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Nonindigenous Women (nonindigenou + woman)
Selected AbstractsVillous trophoblast growth in pregnancy at high altitudeJOURNAL OF ANATOMY, Issue 5 2002T. M. Mayhew The trophoblastic epithelium of placental villi exhibits continuous turnover. Phases of proliferation, recruitment, maturation, terminal differentiation (apoptosis) and extrusion exist in steady state and occur in distinctive spatial compartments, viz. cytotrophoblast cells (CT), syncytiotrophoblast (ST), syncytial knots (SK), denudation sites (DEN) and syncytial fragments. Hypoxia in vitro stimulates CT proliferation but inhibits recruitment into ST. Pregnancy at high altitude (HA) is associated with reduced birthweight and provides a convenient model of preplacental (hypobaric) hypoxia. HA placentas show impoverished villous growth and changes in the incidences of CT cells and SK regions. Here we examine placentas from Amerindian and nonindigenous women who completed full-term pregnancies at low altitude (LA; 400 m; n = 25) and high altitude (HA; 3600 m; n = 45) in Bolivia. We test the hypothesis that HA pregnancy disturbs the epithelial steady state as reflected in the relative volumes and surfaces of trophoblast compartments. Masson trichrome stained tissue sections and microscopical fields were generated by uniform random sampling. Point and intersection counts were used to estimate the volumes and surface areas of nonsyncytial knots (nonSK), SK regions, syncytial bridges (SB) and denudation sites (DEN). Absolute values were compared by 2-way analyses of variance to resolve altitudinal from ethnic effects. At LA, trophoblast comprised about 85% nonSK, 8% SK, 5% SB and 3% CT by volume. Its maternal surface area comprised about 91% nonSK, 5% SK, 2% SB, and 3% DEN. Apart from CT (the fractional volume of which increased to 4%, P < 0.05), relative volumes of trophoblast compartments did not alter significantly at HA. However, there was a roughly 30% reduction in absolute volume of trophoblast at HA (P < 0.001) which could be explained mainly by a decrease in volume of nonSK regions (P < 0.001). The volume of CT was unaltered. Absolute surface areas of villi also declined at HA (by 20%, P < 0.01) and, again, this was attributed mainly to nonSK. The findings confirm that poor villous growth is partly due to failure of trophoblast to attain the growth seen at LA. The reduced trophoblastic growth occurs despite an increase in relative volume of CT cells (consistent with previously reported increases in proliferative activity) and, probably, by a combination of compromised syncytial fusion and continuing extrusion of syncytial fragments. [source] The amounts and deposition patterns of fibrin-type fibrinoid at the villous surface are altered in pregnancy at high altitudeJOURNAL OF ANATOMY, Issue 5 2002T. M. Mayhew In pregnancy at high altitude, there is preplacental (hypobaric) hypoxia and intrauterine fetal growth is restricted. Previous studies on placentas from Amerindian and nonindigenous women completing term pregnancies at low (LA; 400 m) and high (HA; 3600 m) altitudes in Bolivia showed that HA placentas had smaller surface areas of villi and smaller volumes of fibrin type fibrinoid (FTF). Recently we devised a stereological method for testing whether perivillous FTF (pFTF) is randomly distributed at the surface of villous trophoblast. Here the method is applied to test 2 experimental hypotheses: [1] deposition of pFTF is nonrandom regardless of altitude and [2] deposition patterns differ between altitudes. Uniform random samples of microscopical fields were drawn from Masson trichrome stained sections and intersection counts used to estimate the surface areas of, and patterns of pFTF on, 4 regions of trophoblast: nonsyncytial knots (nonSK), syncytial knots (SK), syncytial bridges (SB) and denudation sites (DEN). Absolute areas were compared by 2-way analyses of variance. Expected and observed distributions were compared by (2 and contingency table analyses. At LA the mean (SEM) volume of FTF was 8.4 (1.54) cm3 and villous surface area was 7.0 (0.43) m2. At HA FTF volume was reduced by about 50% (P < 0.01) and villous surface by 20% (P < 0.01). The surface composition of trophoblast in LA placentas was nonSK (91%), SK (5%) and SB and DEN (both less than 3%). Relative surfaces were not significantly altered in HA placentas but, due to the impoverished growth of villi at HA, the changes represented a real decline in absolute