Symptoms related to sleep (eg, insomnia, sleep apnea,
hypersomnia, and parasomnias) are more common in pregnant women than in
nonpregnant women. Pregnant women are most likely to snore and to have
insomnia and daytime sleepiness. A variety of factors may contribute to
this increase in symptoms, including weight gain, hormonal changes,
nutritional stress, and nocturnal discomfort.
[33]
Insomnia
Insomnia
is most prevalent in the first and third trimesters and affects a
substantial minority of pregnant women. Causes include urinary
frequency, low back pain, nocturnal cramps, fetal movements, and restless legs syndrome (RLS) or periodic limb movements of sleep.
Urinary frequency often occurs early in pregnancy and may result in repeated bouts of nocturia.
Low back pain is a common symptom among pregnant women. The
weight of the enlarging uterus stresses the spine and changes lumbar
posture. Sleeping position may have to be changed to one that minimizes
backache. Specially shaped pillows have been recommended and offer some
benefit. Water exercises, physical therapy, and acupuncture may also
reduce discomfort, improve function, and lessen insomnia.
Nocturnal cramps occur more frequently during pregnancy than
in other stages of life. The cause of these painful, sleep-disrupting
attacks usually cannot be determined. Several trials of vitamin and
mineral supplements have been published, but little benefit from such
treatments is documented. The available data give greatest support to
the use of magnesium salts to decrease cramps.
Fetal movements become increasingly prominent as pregnancy
progresses, and they may contribute to nocturnal arousals in certain
patients.
RLS may occur throughout life but is unusually prevalent during pregnancy. In
this disorder, the patient reports a distinctly unpleasant, nearly
continuous urge to move her legs late in the day and at night. The
symptoms can be a major obstacle to falling asleep. Once asleep, a
patient may have periodic leg movements that can cause several arousals.
Data from epidemiologic and other investigations support the
notion that iron deficiency may play a role in the genesis of RLS. Iron
is a cofactor in the endogenous production of dopamine in the central
nervous system (CNS). Dopamine, in turn, plays a role in modulating
movement. The altered dopaminergic balance can result in restlessness.
This is seen in association with Parkinson disease and in the akathisia
that may accompany the use of neuroleptic drugs, which are known to
block dopamine receptors.
Folate is another nutrient that may play a role in the
prevention of RLS. In a group of pregnant women, those with low serum
folate levels were most likely to have restless legs.
Dopamine receptor agonists have been highly effective in
relieving RLS, but their safety during pregnancy has not been
demonstrated; other proven treatments include narcotics,
benzodiazepines, certain antiepileptic drugs (AEDs), and clonidine. These agents are associated with varying levels of risk to the fetus (see Table 3 below).
Table 3. Risks of Drug Therapies for Restless Leg Syndrome in Pregnancy (Open Table in a new window)
Drug Class |
Generic Name |
level of Risk in Pregnancy |
Dopaminergic |
Carbidopa-levodopa |
C |
Bromocriptine |
B |
Pergolide (removed from US market March 29, 2007*) |
B |
Pramipexole |
C |
Ropinirole |
C |
Opioid |
Oxycodone |
B |
Propoxyphene |
C (D for long-term use) |
Tramadol |
C |
Benzodiazepine |
Clonazepam |
D |
Diazepam |
D |
Lorazepam |
D |
Antiepileptic |
Gabapentin |
C |
Carbamazepine |
D |
Alpha-agonist |
Clonidine |
C |
* Pergolide was withdrawn from
the US market on March 29, 2007, because of heart valve damage
resulting in cardiac valve regurgitation. It is important not to stop
pergolide abruptly. Healthcare professionals should assess patients’
need for dopamine agonist therapy and consider alternative treatment. If
continued treatment with a dopamine agonist is needed, another dopamine
agonist should be substituted for pergolide. |
Because RLS has a benign prognosis and often resolves after
pregnancy, most women are reluctant to receive pharmacologic treatment.
Increased supplementation of iron and folate may be the best approach.
In addition, because the serum ferritin level may not directly reflect
the availability of iron in the CNS, iron supplementation to achieve a
ferritin level above the minimal normal level should be considered.
Additional folate intake beyond the recommended daily allowance of 400
µg may also be warranted.
Sleep apnea
Although elderly men have the risk of obstructive sleep apnea, sleep-disordered breathing may also occur in pregnant women. The
prevalence of loud snoring is reported to increase during the late
months of pregnancy. Women who gain excessive weight or develop fluid
retention may be at particular risk for reduced airflow (ie, apneic and
hypopneic events). Such irregularities in breathing degrade the quality
of nighttime sleep and may lead to daytime sleepiness.
Possible nocturnal oxygen desaturation is another issue for
pregnant women, especially during rapid eye movement (REM) sleep. REM
sleep typically produces a generalized loss of muscle tone (except in
the diaphragm). Consequently, patients with restrictive lung disease may
breathe at abnormally low lung volumes during REM sleep. When lung
volumes are low, blood may be shunted through underventilated lung
tissue, and oxygen desaturation may result. The abdominal distention
caused by a gravid uterus may produce or add to a preexisting
restriction.
