Severity and duration of nausea and vomiting symptoms in pregnancy and spontaneous abortion

Department of Maternal and Child Health, School of Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7435, USA.
Human Reproduction (Impact Factor: 4.57). 11/2010; 25(11):2907-12. DOI: 10.1093/humrep/deq260
Source: PubMed


Earlier studies have shown an inverse association between the presence of nausea and vomiting in pregnancy (NVP) and spontaneous abortion (SAB), but no study to date has examined the effects of symptom duration on the risk of SAB.
We examined NVP symptom severity and duration in relation to the occurrence of SAB. Data were collected from 2407 pregnant women in three US cities between 2000 and 2004 through interviews, ultrasound assessments and medical records abstractions. Discrete-time continuation ratio logistic survival models were used to examine the association between NVP and pregnancy loss.
Lack of NVP symptoms was associated with increased risk for SAB [adjusted odds ratio (OR) = 3.2, 95% confidence interval (CI): (2.4, 4.3)], compared with having any symptoms. Reduced risks for SAB were found across most maternal age groups for those with NVP for at least half of their pregnancy, but the effects were much stronger in the oldest maternal age group [OR = 0.2, 95% CI: (0.1, 0.8)].
The absence of NVP symptoms is associated with an increased risk of early pregnancy loss. As symptom duration decreases, the likelihood of early loss increases, especially among women in the oldest maternal age group.

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    • "One possibility is that pregnancy sickness is simply an index of embryo quality—e.g., embryos with chromosomal defects cannot manufacture sufficient quantities of the biochemical antecedents of pregnancy sickness to induce nausea and vomiting (Stein and Susser, 1991; Forbes, 2002). Chan et al. (2010) examined the link between pregnancy sickness, spontaneous abortion and maternal age. Intriguingly they found that an absence of pregnancy sickness was a much stronger predictor of spontaneous abortion in mothers over age 35 than for mothers under age 30. "
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    ABSTRACT: Nausea and vomiting of pregnancy (NVP) affects 90% of pregnant women and its impact is often underappreciated. Hyperemesis gravidarum, the most severe end of the spectrum, affects 0.5-2% of pregnancies. The pathogenesis of this condition remains obscure and its management has largely been empirical. This review aims to provide an update on advances in pregnancy hyperemesis focusing on papers published within the past 2 years. The cause of hyperemesis is continuing to be elaborated. Recent data attest to the effectiveness of the oral doxylamine-pyridoxine in NVP. Follow-up data of children exposed in early pregnancy to doxylamine-pyridoxine for NVP are reassuring. Evidence is increasing for ginger as an effective herbal remedy for NVP. Metoclopramide is effective in NVP and hyperemesis gravidarum, with a good balance of efficacy and tolerability. A recent large-scale study on first trimester exposure to metoclopramide is reassuring of its safety. Evidence is emerging for the treatment of acid reflux to ameliorate NVP. The role of corticosteroids for hyperemesis gravidarum remains controversial. Transpyloric feeding may be warranted for persistent weight loss, despite optimal antiemetic therapy. Women with significant NVP should be identified so that they can be safely and effectively treated.
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