Migraines are defined as recurrent headaches separated by symptom-free intervals and often accompanied by nausea and light sensitivity. Migraines are often accompanied by visual symptoms and are relieved by sleep; furthermore there is usually a throbbing quality.
It is generally thought that migraine often (77%) improves during pregnancy, especially in the 2nd (83%) and 3rd trimester (87%) (Sances et al, 2003). Some hold that migraine with aura does not improve. (Torelli et al, 2010).
Serum levels of estradiol and progesterone begin to rise in the mother during the 6th to 8th weeks of pregnancy as the placenta begins to produce steroids and they continue to gradually increase to their highest levels during the third trimester (Martin et al, 2006). During the third trimester, serum estradiol levels are 30-40 times higher and progesterone levels are 20 times higher than peak levels during the native menstrual cycles. There are also many other hormones that are increased during pregnancy. High levels of both estrogen and progesterone are reportedly necessary to produce the relative tolerance to pain called the "analgesia of pregnancy". (Martin et al, 2006).
Most clinicians advise avoidance of migraine prevention medications, using instead dietary modification, ice, or simply rest. Botox injections would also seem to us to be a reasonable modality, as it is difficult to envision an effect of a local agent on the fetus. Acupuncture and some vitamins are also recommended by some, such as oral magnesium, riboflavin, and Co-Q10.(Airola, Allais et al. 2010). See this page for more information about how these are taken.
Medications were previously categorized into risk categories with respect to pregnancy. In 2014, the FDA removed these letter categories with the intent that they be replaced by statements. We don't think that this made matters any better. But perhaps it made lawsuits more difficult.
If medications are deemed necessary, we suggest consulting the most current edition of the highly regarded reference "Drugs in Pregnancy and Lactation by Briggs, Freeman, and Yaffe".
According to Calhoun (2017), "Acetaminophen has traditionally been considered safe in all stages of pregnancy." Birth defects have not been attributed to acetaminophen after almost four decades of use worldwide.
Regarding NSAIDs, "With NSAIDs, adverse outcomes differ according to the trimester of exposure. They are generally considered Category B in the first two trimesters" (Calhoun, 2017). NSAIDs remain contraindicated after the 30th week due to premature closure of the ductus arteriosus. Aspirin and non-steroidal anti-inflammatory drugs should also be avoided in later pregnancy because of bleeding potential.
Butalbital, is an ingrediant in preparations such as "Fioricet", which contains acetominophen, caffeine and butalbital. Butalital has long been considered the abortive treatment of choice for migraine during pregnancy. As of 2016, there was a report of increased congenital heart defects in a single study. (Wells et al, 2016)
Regarding triptans, according to Calhoun, " It would thus appear appropriate for the FDA to admit that adequate meta-analyses and database re- views have demonstrated no increased risk of human fetal abnormalities with exposure to sumatriptan and to change its pregnancy category to B—but unfortunately, these categories no longer exist." It does appear that the evidence suggests that there is no increased risk of birth defects. Similarly, > a recent report suggested that there is no difference in pregnancy outcome when sumatriptan is used in the first trimester (Shuhaiber et al, 1998).
It is generally felt that no "ergots" should be used during pregnancy because of the danger of inducing early labor.
Regarding prevention medications, in pregnancy, the general approach is to avoid them. This also means stopping medications being used for prevention once a woman becomes pregnant. If there is a reasonable chance of pregnancy (i.e. a couple is "trying"), it also seems reasonable to stop medications as is consistent with safety.
If there is a pressing need for a migraine prevention medication, preventive medications can generally not be used until the third trimester. Then some clinicians use amitriptyline or imipramine as both have a long record of safety during pregnancy. These should be withdrawn 2 weeks prior to estimated date of delivery. Inderal (propranolol) may reduce cardiac performance during delivery, and should be avoided if possible for this reason. Presumably the same considerations apply to all other beta blockers.
Topiramate should not be used for migraine prevention during pregnancy because of a high incidence of cleft palate. (Mines et al, 2014).
Venlafaxine for migraine should be stopped prior to becoming pregnant. Briggs et al (2017) states that "Human studies suggest risk in 3rd trimester". A recent study also suggested risk during early pregnancy (Anderson et al, 2020).
It is also well known that sodium valproate should be avoided entirely in pregnancy when it is used solely for migraine. (Macfarlane and Greenhalgh. 2018)
Verapamil is felt by Briggs et al (2017) to be "compatible" with pregnancy.
Lactation commonly inhibits ovulation, and generally leads to an improvement in migraine during the postpartum period. The improvement is similar to that found during the 2nd trimester of pregnancy.
Generally speaking, these medications are judged in terms of their safety to the fetus.
Again, triptans are felt to be compatible or probably compatible with lactation, while ergots are not. Sumatriptan in particular is thought to be safe during lactation (Calhoun, 2017). Rizatriptan would probably not be safe.
According to Calhoun (2017), among Nsaids, ibuprofen is the preferred choice, while NSAIDs with long half-lives such as naproxam can accumulate in the infant.
Venlafaxine (for prevention of migraine) is generally thought to be safe in nursing mothers (see drugs.com site). However, Briggs et al (2017) list venlafaxine as "limited human data -- potential toxicity". Their reasoning appears to be based on worry (but no data) that venlafaxine might have a neurodevelopmental effect.
Topiramate is not considered to be safe while lactating due to "potential toxicity". (Briggs et al, 2017).
Beta blockers: The two listed below are thought to have the least risk.
- Propranolol is listed as "limited human data -- potential toxicity". However, in 2001 the American academy of pediatrics classified propranolol as compatible with breastfeeding (Briggs et al, 2017).
- Metoprolol, also was classified in 2001 bythe American academy of pediatrics as compatible with breastfeeding (Briggs et al, 2017).
- Beta-blockers that should probably be avoided are atanolol and nadolol because of relatively high milk levels.
Verapamil, according to Briggs et al (2017), is "probably compatible" with lactation.