Sleep apnea is a recognized risk factor for hypertension. It
may cause recurrent activation of the sympathetic nervous system in
response to airway obstruction and hypoxemia. Women with preeclampsia
are most likely to have narrow upper airways and to be snorers; this
observation suggests that increased upper airway resistance or the
resultant snoring or apneas may contribute to pregnancy-induced
hypertension. A greater degree of sleep-disordered breathing is seen in
in preeclamptic women than in nonpreeclamptic women.
Pregnant women who have an elevated apnea-hypopnea index can
be successfully treated with nasal continuous positive airway pressure
(NCPAP) therapy, and their blood pressure can be decreased.
Hypersomnia
Daytime sleepiness is another common symptom during
pregnancy, but its severity and effect on well-being have not been
thoroughly studied. Hormonal changes are suspected to be a contributing
factor in the first trimester. After this period, disrupted nighttime
sleep may be a substantial factor. Sleep apnea may be the cause in an
obese woman who snores.
Particularly in the presence of hypertension, nocturnal
polysomnography (multichannel sleep study) may be warranted to diagnose
the disorder. NCPAP therapy may be started if indicated, depending on
the severity of the condition.
Patients with previously diagnosed narcolepsy or idiopathic
CNS hypersomnia may become pregnant and require changes in their
treatment. Commonly used stimulants have not been shown to be safe in
pregnancy, and these agents should be withdrawn from most patients
before conception. An inability to drive safely and an overall decline
in functional status may result. For the stimulants dextroamphetamine, methylphenidate, and modafinil, the level of risk to the fetus is category C.
Since 2002, sodium oxybate
(gamma-hydroxybutyrate; GHB) has been available to treat narcolepsy. It
is a highly sedating compound that is known as a drug of abuse. Sodium
oxybate is taken only at night and reduces both cataplexy and daytime
sleepiness through unknown mechanisms. The absence of teratogenicity in
animal studies has led to it being classified as category B.
Thus, sodium oxybate might be preferable to stimulants during
pregnancy, but whether this is so has not been established in clinical
trials. Because of its potential for respiratory suppression, sodium
oxybate could be harmful to pregnant women with sleep apnea, hypoxemia,
or hypoventilation. The maximum recommended dosage is a daily sodium
load of 1.6 g, which may be undesirable in pregnant women with edema or
hypertension.
Parasomnias
Sleep walking, night terrors, and other parasomnias
may occur in women of childbearing age. A few systematic studies have
been conducted to investigate the effect of pregnancy on these
disorders. Data on whether symptoms may increase or decrease during
pregnancy are conflicting. Because benzodiazepines are often given to
treat parasomnias and because they may be harmful to the fetus, an
attempt should be made to withdraw these agents before conception or, in
unplanned pregnancies, early in the first trimester.
Multiple Sclerosis
Effects of multiple sclerosis on pregnancy
Complications of pregnancy are generally thought to affect women with multiple sclerosis (MS) no more often than they affect women in the general population. This belief extends as far back as 1948 and is supported by data from numerous subsequent studies of fertility, pregnancy, and delivery. Data
also suggest that the risk of spontaneous abortions, congenital
malformations, stillbirths, and complications of pregnancy (eg,
preeclampsia, premature delivery) is not increased.
Although many findings weigh against the idea that there is a
higher risk of low birth weight in infants of mothers with MS, a
retrospective study of the Norwegian national registry showed an
increased rate of neonates being small for their gestational age (SGA). These
neonates had a reduced mean birth weight and length but normal head
circumference. The etiology was unclear, though the subtle morphologic
changes in the pelvic organs of women with MS may result in suboptimal
intrauterine conditions that influence fetal development.
The data also suggested an effect on deliveries. Although
the number of planned cesarean deliveries increased, women delivering
vaginally had an increased incidence of slow labor progression
necessitating interventions. This result may have been partly due to
perineal weakness and spasticity and fatigue related to MS.
These findings were countered by those of a 3-year
prospective study that reported normal distributions of weight and head
circumferences in babies born to mothers with multiple sclerosis. Rates of infant death, congenital anomalies, and cesarean deliveries were also similar to those of the general population.
The reasons for the discrepancies in these studies are
unclear. It is certainly possible that differences in the severity and
localization of disease in the patient populations of each study could
play a role in the outcomes, particularly if perineal and bladder
involvement differed. Factors increasing the frequencies of pelvic
infections may also play a role.
Although MS is unlikely to have a serious effect on
pregnancy, each patient should be evaluated on an individual basis.
Patients with clinically significant bladder and perineal involvement
and excessive fatigue should be counseled about possible interventions
that may help facilitate delivery.
Effects of pregnancy on multiple sclerosis
An Israeli study of 338 women conducted to evaluate the MS
relapse rate during each trimester of pregnancy and 6 months after
delivery reported that of 199 completed pregnancies in 66 women, 85 were
accompanied by relapses (20 during pregnancy, 65 post partum). The relapse rate was definitely reduced in the third trimester.
In a later study, Salemi et al reported a significant reduction in the relapse rate during pregnancy. Using
a questionnaire, the investigators collected information concerning
patient age at the onset of MS, duration of disease, number of relapses
during the prepregnancy period, number of relapses during pregnancy, and
number of relapses during the first 3 months after delivery. Out of 350
patients, 70 had 98 pregnancies.
The Pregnancy in Multiple Sclerosis (PRIMS) study was the first multicenter prospective study of MS in pregnant women. In
this study, the relapse rate declined by approximately 70% during the
third trimester as compared with the rate in the year before conception.
