Developmental stages 3 stages 1. Preembryonic stage-stage of ovum 3wk after fertilization: tissue grow and differentiate 2. ****Embryonic stage- 4- 8wks:organogenesis**** 3. Fetal stage- growth and further development of organ and system
Role of nurse Assess clients for environmental and behavioral risks. Design individualized plans of care that support women in reducing risks in their lifestyles.
Role of nurse Intervene using teaching, support, observations, and referrals to minimize environmental risks in pregnancy.
Role of nurse Provide ongoing evaluation of maternal and fetal well-being so that care can be tailored to each client’s changing needs.
Ionizing radiation Energy in wave or particle form,such as X-rays. The fetal CNS is vulnerable to high-dose radiation, particularly between 7 and 15 weeks gestation. 1920- microcephaly and CNS disturbance. 1945- Hiroshima and Nagasaki(atomic bombs) also.
1980- nuclear power plant accident in Chernobyl,(radioactive cesium) – NTD and other malformations, spontaneous abortions and fetal growth retardation.
Pesticides and herbicides increase the risks of spontaneous abortion and fetal death and malformation such as cleft lip or extra fingers ( Needleman & Bellinger,1994 ).
Industrial Contaminant Heavy metals 1. Mercury – 1 ppm ;safe 2. Lead- cause reproductive problems (miscarriage, fetal demise, preterm, growth delay and IQ decrease ) 3. Arsenic -cardiac defects
PCBs PBBs Polychlorinated biphenyls (PCBs) Polybromated biphynyls (PBBs) Used in coolants,sealants flame retardants. 1985- PCB-contaminated cooking oil in Japan ; infant ;dark-pigmented skin,gum hyperplasia and LBW.
Solvents FOUND IN DRY-CLEANING PRODUCTS, SPRAY ADHESIVES, PAINTS, NAIL POLISH REMOVERS, FELT-TIPPED PEN ETC. Toluene – cardiovascular malformations, miscarriage and anencephaly.
Carbon Monoxide Carbon Monoxide is a colorless,odorless and extremely toxic gas. In animal model – fetal death, neurologic abnormalities, and LBW.
Heat and Radiation Radiation Less than 0.05 Gy –safe. Complete avoidance of X-ray exposure during the first 15 weeks is recommended. More than 0.2 Gy-birth defects. Pregnancy should be limited to no more than 0.005 Gy( Office of technology Assessment,1985 ).
Fatigue and Physical Risks Jobs : stand for long period,lift heavy objects,climb stair, sitting for 8-hour workday fatigue preterm birth,low birth weight,(Simpson,1993). : standing at work more than 7 hours a day increased spontaneous abortion(Fenster et al., 1997).
Food Additives and Contaminants FDA Artificial additive Caffeine Smoking Food contaminant
Vitamins Calcium Iron Folic acid Vit A not more than 18,000 IU/d
Teratogenic Risks of Drugs FDA Categories AControlled studies in women fail to demonstrate a risk to the fetus in the first trimester or later trimesters. Possibility of fetal harm appears remote
Teratogenic Risks of Drugs FDA Categories BAnimal reproduction studies have not demonstrateed a fetal risk, but there are no controlled studies in pregnant women. Or animal studies have shown an adverse effect but the risk is not confiemed in human studies in the first trimester ( there is no evidence of risk in later trimesters).
Teratogenic Risks of Drugs FDA Categories CStudies in animals have revealed adverse effects on the fetus, and there are no controlled studies in pregnant women. Or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potentil risk to the fetus.
Teratogenic Risks of Drugs FDA Categories DXDX There is positive evidence of human fetal risk, but the benefits from use may be acceptable despite the risk. Studies in animals or humans have demonstrated fetal abnormalities.