
Earlier losses (< 8 weeks)
No	808	5684	Ref	Ref
Yes	228	1544	1.04 (0.90–1.20)	1.01 (0.87–1.18)
Later losses (≥8 weeks)
No	391	4856	Ref	Ref
Yes	110	1300	1.06 (0.86–1.32)	1.06 (0.85–1.32)
Migraine frequency^b
0	141	693	1.05 (0.88–1.25)	1.03 (0.86–1.23)
1	84	463	0.94 (0.75–1.17)	0.93 (0.74–1.16)
2	48	222	1.13 (0.85–1.51)	1.10 (0.82–1.37)
> 2	55	255	1.14 (0.87–1.50)	1.14 (0.86–1.49)

^aAdjusted for baseline age, partner age, education, BMI, smoking, alcohol use, polycystic ovarian syndrome, endometriosis, anxiety, depression, MDI score, physical activity, stress, caffeine before intake. ^bAssessed during the 4 weeks prior to baseline only