The researchers evaluated 254 women with relapsing-remitting MS during
and after 269 pregnancies. Patients were examined at 20, 28, and 36
weeks’ gestation to determine the relapse rate in each trimester.
Roullet et al reported that MS relapses occurring during
pregnancy tended to be mild, resulting in minimal or no residual
deficits. They
examined the severity of relapses in 125 French women who were followed
via an MS clinic over 10 years and who had a total of 32 full-term
pregnancies.
Patients with MS appear to fare better when they are pregnant
(particularly in the third trimester) than when they are not, with a
decrease in the number and severity of relapses. Some authors claim that
the suppression of MS seen during pregnancy may be more potent than
that achieved with currently available treatments.
Nevertheless, the decision whether to forgo treatment with
immunomodulatory agents must be made on an individual basis. Given the
potential risks these treatments pose for pregnant women, the decision
to treat should be reserved only for exceptional cases (see Treatments
during pregnancy).
Postpartum period
In the first 3 months after delivery, MS relapses appear to
increase in frequency and severity, though they return to their
prepregnancy level afterward. Because this increase is offset by the
decrease in MS activity during pregnancy, pregnancy does not seem to
change the overall course of the disease from the perspective of
disability.
Patients with relatively severe disease before and during
pregnancy appear to be at greatest risk for relapses in the postpartum
period. No other single predictor was identified. In these patients,
therapies that may reduce the likelihood of relapses should be
considered.
In an early study, Millar et al evaluated 45
pregnancy-associated relapses in 170 pregnancies and reported that 39
women experienced relapses in the postpartum period.
Worthington et al observed that relapses were most frequent
during the first 6 months after pregnancy and that fewer relapses than
expected occurred in postpartum months 6-24. The
investigators conducted a 3-year prospective study of the level of
disability, severity, and distribution of relapses in 15 women with MS
diagnosed before pregnancy, using 22 nulliparous women with the disease
as control subjects.
Salemi et al retrospectively determined that the relapse rate
increased in the first 3 months after delivery, though the change was
not statistically significant.
In a study of 338 women, Korn-Lubetzki et al found that
postpartum exacerbations of MS were 3 times more common in patients than
in control subjects.
In the Pregnancy in Multiple Sclerosis (PRIMS) study, the
postpartum relapse rate increased by approximately 70% and then returned
to the prepregnancy rate. Neither breastfeeding nor epidural analgesia affected the rate of relapse or progression of disability.
In a study of 227 women enrolled in the PRIMS study for an
additional 2 years after delivery, Vukusic et al reported that women
with increased disease activity in the year before pregnancy and those
who had additional relapses during pregnancy were most likely to have
postpartum relapses. The
investigators did not find a single predictor (including breastfeeding
or epidural anesthesia) that helped in accurately identifying women with
MS who would have relapses in the first 3 months after delivery.
In the second postpartum year, the relapse rate was similar to that of the year before pregnancy. In addition, pregnancy, delivery, and the postpartum period did not ultimately increase overall disability from MS.
Roullet et al also found that relapses were most severe
during the postpartum period, as reflected by a change of more than 1
point in the Expanded Disability Status Scale (EDSS) score. Worthington et al confirmed this result, finding that relapses were most severe during the first 6 months after pregnancy. No
overall significant differences in the severity of relapses were found
between patients and control subjects, as measured by using the median
EDSS score after the pregnant and postpartum periods.
Epidural anesthesia did not appear to affect the rate of relapse or progression of disability in either the PRIMS trial or its 2-year extension. This
finding suggests that despite anecdotal reports suggesting otherwise,
epidural analgesia is safe and does not carry a significant risk when it
is used for deliveries in patients with MS.
Breastfeeding
Breastfeeding does not appear to have a notable effect on the
activity of MS. However, it does lower the incidences of infantile
illnesses, which suggests that it confers some protection on the infant.
This finding potentially supports the consideration of breastfeeding
and the delay of immunomodulating therapy until breastfeeding is stopped
in patients with MS. These potential benefits should be weighed against
the risks of delaying treatment on a case-by-case basis.
In a questionnaire-based retrospective study that evaluated
the onset of MS, relapse frequency, and breastfeeding in 438 women, half
of the patients breastfed their children for a mean of 6.3 months, but
the relapse rate in the breastfeeding group was not significantly
different from that in the control subjects.
In addition, the mean time to relapse was not delayed with
breastfeeding; in fact, 69% of relapses in the breastfeeding group
occurred while the patient was still breastfeeding. The study data suggested that breastfeeding did not extend the protective effects of pregnancy on exacerbations of MS.
Indeed, Vukusic et al reported that women who chose to breastfeed had fewer relapses than other women did. However,
the investigators also found that the women who chose to breastfeed had
relatively mild disease. Conversely, women with active disease (and
additional relapses) chose not to breastfeed.
In a study that assessed the incidence of various infantile
illnesses at age 6, 9, and 12 months in the children of 140
breastfeeding mothers and 35 nonbreastfeeding mothers, the infants who
were not breastfed had significantly higher incidences of otitis media,
lower respiratory tract illnesses, constipation, milk intolerance, and
allergies.