surface of nonSK. At HA, the total surface of pFTF on trophoblast decreased by about 40%, from 4430 (564) cm2,2570 (406) cm2 (P < 0.01). At both altitudes pFTF deposition was preferentially found at DEN (12-fold greater than expected for a random distribution). Pattern differences were detected between altitudes. In HA placentas the amount of pFTF deposited on nonSK regions was about 45% less (P < 0.05); apparent changes on SK and SB regions were not significant. These histometric findings suggest that the coagulation-fibrinolysis steady state is altered at HA and favours greater fibrinolysis. At least some of the fibrinolytic or anticoagulant activity seems to reside in or on thinner regions of villous trophoblast and the placenta may be a relatively privileged site in terms of fibrinolysis. Also, reduced deposition of pFTF is probably linked to changes in the steady state of trophoblast turnover which seems to be perturbed in HA pregnancies. [source] Secular trend in age at menarche in indigenous and nonindigenous women in ChileAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010X.M. Ossa Objectives: To estimate the secular trend in age at menarche, comparing indigenous and nonindigenous women, and its relationship with socio-demographic, family and nutritional factors. Methods: A study (historical cohorts) of 688 indigenous and nonindigenous women, divided into four birth cohorts (1960,69, 1970,79, 1980,89, and 1990,96) in an area in central southern Chile was carried out. Data and measurements were collected by health professionals using a previously validated questionnaire. Age at menarche was self-reported (recall). Adjusted differences among cohorts were estimated using a multivariate regression model. Results: A secular trend (P < 0.001) in age at menarche was found in both ethnic groups, with no significant differences between them (P > 0.05). In an adjusted model, a reduction in age at menarche was estimated at 3.7 months per decade between 1960 and 1990. This trend was moderated by higher socio-economic level, smaller number of siblings, and cohabitation with a single parent during infancy. Conclusions: The trend has occurred in a steady progression over time in indigenous women, whereas in nonindigenous women, it was slow initially but has accelerated in recent years. Nonindigenous women have maintained a slightly lower age of menarche than their indigenous counterparts. Am. J. Hum. Biol. 22:688-694, 2010. © 2010 Wiley-Liss, Inc. [source] Persistent high rates of hysterectomy in Western Australia: a population-based study of 83 000 procedures over 23 yearsBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 7 2006K Spilsbury Objective, To investigate incidence trends and demographic, social and health factors associated with the rate of hysterectomy and morbidity outcomes in Western Australia and compare these with international studies. Design, Population-based retrospective cohort study. Setting, All hospitals in Western Australia where hysterectomies were performed from 1981 to 2003. Population, All women aged 20 years or older who underwent a hysterectomy. Methods, Statistical analysis of record-linked administrative health data. Main outcome measures, Rates, rate ratios and odds ratios for incidence measures and length of stay in hospital and odds ratios for morbidity measures. Results, The age-standardised rate of hysterectomy adjusted for the underlying prevalence of hysterectomy decreased 23% from 6.6 per 1000 woman-years (95% CI 6.4,6.9) in 1981 to 4.8 per 1000 woman-years (95% CI 4.6,4.9) in 2003. Lifetime risk of hysterectomy was estimated as 35%. In 2003, 40% of hysterectomies were abdominal. The rate of hysterectomy to treat menstrual disorders fell from 4 per 1000 woman-years in 1981 to 1 per 1000 woman-years in 1993 and has since stabilised. Low socio-economic status, having only public health insurance, nonindigenous status and living in rural or remote areas were associated with increased risk of having a hysterectomy for menstrual disorders. Indigenous women had higher rates of hysterectomy to treat gynaecological cancers compared with nonindigenous women, particularly in rural areas. The odds of a serious complication were 20% lower for vaginal hysterectomies compared with abdominal procedures. Conclusion, Western Australia has one of the highest hysterectomy rates in the world, although proportionally, significantly fewer abdominal hysterectomies are performed than in most countries. [source] | ||||||||||