Who is at risk for prolonged and postterm pregnancy?

Department of Obstetrics and Gynecology, University of California, San Francisco, CA, USA.
American journal of obstetrics and gynecology (Impact Factor: 3.97). 05/2009; 200(6):683.e1-5. DOI: 10.1016/j.ajog.2009.02.034
Source: PubMed

ABSTRACT The objective of the study was to examine risk factors for postterm (gestational age >or= 42 weeks) or prolonged (gestational age >or= 41 weeks) pregnancy.
We conducted a retrospective cohort study of all term, singleton pregnancies delivered at a mature, managed care organization. The primary outcome measures were the rates of pregnancies greater than 41 or 42 weeks' gestation. Multivariable logistic regression models were used to control for potential confounding and interaction.
Specific risk factors for pregnancy beyond 41 weeks of gestation include obesity (adjusted odds ratio [aOR], 1.26; 95% confidence interval [CI], 1.16-1.37), nulliparity (aOR, 1.46; 95% CI 1.42-1.51), and maternal age 30-39 years (aOR, 1.06; 95% CI, 1.02-1.10) and 40 years or older (aOR, 1.07; 95% CI, 1.02-1.12). Additionally, African American, Latina, and Asian race/ethnicity were all associated with a lower risk of reaching 41 or 42 weeks of gestation.
Our findings suggest that there may be biological differences that underlie the risk for women to progress to 41 or 42 weeks of gestation. In particular, obesity is a modifiable risk factor and could potentially be prevented with prepregnancy or interpregnancy interventions.

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    • "Obese women tend to have a longer gestation and are more likely to deliver beyond 41 weeks of pregnancy, especially when BMI reaches 35 kg/m 2 or more (Usha Kiran et al., 2005; Graves et al., 2006; Bhattacharya et al., 2007; Stotland et al., 2007; Denison et al., 2008; Caughey et al., 2009; Nohr et al., 2009). "
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    ABSTRACT: BACKGROUND: the incidence of obesity increases in all developed countries to frightful percentages, also in women of reproductive age. Maternal obesity is associated with important obstetrical complications; and this group also exhibits a higher incidence of prolonged pregnancies and labours. OBJECTIVE: to review the literature on the pathophysiology of onset and progression of labour in obese woman and translate this knowledge into practical recommendations for clinical management. METHODS: a literature review, in particular a critical summary of research, in order to determine associations, gaps or inconsistencies in this specific but limited body of research. FINDINGS: the combination of a higher incidence of post-term childbirths and increased inadequate contraction pattern during the first stage of labour suggests an influence of obesity on myometrial activity. A pathophysiologic pathway for altered onset and progression of labour in obese pregnant women is proposed. CONCLUSIONS: analysis of the literature shows that obesity is associated with an increased duration of pregnancy and prolonged duration of first stage of labour. IMPLICATIONS FOR PRACTICE: an adapted clinical approach is suggested in these patients.
    Midwifery 02/2013; 29(12). DOI:10.1016/j.midw.2012.12.013 · 1.71 Impact Factor
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    • "Th e most common maternal complication in PTP is maternal anxiety, dysfunctional labour, shoulder dystocia, obstetric trauma, induction of labour, caesarean delivery and postpartum haemorrhage (Briscoe et al. 2005). Neonatal complications include: low Apgar scores; acidaemia; macrosomia; admission to the neonatal intensive care unit (Caughey et al. 2009); meconium aspiration syndrome; clavicular fracture; Erb ' s palsy; and cerebral palsy (Moster et al. 2010). Besides those complications, researchers have found lag impact on the development of post-term infants in the follow-up studies (Field et al. 1977; Yang et al. 2010). "
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    ABSTRACT: The aim of this study was to examine the association between haemoglobin (Hb) concentration during pregnancy and the risk of post-term pregnancy (PTP). Based on data from a population-based prenatal care programme in South China, a total of 102,484 women who delivered during 1995-2000 were identified. Haemoglobin concentration was determined by using standard methods. Risk of PTP was analysed according to severity of anaemia and multiple Hb categories. Multivariable logistic regression models were used to control potential confounding factors. Results showed that the overall prevalence rate of PTP in the population was 4.8% (4,947/102,484). The rate was 5.0%, 4.7% and 4.8% for women who were anaemic, while it was 4.5%, 4.4% and 4.2% for women who were non-anaemic in the 1st, 2nd and 3rd trimester, respectively. Although anaemia in either of the trimesters was not significantly associated with an increased risk of PTP, the risk was two-fold higher (odds ratio, 2.06; 95% CI, 1.18-3.59) for women whose last trimester haemoglobin concentration was lower than 80 g/l, when compared with women whose last trimester haemoglobin concentration was 140 g/l or higher. Our findings suggest that a very low 3rd trimester haemoglobin level is associated with an increased risk of PTP.
    Journal of Obstetrics and Gynaecology 01/2013; 33(1):46-9. DOI:10.3109/01443615.2012.729108 · 0.60 Impact Factor
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