[50]
Treatments during pregnancy
How best to treat pregnant women with MS remains
controversial. Although some claim that the suppression of MS during
pregnancy is more potent than that achieved with currently available
therapies for the disease,
[46] it is not clear whether this claim holds true in all cases.
Interferons (category C)
Although interferon beta-1a (IFN-β1a) and interferon beta-1b
(IFN-β1b) are category C agents, sufficient data are available from
published reports to indicate that they should not be used in pregnant
patients, because they impose a high frequency of serious risks on the
fetus.
In a rhesus monkey model, high doses of IFN-β1a were not teratogenic but had a dose-dependent abortive effect. In
a longitudinal, 3-pronged cohort study involving a group exposed to
IFN-β1a and IFN-β1b, a disease-matched unexposed group, and a healthy
control group, mean birth weight decreased and rates of miscarriages and
stillbirths increased in the exposed group as compared with the control
group (39.1% vs 5%). Two major malformations were also identified: an X
chromosomal abnormality and Down syndrome.
In another study, 41 pregnancies involving IFN-β1a exposure
resulted in 20 healthy full-term infants, 1 healthy premature infant, 9
induced abortions, 8 spontaneous abortions, and 1 fetal death; 1 patient
had hydrocephalus, and another was lost to follow-up. These
findings were in stark contrast to those of the 22 control subjects,
who were exposed to IFN-β1a before, but not during, pregnancy. This
control group included 20 full-term healthy infants, 1 healthy premature
infant, and 1 infant with a birth-related complication (Erb palsy).
Glatiramer acetate (category B)
An abstract presented at a meeting of the American Academy of Neurology (AAN) in 2003 suggested that glatiramer acetate
imposes no substantial risks in pregnancy and has no abortifacient or
teratogenic effects. This drug is not known to be excreted in breast
milk. Evidence suggests that glatiramer acetate might be safe in
pregnancy and breastfeeding. However, caution should be exercised if one
decides to treat patients with this drug.
Mitoxantrone (category D)
Mitoxantrone
has been associated with low birth weight and abnormal fetal kidney
development in animal studies. Rats treated with mitoxantrone had an
increased incidence of preterm labor. Because of its known risk in pregnancy, mitoxantrone should not be used in pregnant patients.
Intravenous immunoglobulin (category C)
Orvieto et al suggested that intravenous immunoglobulin (IVIg) has no known teratogenic effects. It
also appears to have no effects on the immune system of the fetus or
newborn. If necessary, treatment with IVIg may be considered, though the
potential risks must be carefully assessed.
Azathioprine (category D)
Despite azathioprine’s category D rating, some believe that
this agent is potentially useful for treating MS in pregnancy. Although azathioprine
crosses the placenta, the fetus lacks the enzymes that convert the drug
into its active metabolites; this lack may protect the fetus from the
potential teratogenic effects of azathioprine. Nevertheless, given the category D rating, the use of this drug in pregnancy should be avoided if at all possible.
Methotrexate (category X)
Methotrexate is known to be capable of causing malformations and abortifacient effects. It has a category X rating and should not be used in pregnant patients.
Cyclophosphamide (category D)
Cyclophosphamide is teratogenic in animals, but whether it is also teratogenic in humans has not been clearly determined. Nevertheless, it is a category D agent and therefore should be avoided in pregnant patients.
Corticosteroids (methylprednisolone) (category C)
The PRIMS study included 16 pregnant women who received
corticosteroids; no adverse effects were noted in either the patients or
their children. Corticosteroids (eg, methylprednisolone)
may be safe in pregnancy. However, use of these drugs in pregnant
patients should be considered carefully and avoided unless deemed
necessary.
Possible postpartum treatments
There is some evidence to suggest that corticosteroids and IVIg might be beneficial in the postpartum management of MS.
Corticosteroids (methylprednisolone)
In one study, 22 patients from 1996 to 1998 who received no
treatment for MS after delivery were compared with 20 patients from 1999
to 2001 who were treated with 1 g of intravenous (IV) corticosteroids
monthly for the first 6 months post partum. Although
the mean relapse rate increased during the first 3 months in both
groups, it was higher in the untreated group than in the treated group
(2 ± 0.66 versus 0.8 ± 0.41).
The finding from this study suggests that prophylactic
treatment with IV corticosteroids may be beneficial during the first 3
months after pregnancy. To the authors’ knowledge, however, no studies have adequately assessed the safety of this approach in breastfeeding women.
Intravenous immunoglobulin
IVIg treatment may be effective in reducing the incidence of
pregnancy- and postpartum-related relapses. Again, the potential risks
and benefits must be carefully assessed before treatment is started,
especially because the medication falls into category C. Its safety in
breastfeeding women is unknown.
In a study of 9 patients with a history of postpartum acute
exacerbations of MS who were treated with IVIg for 5 consecutive days in
the first week after childbirth and at 6 and 12 weeks afterward, none
had a relapse during the 6 months after delivery.
Achiron et al retrospectively studied IVIg treatment during
pregnancy and the postpartum period in 108 pregnant patients with
relapsing-remitting MS and found a positive effect. The
subjects were assigned to an untreated group, a group treated with IVIg
in the first week after delivery with booster doses after 6 and 12
weeks, or another group treated continuously with IVIg during and after
pregnancy.
