A 27-year-old nulligravid woman comes to the office for a routine visit. Medical history is significant for epilepsy that is well controlled with valproate and chronic hypertension for which she takes nifedipine. She hopes to conceive in the next few months and plans to start prenatal vitamins soon. The patient takes no other medications and does not use tobacco, alcohol, or illicit drugs. Blood pressure is 120/80 mm Hg. Physical examination is normal. If the patient conceives now, her fetus is at increased risk for which of the following anomalies?

Question

A 27-year-old nulligravid woman comes to the office for a routine visit.  Medical history is significant for epilepsy that is well controlled with valproate and chronic hypertension for which she takes nifedipine.  She hopes to conceive in the next few months and plans to start prenatal vitamins soon.  The patient takes no other medications and does not use tobacco, alcohol, or illicit drugs.  Blood pressure is 120/80 mm Hg.  Physical examination is normal.  If the patient conceives now, her fetus is at increased risk for which of the following anomalies?

Quizplus · Accepted Answer

11ec160b_3c49_234e_9249_7db6593c1a73_MD0001_00 Preconception counseling is recommended in reproductive-age women with chronic medical conditions and desire for pregnancy to optimize the patient's health and identify risk factors for potential obstetric complications. This patient with epilepsy controlled with valproate is at increased risk for fetal neural tube defects. Valproate, an antiepileptic agent also used to prevent migraine headache and treat bipolar disorder, is contraindicated in pregnancy because it interferes with folate metabolism and causes maternal folate deficiency. Folic acid is required to regulate fetal neural tube closure in early pregnancy; therefore, patients taking valproate are at increased risk for incomplete neural tube closure (eg, meningocele, myelomeningocele) compared to the general population. Because most women discover that they are pregnant after the most vulnerable period of neural tube formation (eg, 4 weeks gestation), patients on valproate should try to optimize seizure control prior to conception with an alternate anticonvulsant (eg, levetiracetam). Low-dose folic acid supplementation is recommended in all women before conception; high-dose folic acid supplementation is recommended in the presence of risk factors such as current valproate use or a prior child with a neural tube defect. (Choices A and E) Epiphyseal stippling (pinpoint calcification) and nasal hypoplasia (depression of the nasal bridge) are characteristics of warfarin embryopathy caused by first-trimester exposure to warfarin. (Choices B and G) Maternal hypothyroidism, neonatal hypothyroidism, and fetal tricuspid valve malformation (ie, Ebstein anomaly) are associated with lithium use during pregnancy. Neonatal hypothyroidism can also result from exposure to maternal antithyroid medications (eg, propylthiouracil, methimazole). (Choice C) Micrognathia, or hypoplasia of the mandible, is a craniofacial malformation that can occur with fetal exposure to isotretinoin. It is also commonly associated with genetic syndromes (eg, Trisomy 18). (Choice F) Renal dysgenesis and fetal anuria/oligohydramnios can result from the use of ACE inhibitors and angiotensin receptor blockers during pregnancy. These medications are contraindicated in pregnancy, but other antihypertensive medications such as nifedipine and labetalol are safe because they have no teratogenic effects. Educational objective: Valproate is a teratogenic medication that decreases maternal folate levels and increases the risk of fetal neural tube defects (eg, meningocele, myelomeningocele). __________ References: Valproic acid monotherapy in pregnancy and major congenital malformations. (http://www.ncbi.nlm.nih.gov/pubmed/20558369)

A 27-Year-Old Nulligravid Woman Comes to the Office for a Routine