Fish are an excellent source of protein, are low in saturated fats, and contain omega-3 fatty acids. The Avon Longitudinal Study of Parents and Children reported beneicial efects on pregnancy outcomes in women who consumed 340 g or more of seafood weekly (Hibbeln, 2007). Because nearly all fish and shellish contain trace amounts of mercury, pregnant and lactating women are advised to avoid specific types of ish with potentially high methylmercury levels. These include shark, swordfish, king mackerel, and tile fish. It is further recommended that pregnant women ingest 8 to 12 ounces of fish weely, but no more than 6 ounces of albacore or "white" tuna (U.S. Environmental Protection Agency, 2014). If the mercury content oflocally caught fish is unknown, then overall fish consumption should be limited to 6 ounces per week (American Academy of Pediatrics and the American College of Obstetricians and Gynecologists, 2017) .
Maternal lead exposure has been associated with several adverse maternal and fetal outcomes across a range of maternal blood lead levels (Taylor, 2015). These include gestational hypertension, miscarriage, low birthweight, and neurodevelopmental impairments in exposed pregnancies (American College of Obstetricians and Gynecologists, 2016c). The levels at which these risks rise remains unclear. However, recognizing that such exposure remains a significant health issue for reproductive-aged women, the CDC (201 Oa) has issued guidance for screening and managing exposed pregnant and lactating women. These guidelines, which have been endorsed by the American College of Obstetricians and Gynecologists (2016c), recommend blood lead testing only if a risk factor is identified. If the levels are > 5 /Lg1 dL, then counseling is completed, and the lead source is sought and removed. Subsequent blood levels are obtained. Blood lead levels >45 Lg/dL are consistent with lead poisoning, and women in this group may be candidates for chelation therapy. Afected pregnancies are best managed in consultation with lead poisoning treatment experts. National and state resources are available at the CDC website: ww.cdc.gov/ncehllead/.
Pregnant women are encouraged to wear properly positioned three-point restraints as protection against automobile crash injury (Chap. 47, p. 927). The lap portion of the restraining belt is placed under the abdomen and across her upper thighs. The belt should be comfortably snug. The shoulder belt also is irmly positioned between the breasts. Airbags should not be disabled for the pregnant woman.
In general, air travel in a properly pressurized aircraft has no harmful efect on pregnancy (Aerospace Medical Association, 2003). Thus, in the absence of obstetrical or medical complications, the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists (20 16a, 2017) have concluded that pregnant women can safely ly up to 36 weeks' gestation. It is recommended that pregnant women observe the same precautions for air travel as the general population. Seatbelts are used while seated. Periodic lower extremity movement and at least hourly ambulation help lower the venous thromboembolism threat. Signiicant risks with travel, especially international travel, are infectious disease acquisition and development of complications remote from adequate healthcare resources (Ryan, 2002).