Comparison of relapse rates for patients treated with IVIg
for the entire pregnancy and relapse rates in the untreated group
revealed a positive effect for the former, as follows :
-
First trimester - 0.43 versus 0.72
-
Second trimester - 0.15 versus 0.61
-
Third trimester - 0.0 versus 0.41
-
Postpartum period - 0.28 versus 1.33
Relapse rates also decreased in patients treated with IVIg
only after delivery (0.58) as compared with untreated patients (1.33).
No significant adverse events were associated with IVIg treatment in
patients or newborns.
Haas reported that the exacerbation rate after delivery in IVIg-treated individuals was reduced by 33%. IVIg
was administered within 3 days after delivery and then monthly to
patients thought to be at high risk for exacerbations. They were
compared with patients in the PRIMS study, who, for this study, served
as control subjects.
Myasthenia Gravis
Autoimmune myasthenia gravis (MG) is an uncommon disease of
the neuromuscular junction characterized by striated muscle fatigue and
weakness. MG frequently affects young women of childbearing age (20-40
years of age), and pregnancy creates potential risks for both the mother
and the fetus. (See
Myasthenia Gravis and Pregnancy.) During pregnancy, the course of
disease is unpredictable. In a series of 69 pregnancies in 65 women with
MG who were treated in a single obstetrics department, 15% had
deterioration during pregnancy, and 16% had deterioration during the
puerperium. In
a report of 64 pregnancies in 47 women with MG, 39% of those treated
improved, 42% were unchanged, 19% had deterioration, and 17% of those
not receiving therapy had deterioration.
[65] Myasthenic
symptoms of 28% of women worsened after pregnancy. Therefore,
successful management necessarily involves recognizing the potential for
myasthenic crisis, optimizing anticholinesterase or
immunosuppressivemedicationtreatment, and preparing for the possibility
of transient neonatal MG. The challenging care of a woman with MG who is
contemplating pregnancy should begin with careful planning and the
collaboration of obstetricians and neonatal intensive care specialists.
Counseling should address current knowledge, risks, and available
treatments. Women with MG who decide to become pregnant should receive
prenatal care from providers with experience in treating this disease,
and delivery should be performed at a hospital that can manage any
complications that may arise. Management
of pregnancy and delivery The risks and benefits of continuing
medication or other immunosuppressive therapy should be discussed, and
counseling should begin when the pregnancy is planned. Treatment of MG
should be optimized, and clinical improvement should be maximized. The
need for immunosuppressant treatment depends on the severity of illness
and should be modified according to the duration andseverity of
thepatient’s symptoms of MG. If possible, physicians with experience in
treating patients with this disease should perform the delivery at a
hospital with the capability to treat both women and infants with
complications of MG. In the 1967-2000 Medical Birth Registry of Norway, a
population-based cohort study, the potential for cesarean delivery
doubled in 127 births by 79 mothers with MG (17.6%) as compared with a
reference group (8.6%). The
number of births requiring medication to induce labor was not
increased. Serious birth defects occurred in 5 children of mothers with
MG, but the rate of such defects was not significantly greater than that
of a reference group. Preterm rupture of the amniotic membranes was the
only complication that occurred more frequently in the MG group than in
a comparison group. Rates of neonatal mortality, birth weight, or prematurity did not differ. Pregnancy did not worsen the long-term outcome of MG. Cesarean
delivery is recommended ifit isnecessary for obstetric reasons, and
regional anesthesia is safe with correct drug selection. To
reduce the potential for adverse effects on the fetus,
immunosuppressive medication should be discontinued if possible, or the
dose should be minimized. However, little information about this topic
is available in the literature. Some information can be derived from the
treatment of patients with other autoimmune disorders, but separating
the effects from the potential risks of the treated illness is
difficult.
Prednisone or prednisolone
is associated with a slightly (< 1%) increased risk of cleft palate.
High-dose corticosteroids may be associated with premature rupture of
amniotic membranes. Methotrexate may be associated with fetal malformations and thus is not recommended for use during childbearing years. Although
women taking azathioprine have generally been advised against
pregnancy, no teratogenicity or specific malformation pattern has been
definitively demonstrated with therapeutic doses in humans.
In a retrospective review of pregnancy outcomes, infants
exposed to azathioprine were at risk for the development of reversible
leukopenia, anemia, thrombocytopenia, reduced immunoglobulin levels,
infection, or thymic atrophy. Babies born to mothers treated with azathioprine have an increased risk of myelosuppression and immunosuppression.
Cyclosporine increases the risk of low birth weight, prematurity, and spontaneous abortions. Nausea and vomiting early in pregnancy may interfere with pyridostigmine
dosing. Drug schedules may have to be altered because of increased
renal clearance, expanded blood volume, and erratic gastrointestinal
absorption.
Discontinuance of maternal immunosuppressants can either
worsen or improve MG. If needed, plasma exchange or human intravenous
immunoglobulin (IVIg) therapy may be effective and can be safely
administered during pregnancy. In theory, plasma exchange can induce
premature delivery through large hormonal shifts.
Although MG does not directly affect the uterine smooth
muscle, the striated abdominal muscles that contract with the effort of
delivery during the second stage of labor may fatigue and weaken more
easily than they would if the disease were not present.
Acetylcholinesterase drugs should probably be given
parenterally because of their unpredictable oral absorption.
