MKSAP Quiz: Medication for a patient attempting conception

This month's quiz asks readers to evaluate a 32-year-old woman who is planning to attempt conception with her partner and has a history of systemic lupus erythematosus complicated by chronic kidney disease.

A 32-year-old woman is evaluated as a new patient. She is planning to attempt conception with her partner. She has a history of systemic lupus erythematosus complicated by chronic kidney disease that has been inactive for several years off of treatment. She has had borderline blood pressure elevations since the diagnosis of kidney disease. She was also diagnosed with impaired fasting glucose and mild hyperlipidemia 2 years ago, both of which have been treated with dietary changes. Her current medications are calcium and vitamin D supplements.

On physical examination, blood pressure is 156/92 mm Hg and her vital signs are otherwise normal. BMI is 26. The remainder of the physical examination, including a gynecologic examination, is normal.

Laboratory studies normal electrolytes, blood urea nitrogen 12 mg/dL (4.2 mmol/L), creatinine 1.2 mg/dL (106.0 µmol/L), total cholesterol 250 mg/dL (6.4 mmol/L), LDL cholesterol 160 mg/dL (4.1 mmol/L), HDL cholesterol 34 mg/dL (0.8 mmol/L), and triglycerides 200 mg/dL (2.26 mmol/L). Spot urine albumin/creatinine ratio is 300 mg/g and HbA1c is 7.5%.

In addition to a daily prenatal vitamin, which of the following is the most appropriate treatment?

A. Aspirin
B. Lisinopril
C. Metformin
D. Simvastatin

MKSAP Answer and Critique

The correct answer is C. Metformin. This item is available to MKSAP 16 subscribers as item 32 in the General Internal Medicine section. Information about MKSAP 16 is available online.

The most appropriate treatment for this woman is metformin to treat her type 2 diabetes mellitus. Each visit with a reproductive-age woman represents an opportunity for preconception counseling, as adequate preconception care can reduce the risks for preterm birth and birth anomalies, particularly in a woman actively contemplating pregnancy. If this patient were to become pregnant, her poorly controlled diabetes and hypertension increase her risk for adverse maternal and fetal outcomes. This patient should be counseled about her risk factors for potential medical complications of pregnancy, and she should be referred to a high-risk obstetrician for co-management of her medical and gynecologic issues should she become pregnant. It is essential to avoid prescribing teratogenic medications to reproductive-age women who may become pregnant. Metformin is an FDA pregnancy class B medication and is a reasonable option for controlling this patient's hyperglycemia before pregnancy. If she were to become pregnant, consideration may be given to discontinuing the metformin and starting insulin therapy, which is the preferred treatment of diabetes in pregnancy.

The risk of premature fetal loss is increased in women with systemic lupus erythematosus, particularly in those with the antiphospholipid antibody syndrome. Low-dose aspirin has been used in these patients to attempt to lower this risk, although the effectiveness of this intervention is not clear. As aspirin may interfere with implantation when used near the time of conception and this patient has no clear indication for aspirin therapy at present, it should not be prescribed.

Lisinopril and simvastatin, and all ACE inhibitors and statins, are teratogenic medications and can cause serious fetal anomalies. They are FDA pregnancy class X medications and should not be prescribed to this patient who is anticipating pregnancy. Additionally, although this patient might benefit from treatment with an angiotensin receptor blocker because of her diabetes and proteinuria, this class of medication is also contraindicated in pregnancy owing to its potential teratogenic effects. Labetalol or methyldopa is safely used for the treatment of hypertension in pregnant women, and may be considered for this patient. Bile acid resins, such as colestipol, are not orally absorbed and are FDA pregnancy class B medications. They may be a useful adjunct to diet and lifestyle therapy for managing this patient's dyslipidemia.

Key Point

  • Avoidance of potentially teratogenic medications is important when treating medical conditions in reproductive-age women contemplating pregnancy.