Preconceptional counseling includes assessment of immunity against common pathogens. Also, depending on health status, travel plans, and time of year, other immunizations may be indicated as discussed in Chapter 9 (Table 9-7, p. 172). Vac cines that contain toxoids such as tetanus are suitable before or during gestation. Also, those containing killed bacteria or viruses-such as inluenza, pneumococcus, hepatitis B, menin gococcus, and rabies vaccines-are not associated with adverse fetal outcomes and are not contraindicated preconceptionally or during pregnancy. Conversely, live-virus vaccines are not recommended during pregnancy. Examples are vaccines against varicella-zoster, measles, mumps, rubella, polio, chickenpox, and yellow fever. Moreover, 1 month or longer should ideally pass between vaccination and conception attempts. That said, inadvertent administration of measles, mumps, rubella (MMR) considered indications for pregnancy termination. Most reports indicate that the fetal risk is only theoretical. Immunization to smallpox, anthrax, and other bioterrorism diseases should be discussed if clinically appropriate (Chap. 64, p. 1228).
With some infections, vaccines are unavailable. One recent example is the Zika virus (Brasil, 2016). For this virus, the CDC has issued travel advisories for pregnant women (Petersen, 2016; Schuler-Faccini, 2016).
he CDC (20e16) estimates that 3 percent of neonates born each year in the United States will have at least one birth defect. Importantly, such defects are the leading cause of infant mortality and account for 20 percent of deaths. The benefits of preconceptional counseling usually are measured by comparing the incidence of new cases before and after initiation of a counseling program. Congenital conditions that clearly beneit from patient education include neural-tube defects, phenylketonuria, thalassemias, and other genetic diseases more common in individuals of Eastern European Jewish descent.
Pedigree construction using the symbols shown in Figure 8-2 is the most thorough method for obtaining a family history as a part of genetic screening. he health and reproductive status of each "blood relative" should be individually reviewed for medical illnesses, mental retardation, birth defects, infertility, and pregnancy loss. Certain racial, ethnic, or religious backgrounds may indicate elevated risk for specific recessive disorders.
Although most women can provide some information regarding their history, their understanding may be limited. For example, several studies have shown that pregnant women often fail to report a birth defect in the family or they report it incorrectly. hus, any disclosed defect or genetic disease should be conirmed by reviewing pertinent medical records or by contacting afected relatives for additional information.