Neuromuscular blockers may exaggerate and prolong muscular weakness and
should be avoided if possible. Epidural anesthesia is considered
relatively safe for vaginal and cesarean deliveries.
Magnesium sulfate is used to prevent seizures in patients
with preeclampsia, to treat eclampsia, and to prevent preterm birth in
patients with preterm labor; this drug can precipitate weakness by
interfering with neuromuscular transmission. Maternal deaths are
reported with its use to treat MG in women with preeclampsia.
Consultation with an anesthesiologist should be considered for all pregnant patients with MG.
Complications in newborns
Neonatal MG may result from passive transplacental transfer
of antibodies to the nicotinic acetylcholine receptor from the
myasthenic mother to the fetus. However, not all infants with detectable
levels of antibodies to acetylcholine receptor develop neonatal MG.
The severity of symptoms varies, ranging from mild hypotonia
to respiratory distress. Clinical symptoms develop in the first few
hours after birth and usually resolve within 2-3 weeks. In
the Medical Birth Registry of Norway, 21.3% of children of mothers with
MG needed transfer to intensive care units (ICUs), compared with 2% of
the reference group. Other studies have shown a neonatal MG incidence of
10-21%, and neonatal disease was reported in 4% (but probably affected
12%) of the Norway registry cohort.
Children of mothers with MG require careful observation in
the first few days after birth, and symptoms may respond to
anticholinesterase medication. Women with MG should deliver in a facility with a neonatal ICU.
Arthrogryposis multiplex congenita, characterized by multiple
joint contractures in utero, occasionally complicates the pregnancy of a
mother with MG. Circulating antibodies may inhibit the function of
fetal acetylcholine receptors, with little effect on adult acetylcholine
receptor function, and may be responsible for this condition.
A high ratio of antifetal to antiadult muscle
antiacetylcholine receptor antibodies is predictive of neonatal MG in
the first child of a mother with the disease. Elevated
alpha-fetoprotein levels may inhibit acetylcholine antibody binding
capacity, and this may explain the delay to onset of neonatal MG
symptoms after birth.
Cerebrovascular Disease
Stroke is the third leading cause of death and the primary
cause of adult disability in the United States. It may be broadly
classified as either ischemic or hemorrhagic. Although cerebrovascular
disease is thought to be uncommon in pregnancy, it is an important
source of maternal and fetal morbidity and mortality, causing 3.5-26
cases of neurologic dysfunction per 100,000 deliveries, and is
associated with more than 12% of maternal deaths.
The incidence of stroke during the childbearing ages alone is
10.7 cases per 100,000 women. Some authors have questioned whether the
risk of stroke increases in association with pregnancy itself ; however, evidence suggests that the postpartum period is associated with an increased risk of ischemic stroke.
Ischemic stroke
Ischemic strokes account for 85% of all strokes. Causes
of ischemic stroke in pregnancy may be divided into 2 general
categories: pregnancy-specific etiologies and stroke-in-the-young
factors.
The first category includes the following:
-
Preeclampsia and eclampsia – These are present in 24-47% of ischemic strokes and 14-44% of intracranial hemorrhages
-
-
-
Peripartum cardiomyopathy
-
Postpartum cerebral angiopathy – This rare and reversible
condition causes narrowing of the blood vessels, which can lead to
ischemia
Causes of stroke in a young person include the following:
-
Atherothrombotic etiologies
-
-
-
Other vasculopathy (eg, fibromuscular dysplasia [FMD], dissection, or arteritis)
-
-
-
-
Some causes in this category are less common in stroke than
in other settings; they occur most frequently in relatively young women.
Lupus
Systemic lupus erythematosus
(SLE) is one of the disorders that is most common in women. SLE is
associated with cerebrovascular events arising from hypercoagulability
associated with antiphospholipid antibodies or vasculitis. Thrombus may
have a cardiac origin or may come from within the intracranial
vasculature.
[76]
Antiphospholipid antibody syndrome and hypercoagulable states
Antiphospholipid antibody syndrome is associated with stroke
in young women and with SLE and other collagen-vascular diseases. The
patient’s medical history is important for diagnosing the disorder and
should include a pertinent history of spontaneous abortions or
intrauterine fetal demise (especially if multiple), thrombotic events, a
family history of stroke or antiphospholipid antibody syndrome, and
thrombocytopenia. Treatment usually consists of anticoagulation. (See Antiphospholipid Antibody Syndrome and Pregnancy.)
Other hypercoagulable states that occur in young women include the following:
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Antithrombin III deficiency
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Protein C or S deficiencies
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Resistance to activated protein C
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Plasminogen and plasminogen-activator deficiency
Because pregnancy itself results in a hypercoagulable state,
the risk for thrombotic events increases in patients with a known
preexisting hypercoagulable condition. These disorders should also be
considered in young women with stroke and should be investigated if
suspected.
Vasculopathy
Vasculitis is a rare condition that may occur in women of
childbearing age and may result in stroke if it involves the cerebral
vessels. In addition to focal symptoms of ischemia (stroke), cerebral
vasculitis may cause nonfocal symptoms such as headache and
encephalopathy. If suspected, particularly in the setting of known
systemic vasculitis, the patient should be evaluated with appropriate
laboratory and imaging studies. Primary central nervous system (CNS)
vasculitis is extremely rare.
