A seizure is deined as a paroxysmal disorder of the central nervous system characterized by an abnormal neuronal discharge with or without loss of consciousness. Some identiiable causes of convulsive disorders in young adults include head trauma, alcohol-and other drug-induced withdrawals, cerebral infections, brain tumors, biochemical abnormalities, and arteriovenous malformations. A search for these is prudent with a new-onset seizure disorder in a pregnant woman. he diagnosis of idiopathic epilepsy is one of exclusion.
Epilepsy encompasses diferent syndromes whose cardinal feature is a predisposition to recurrent unprovoked seizures. he International League Against Epilepsy Commission on Classiication and Terminology recently updated the following deinitions (Fisher, 2014).
These originate in one localized brain area and afect a correspondingly localized area of neurological unction. They are believed to result from trauma, abscess, tumor, or perinatal factors, although a speciic lesion is rarely demonstrated. Focal seizures without dyscognitive eatures start in one region of the body and progress toward other ipsilateral areas of the body, producing tonic and then clonic movements. Simple seizures can afect sensory unction or produce autonomic dysfunction or psychological changes. Cognitive function is not impaired, and recovery is rapid. Focal seizures with dyscognitive eatures are oten preceded by an aura and followed by impaired awareness manifested by sudden behavioral arrest or motionless stare. Involuntary movements such as picking motions or lip smacking are common.
These involve both brain hemispheres and may be preceded by an aura before an abrupt loss of consciousness. There is a strong hereditary component. In generalized tonic-clonic seizures, loss of consciousness is followed by tonic contraction of the muscles and rigid posturing, and then by clonic contractions of all extremities while the muscles gradually relax. Return to consciousness is gradual, and the patient may remain confused and disoriented for several hours. Absence seizures-also called petit mal seizures-are a form of generalized epilepsy that involve a brief loss of consciousness without muscle activity and are characterized by immediate recovery of consciousness and orientation.
Women with epilepsy ideally are counseled before pregnancy and relevant points are presented also in Chapter 8 (p. 148). Folic acid supplementation with 0.4 mg per day is begun at least 1 month before conception. The dose is increased to 4 mg when the woman taking antiepileptic medication becomes pregnant. hese medications are assessed and adjusted with a goal of mono therapy using the least teratogenic medication. If this is not feasible, then attempts are made to reduce the number of medications used and to use them at the lowest efective dose (Patel, 2016). Medication withdrawal should be considered if a woman is seizure free for 2 years or more.
The major pregnancy-related risks to women with epilepsy are fetal malformations and increased seizure rates. Seizure control is the main priority to avoid its attendant morbidity and mortality risks. Early studies described worsening seizure activity during pregnancy, however, this is less so now because of more efective drugs. Contemporary studies cite higher rates of seizure activity in only 20 to 30 percent of pregnant women (Mawer, 2010; Vajda, 2008). Women who are seizure free for at least 9 months before conception will likely remain so during pregnancy (Harden, 2009b).