Medline ® Abstracts for References 124,125,128
of 'Treatment and outcome of nausea and vomiting of pregnancy'
Hyperemesis gravidarum. Effects on fetal outcome.
Hallak M, Tsalamandris K, Dombrowski MP, Isada NB, Pryde PG, Evans MI
J Reprod Med. 1996;41(11):871.
OBJECTIVE: To study perinatal outcomes in pregnancies complicated by hyperemesis gravidarum (HG) as compared to controls.
STUDY DESIGN: Between 1984 and 1991, 138 patients were diagnosed with HG according to Fairweather's criteria. Subjects were stratified into groups of mild and severe HG according to the presence of at least one of the following criteria: ketonuria, increased blood urea nitrogen and hematocrit, and/or abnormal electrolytes. All patients without HG on whom records were available and who delivered during the study period were included as controls. Multiple gestations and stillbirths were excluded from the analysis. Student's t test and X2 were used for statistical analysis.
RESULTS: Demographic data were not significantly different between the groups. Forty patients were diagnosed as having mild HG and 98 patients as having severe; 12,335 patients were defined as controls. Mean fetal birth weights were 3,110, 3,093, and 3,160 g in the mild, severe and control groups, respectively. The incidence of congenital anomalies was 2.5%, 2.0% and 1.6%, respectively. The incidence of prematurity was 17.5%, 11.2% and 10.7% in mild and severe HG and controls, respectively. None of the outcome variables for mild or severe HG were significantly different as compared to the controls. Differences in other neonatal outcomes, including frequency of five-minute Apgar score<7 and neonatal intensive care unit admissions, were not significantly different between the three groups.
CONCLUSION: In contrast to previous reports, this study demonstrated that fetuses of gravidas admitted for HG are not at increased risk of growth retardation, congenital anomalies or prematurity. No beneficial effect on pregnancy outcome was detected.
Department of Obstetrics and Gynecology, Wayne State University, School of Medicine, Detroit, Michigan, USA.
Maternal and fetal outcomes in hyperemesis gravidarum.
Tsang IS, Katz VL, Wells SD
Int J Gynaecol Obstet. 1996;55(3):231.
OBJECTIVE: This study sought to evaluate maternal characteristics and pregnancy outcomes among women with hyperemesis gravidarum.
METHODS: We performed a retrospective analysis of pregnancy records of obstetric admissions during a 6-year period. Women treated as out-patients for hyperemesis were also identified. Hyperemesis was defined as excessive nausea and vomiting resulting in dehydration, extensive medical therapy, and/or hospital admission. Statistical analysis was by t-test and chi square.
RESULTS: We identified 193 women (1.5%) who developed hyperemesis among 13,053 women. Racial status, marital status, age, and gravidity were similar between the hyperemesis patients and the general population. However, there were less women with hyperemesis who were para 3 or greater. Forty-six women (24%) required hospitalization for hyperemesis, mean hospital stay 1.8 days, range 1-10 days. One patient required parenteral nutrition, two had yeast esophagitis, none had HIV infection, psychiatric pathology or thyroid disease. Pregnancy outcomes between hyperemesis patients and the general population were similar for mean birth weight, mean gestational age, deliveries less than 37 weeks, Apgar scores, perinatal mortality or incidence of fetal anomalies. Our incidence of hyperemesis (1.5%) is similar to that of other published reports.
CONCLUSION: Women with hyperemesis have similar demographic characteristics to the general obstetric population, and have similar obstetric outcomes.
Department of OB/GYN, UNC School of Medicine, Eugene, OR, USA.
Morning sickness: a mechanism for protecting mother and embryo.
Flaxman SM, Sherman PW
Q Rev Biol. 2000;75(2):113.
Approximately two-thirds of women experience nausea or vomiting during the first trimester of pregnancy. These symptoms are commonly known as morning sickness. Hook (1976) and Profet (1988) hypothesized that morning sickness protects the embryo by causing pregnant women to physically expel and subsequently avoid foods that contain teratogenic and abortifacient chemicals, especially toxic chemicals in strong-tasting vegetables, caffeinated beverages and alcohol. We examined this hypothesis by comprehensively reviewing the relevant medical, psychological and anthropological literature. In its support, (i) symptoms peak when embryonic organogenesis is most susceptible to chemical disruption (weeks 6-18), (ii) women who experience morning sickness are significantly less likely to miscarry than women who do not (9 of 9 studies), (iii) women who vomit suffer fewer miscarriages than those who experience nausea alone, and (iv) many pregnant women have aversions to alcoholic and nonalcoholic (mostly caffeinated) beverages and strong-tasting vegetables, especially during the first trimester. Surprisingly, however, the greatest aversions are to meats, fish, poultry, and eggs. A cross-cultural analysis using the Human Relations Area Files revealed 20 traditional societies in which morning sickness has been observed and seven in which it has never been observed. The latter were significantly less likely to have animal products as dietary staples and significantly more likely to have only plants (primarily corn) as staples than the 20 societies in which morning sickness occurred. Animal products may be dangerous to pregnant women and their embryos because they often contain parasites and pathogens, especially when stored at room temperatures in warm climates. Avoiding foodborne microorganisms is particularly important to pregnant women because they are immunosuppressed, presumably to reduce the chances of rejecting tissues of their own offspring (Haig 1993). As a result, pregnant women are more vulnerable to serious, often deadly infections. We hypothesize that morning sickness causes women to avoid foods that might be dangerous to themselves or their embryos, especially foods that, prior to widespread refrigeration, were likely to be heavily laden with microorganisms and their toxins. The alternative hypotheses that morning sickness is (i) an epiphenomenon of mother-offspring genetic conflict or hormones associated with viable pregnancies, or (ii) an indicator to potential sexual partners and kin that the woman is pregnant, resulting in reduced sexual behavior and increased nepotistic aid, were not well supported. Available data are most consistent with the hypothesis that morning sickness serves an adaptive, prophylactic function.
Department of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853, USA. firstname.lastname@example.org