Other forms of vasculopathy have been related to stroke in
females of childbearing age. This category of noninflammatory vascular
disease includes the following:
Arterial dissection causes symptoms of stroke secondary to
embolic fragments from the dissection site. Potential causes of a
dissection include FMD, trauma, hypertension, and spontaneous
etiologies. Treatment for vasculopathy is disease-specific and may
involve anticoagulation or surgical intervention.
Migraine headaches are common in young women and can be
associated with stroke, but these instances are rare. It is a diagnosis
of exclusion.
Cerebral venous thrombosis
Cerebral venous thrombosis (CVT) can cause symptoms of focal
dysfunction that mimic those of ischemic stroke. Because of the
hypercoagulable state during pregnancy, CVT is more common at this time
than at others. The postpartum period has the highest risk for CVT. One
study demonstrated that the risk of intracranial venous thrombosis was
11.66 cases per 100,000 deliveries. Treatment of CVT usually consists of anticoagulation and close monitoring.
Drug use
Use and abuse of legal and illegal drugs have also been
associated, probably causally, with ischemic stroke and intracerebral
hemorrhage. The drugs most specifically related to strokes include the
following:
These drugs may cause stroke by means of several mechanisms
(eg, hypertensive surges, arterial vasospasm, arrhythmias,
hypercoagulopathy, and embolization of diluent particles). Treatment
should be focused on stopping use of the drug and on rehabilitation.
Hemorrhagic stroke
Women at risk for intracerebral hemorrhage in pregnancy are
those with eclampsia, vasculitis, or an aneurysm or vascular
malformation. High blood pressure is the most important risk factor for
intracranial hemorrhage in pregnancy. Prevention is the key. Blood
pressure should be monitored closely during pregnancy.
Clinical evaluation
History and physical examination
Obtaining a history and performing a physical examination are
important aspects of evaluating the type of cerebrovascular event that
may have occurred. Important historical points include pain (eg,
headache or neck pain), trauma, fluctuating neurologic symptoms,
seizures, mental status changes, recent fevers, and drug use.
A complete history should include a medical history of
previous stroke or risk factors for stroke, spontaneous abortions,
collagen vascular disease, and a family history. In addition, a history
of complications that developed during the current and previous
pregnancies should be obtained. The patient should undergo a complete
physical examination, including funduscopic, cardiovascular, skin, and
full neurologic examinations.
Diagnostic imaging
Imaging studies are required, and several options are
available. Computed tomography (CT) is the most useful study for ruling
out acute hemorrhage; it is also useful for evaluating ischemic stroke.
CT angiography (CTA) and CT venography (CTV) can also be useful for
evaluating the cerebral vasculature. CT studies produce results quickly,
but they also pose a small radiation risk to the fetus. Evaluation of
bleeding from ruptured intracranial aneurysms or arteriovenous
malformations (AVMs) may require extensive imaging, including cerebral
arteriography.
Magnetic resonance imaging (MRI) is useful for evaluating
stroke in a pregnant patient. It does not carry the risk of radiation
exposure, and the contrast material required for some studies is
associated with few reports of adverse reactions, unlike the contrast
material used for CT studies. Although MRI takes longer to perform than
CT does, it offers a more detailed view of the brain tissue (especially
the posterior fossa). In addition, the diffusion-weighted images allow
greater accuracy in the diagnosis of acute ischemic events.
Other diagnostic studies that may be used to evaluate a
patient with ischemic stroke include carotid Doppler imaging,
transesophageal (TEE) or transthoracic echocardiography (TTE),
electrocardiography (ECG), and, occasionally, transcranial Doppler
imaging.
Laboratory tests
The choice of laboratory studies depends on the mechanism of
the stroke and on whether the arterial or the venous system is involved.
Studies may include the following:
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Hemoglobin electrophoresis
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Fasting homocysteine level determination
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Anticardiolipin or antiphospholipid antibody tests
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Thrombin time determination for dysfibrinogenemia and for factor V Leiden
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Prothrombin G20210A mutation tests
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Protein C or S tests – Note that protein S activity is
decreased during pregnancy; if possible, the protein study should be
performed 6-8 weeks after delivery
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Other studies may be indicated to investigate for SLE, other causes of vasculitis, and other systemic diseases.
Differential diagnosis
The differential diagnosis of stroke in young women includes
seizure, brain tumor, reversible posterior leukoencephalopathy (RPLE),
multiple sclerosis (MS), and migraine. In appropriate settings,
infectious causes (eg, Lyme disease and bacterial endocarditis) should
be considered.
Treatment
Treatment of stroke may minimize neuronal damage and is aimed
at preventing recurrences. In pregnancy, factors such as maternal risk
versus expected benefit and the level of fetal risk must be taken into
account. The stroke etiology also must be considered when determining
the best treatment.
Ischemic stroke
Tissue-type plasminogen activator (tPA)
is a category C agent in pregnancy. Its effects on humans and animals
during pregnancy have not been adequately evaluated, and at this point,
it is considered to be contraindicated. (See Thrombolytic Therapy in Stroke.)However,
recent reports of its use have led to reconsideration of this position.
