to control other vascular risk factors, such as high blood
pressure, elevated cholesterol, and smoking.
In general, we ask patients to carefully evaluate their
lifestyle. Nutrition, hydration, exercise, and sleep are factors which need to be considered. We also ask the patients
to recognize stressful situations and consider use of stress
relaxation, meditation, yoga, or massage. Adequate sleep,
attention to sleep hygiene, and stress relaxation also
becomes paramount.
During pregnancy, we advise our patients about the
one-third rule. A third of the pregnant migraineurs
improve during pregnancy, one-third maintains the status
quo, and the remaining one-third experience an exacerbation of their headaches. Very rarely, migraines develop
for the first time during pregnancy. In general, patients
with menstrually-associated migraine improve during
pregnancy. It is believed that hormonal fluctuations are
probably the main trigger for migraine.
Migraine Treatment During Pregnancy
Three classifications for drug safety during pregnancy
have been established. The U.S. Food and Drug Administration (FDA) categorizes the drugs into Category
A through X (Table 1), Classifications have also been
developed in Sweden and Australia.
There is one additional category, “Pregnancy Category
N”, which is a transitional identification indicating that
the FDA has not yet classified the drug into a specified
pregnancy category.
Acute Treatment
Recently, a large observational prospective study was
conducted in Norway involving pregnant women. In
the Norwegian Mother and Child Cohort Study, 1535
pregnant women received triptans. This study does
provide some reassurance to women who may need to
continue to use triptans during pregnancy. These women
were compared to 373 migraine controls who had used a
triptan during the 6 months prior to pregnancy. During the first trimester, 90% of the approximately 1400
patients used a triptan. In this relatively large cohort of
pregnant patients exposed to the triptans during their
first trimester, no increased risk of malformations in the
fetuses was observed.
A pregnancy exposure registry is a study that collects
health information from women who take medicines
or vaccines while they are pregnant. The FDA does not
run pregnancy studies, but it keeps a list of all registries
that are current. Most pregnancy registries are sponsored
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HeadWise™
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Volume 3, Issue 3 • 2013
by pharmaceutical companies, and maintained by an
independent research company.
In general, we consult with a perinatologist and if
available, a pregnancy toxicologist, in order to consider
other risk factors such as maternal age, health, smoking,
alcohol or other drug use, to assist in decisions of whether
or not to continue the use of triptans during pregnancy.
Probably, sumatriptan has the largest pregnancy registry.
If a triptan is deemed low risk, we tend to recommend it
over those with higher risk to the fetus.
The largest available data on opiates and pregnancy are
based on retrospective exposure studies from the National
Birth Defects Registry (NBDR). In these studies, data
on over 17,000 cases were examined, with over 6000
controls, excluding mothers with exposure to street drugs,
preexisting diabetes, or malformations with less than
200 cases or <4 exposures. Of the mothers interviewed,
2.6% reported use of opiates during the month prior or
3 months into their pregnancy, while 2.0% of controls
reported a similar exposure. The predominant opiate
exposures were to codeine and hydrocodone (34.5%
each). A significant association was found between opiate
use and congenital heart defects, as well as spina bifida,
hydrocephaly, glaucoma or anterior chamber eye defects,
and gastroschisis. Gastroschisis is a congenital defect
characterized by a defect in the anterior abdominal wall
through which the abdominal contents freely protrude. It
is usually to the right of the umbilicus (belly button).
Finally, maternal obesity is another factor that needs
to be considered. Maternal obesity has been associated, in and of itself, with increased risk of neural-tube
defects and congenital heart defects. A neural tube
defect (NTD) is an opening in the spinal cord or brain
that occurs very early in human development and fails
to close. Unfortunately, few studies have examined the
effect modification based on obesity, which may be due
to the pharmacokinetics of many of the medications.
The term, pharmacokinetics, describes what happens in
the body once a drug is administered. This includes the
mechanisms of absorption and distribution, as well as the
chemical changes (metabolism) of the substance in the
body and how it is excreted from the body.
Pregnancy Planning in the Migraineur:
Preventive Therapy
The biggest concern with preventive medication use
during pregnancy is the risk of congenital malformations.