The United States Surgeon General’s Family History Initiative was launched to educate healthcare providers and patients about the value of using family history as a screening tool for inherited medical conditions and single-gene disorders.6 A family history is indicated for both partners7 and positive responses are followed up by risk assessment, testing, and genetic counseling. Completing genetic counseling and testing before conception is beneficial.8
Maternal genetic conditions
Precise identification of maternal genetic conditions is important when reviewing maternal risks and offspring morbidities associated with pregnancy, counseling about mode of inheritance, partner carrier screening, and risk of genetic condition in the offspring, and determining which prenatal diagnostic or preimplantation genetic screening or testing to recommend (Table 3).
Infections and immunizations
Immunization outside of pregnancy is generally preferable and live-virus vaccines are contraindicated in pregnancy because of their theoretical risk to the fetus.
Two vaccinations, however, are of particular importance antepartum: influenza and pertussis. Influenza can cause significant morbidity and mortality in pregnancy and all clinicians who care for women of reproductive age should encourage them to be vaccinated for influenza every year.9 Women planning pregnancy should also receive tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccines during each pregnancy, between 27 and 36 weeks’ gestation.10
Increased understanding of the link between Zika virus and fetal neurological effects adds another discussion to preconception counseling. Because the rate of vertical transmission is unknown, the CDC recommends that women who have been diagnosed with Zika and those who may have been exposed wait at least 8 weeks after their exposure or onset of symptoms before attempting conception. The CDC website should be reviewed for the most up-to-date recommendations because they change regularly. Male partners should wait at least 6 months after their symptoms resolve to have unprotected intercourse.11 Women who reside in endemic areas should discuss reproductive life planning with a physician knowledgeable about Zika. The current recommendation is that they delay pregnancy.12
Chronic medical conditions
Physicians should ascertain chronic medical conditions as a part of preconception care. Some common medical conditions that have an effect on or are affected by pregnancy are briefly discussed below. All preexisting chronic medical conditions should be optimized preconceptionally with a multidisciplinary team.
Seizure disorders: Seizure disorders are the most common neurologic diseases in pregnancy. One-third of women with a seizure disorder will experience more frequent seizures while pregnant. Seizure disorders increase the risk of congenital anomalies, whether or not the woman is taking antiepileptic drugs (AEDs).13 Women should be managed on the most effective AED, ideally monotherapy at the lowest effective dose, with the exception of valproate, which should be avoided. Given the increased rate of NTDs associated with AEDs, supplementation with 4 mg of folic acid (versus 0.4 mg) should be initiated before conception.
Hypertension: Chronic hypertension (cHTN) affects 3% to 5% of women of reproductive age.14 cHTN in pregnancy is associated with higher rates of preterm birth, placental abruption, intrauterine growth restriction, preeclampsia, and fetal demise. Women with cHTN are at risk of worsening hypertension and end organ damage, and 20%–25% develop superimposed preeclampsia.15 Treating severe-range blood pressures improves pregnancy outcomes.16 Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are considered Category C in the first trimester and Category D in the second and third trimesters, and should be discontinued before conception. Labetalol, nifedipine, and methyldopa are the optimal agents to use during pregnancy; however, other agents can also be used with caution and in coordination with a maternal-fetal medicine (MFM) specialist.15 Women with long-standing hypertension should be assessed for retinopathy, renal disease, and ventricular hypertrophy.
Congenital cardiac disease: As more women with congenital cardiac disease, both corrected and uncorrected, reach reproductive age, preconception counseling for them becomes increasingly important. Pregnancy and its associated changes in cardiovascular physiology can pose significant risks. These women require a multidisciplinary approach with cardiology and MFM. The New York Heart Association Functional Classifications and World Health Organization Classification of Maternal Risk should be used.17