TPA is a large molecule (7200kDa) and does not cross the placental
barrier. There are no teratogenic effects in short-term studies in
animals, no tumorigenicity in rodents, no mutagenicity or production of
chromosomal aberrations in human lymphocytes, and in rabbits no maternal
or fetal toxicity at 1mg/kg dosage. Three publications reporting on
treatment of 8 mothers provided encouraging outcome data. There
was good neurological recovery in most mothers. One patient also had IA
angioplasty, which led to dissection, amalignant MCA infarct, and
death. One patient sustained an intrauterine hematoma that was drained.
Fetal outcome in 5 babies was good. In two early cases medical
termination of pregnancy was opted for, and one child died with the
mother.
The current recommendations, based on expert opinion, are
that treatment decisions should be made balancing the natural history –
prognosis without tPA treatment and the benefit of treatment - taking
into consideration the risks of treatment.
Use of IV tPA can be considered in a pregnant patient. The
chief risk to the mother is a symptomatic intracranial bleed, which is
lower in individuals < 60 years: 2.8%, and a bleed eslewhere. To
date, there has not been a demonstrated risk to the fetus with IV tPA.
Despite in vitro concerns, iodinated contrast seems safe to use during
pregnancy. IV contrast does not pose a risk to the fetus.
Although other interventional techniques are being developed
to treat acute stroke, information about treating the pregnant patient
with stroke with these modalities is limited. When any of these
modalities is considered in a pregnant woman, the known risks of
withholding treatment must be balanced against the unknown risks of
treatment.
The stage of the pregnancy (ie, the gestational age) likely
factors into the considerations. From a dosing standpoint, targeted
intra-arterial treatment might be safer than other routes, but it
presents radiation risks to the fetus because of the use of x-ray
fluoroscopy during the treatment.
The major categories of medications used in stroke
prophylaxis are anticoagulants and antiplatelet agents. Their safety
profiles during pregnancy vary as follows:
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Aspirin – Category D (but a low dose is relatively safe)
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Dipyridamole – Category B (but the aspirin-dipyridamole combination is category D)
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Heparin and heparinlike compounds – Category C
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Heparin is routinely used during pregnancy when
anticoagulation is needed because it does not cross the placenta. It
takes effect quickly and can be stopped abruptly. Associated risks and
adverse reactions include heparin-induced thrombocytopenia, osteoporosis
(with the use of low-molecular-weight heparin or unfractionated
heparin), and bleeding.
Warfarin crosses the placenta and can cause complications
with organogenesis (ie, during weeks 6-12 of gestation). Maternal-fetal
bleeding can occur with warfarin, as can spontaneous abortions and
stillbirths.
Aspirin can result in fetal complications if given for
prolonged periods in high doses; therefore, it is not used for long-term
treatment with an antithrombotic agent in pregnancy. Adverse events
appear to be dose-related; hence, studies have used a low dose (60 mg),
which was not strongly associated with pregnancy-related complications.
Use of clopidogrel in human pregnancies has not been
adequately studied. Dipyridamole is also a category B drug in pregnancy.
Dipyridamole has not caused clinically significant teratogenic effects
in animals when given in moderate doses; further studies of its safety
must be performed. The aspirin-dipyridamole combination has limited use
in pregnancy because of the adverse effects of aspirin.
Hemorrhagic stroke
Management of hemorrhagic stroke depends on its location and
etiology. General measures include discontinuance of antithrombotics or
anticoagulation, management of blood pressure, and general supportive
measures. Ruptured cerebral aneurysms or AVMs that have bled may have to
be treated urgently either with open surgery or with endovascular
interventions.
It is easiest to proceed with these treatment decisions if
all parties agree that the life of the mother takes precedence. When
treatment is optimized for the mother, it may be impossible to safeguard
the fetus from all risks.
Prevention of stroke
All women may decrease their risk of stroke by avoiding
smoking, by maintaining a healthy body mass index, by avoiding excess
alcohol use, by avoiding use of all illegal drugs, and by having their
blood pressure checked periodically to detect hypertension. If they are
at particular risk for diabetes or elevated cholesterol levels, periodic
checks by their primary healthcare provider may be indicated. If
hypertension, diabetes, or hypercholesterolemia is diagnosed, meticulous
treatment lowers the risk of stroke.
Women with known cerebrovascular disease who are pregnant or
plan to become pregnant may take steps to maximize the safety of their
pregnancy. If they have previously experienced a cerebral infarction,
its cause should have been or should be determined, preferably before
the pregnancy occurs, so that appropriate measures can be instituted to
minimize the risk of recurrence.
In patients with a known cerebral aneurysm, clipping or
coiling should be performed, if possible. Consider cesarean delivery. In
patients with a known AVM, the lesion should be resected or embolized.
The preferred mode of delivery has not been established.
Opinions differ regarding the best approach to treating
pregnant women with hypercoagulable states (thrombophilia). Some authors
reserve anticoagulant treatment for those with severe thrombophilias by
considering the specific etiology and past clinical symptoms,
particularly those noted during previous pregnancies. Patients who
previously took warfarin because of recurrent venous thrombotic events
must be switched to heparin or a heparinoid before conceiving; this
anticoagulant regimen should be maintained throughout the pregnancy.
Some authorities add low-dose aspirin to manage relatively
severe thrombophilias. Decisions regarding treatment of mild or moderate
thrombophilias must be individualized; some authors reserve the use of
anticoagulation for the peripartum period.