Browsing by Subject "Gestational age"

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    A centile chart for birth weight for an urban population of the Western Cape
    (1995) Theron, G B; Thompson, M L
    Evidence from large epidemiological studies has supported concern that being born light for gestational age (LiGA) may be detrimental. The incidence of LiGA babies is an important indicator of the health of women of reproductive age in deprived communities. In the assessment of LiGA in the Western Cape, centile charts constructed for populations in other parts of the world are generally used. These charts, however, may not be appropriate. Patients residing in the area served by the Tygerberg Hospital obstetric service, who booked early with singleton pregnancies, had their gestational age confirmed by early ultrasound and delivered between 1 March 1989 and 28 February 1990 were included in the study. The sample consisted of 3 643 patients. The mean birth weight was 2 995 g (SD 573 g) and the range 760 - 5 080 g. The distribution of birth weight at each week of gestation from 28 to 42 weeks was not normal. The 4-parameter Johnson family of densities was used to model the distribution of birth weight at each gestational age. A comparison of the distribution of birth weight in the study relative to the perinatal growth chart for international reference constructed by Dunn was also made. In addition to considering an overall chart, the sample was subdivided according to a number of characteristics (e.g. gender, firstborn and latter-born babies, smoking habit, hypertensive disorders and induction of labour) in order to explore their impact on the distribution of birth weight. Having explored the potential impact of all these factors, it was concluded that a single chart including all patients could be constructed.
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    Open Access
    The association between timing of initiation of antenatal care and stillbirths: a retrospective cohort study of pregnant women in Cape Town, South Africa
    (BioMed Central, 2014-06-13) Beauclair, Roxanne; Petro, Greg; Myer, Landon
    Background: There is renewed interest in stillbirth prevention for lower-middle income countries. Early initiation of and properly timed antenatal care (ANC) is thought to reduce the risk of many adverse birth outcomes. To this end we examined if timing of the first ANC visit influences the risk of stillbirth. Methods: We conducted an analysis of a retrospective cohort of women (n = 34,671) with singleton births in a public perinatal service in Cape Town, South Africa. The main exposure was the gestational age at the first ANC visit. Bivariable analyses examining maternal characteristics by stillbirth status and gestational age at the first ANC visit, were conducted. Logistic regression, adjusting for maternal characteristics, was conducted to determine the risk of stillbirth. Results: Of the 34,671 women who initiated ANC, 27,713 women (80%) were retained until delivery. The population stillbirth rate was 4.3 per 1000 births. The adjusted models indicated there was no effect of gestational age at first ANC visit on stillbirth outcomes when analyzed as a continuous variable (aOR 1.01; 95% CI: 0.99-1.04) or in trimesters (2nd Trimester aOR 0.78, 95% CI: 0.39-1.59; 3rd Trimester OR 1.03, 95% CI: 0.50-2.13, both with 1st Trimester as reference category). The findings were unchanged in sensitivity analyses of unobserved outcomes in non-retained women. Conclusion: The timing of a woman’s first ANC visit may not be an important determinant of stillbirths in isolation. Further research is required to examine how quality of care, incorporating established, effective biomedical interventions, influences outcomes in this setting.