Relationship between hyperemesis gravidarum and small-for-gestational-age in the Japanese population: the Japan Environment and Children’s Study (JECS)

Abstract

BackgroundSmall-for-gestational-age in infancy is a known risk factor not only for short-term prognosis but also for several long-term outcomes, such as neurological and metabolic disorders in adulthood. Previous research has shown that severe nausea and vomiting in early pregnancy (NVP) and hyperemesis gravidarum, which is an extreme form of NVP, represent risk factors for small-for-gestational-age birth. However, there is no clear consensus on this association. Thus, in the present study, we investigated the correlation between hyperemesis gravidarum and NVP on the one hand, and infant birth weight on the other, using data from the Japan Environment and Children’s Study (JECS).MethodsThe data utilized in the present study were obtained from the JECS, an ongoing cohort study that began in January 2011. Our sample size was 8635 parent–child pairs. The presence or absence of severe NVP, hyperemesis gravidarum, and potential confounding factors were noted. A multivariable regression analysis was used to estimate risks for small-for-gestational-age birth, and the results were expressed as risk ratios and 95 % confidence intervals.ResultsThe risk ratios of small-for-gestational-age birth (95 % confidence interval) for mothers with severe NVP and those with hyperemesis gravidarum were 0.86 (0.62–1.19) and 0.81 (0.39–1.66), respectively, which represents a non-significant result.ConclusionsIn our analysis of JECS data, neither severe NVP nor hyperemesis gravidarum was associated with increased risk for small-for-gestational-age birth.

Maternal sleep and small for gestational age infants in the Japan Environment and Children’s Study: a cohort study

“…The means of maternal age, gestational age at birth, and birth weight were 30.6 ± 4.98 years, 39.0 ± 1.14 weeks, and 3051 ± 369.85 g, respectively. Results of the univariate analysis for birth weight, which accounted for confounding background and social factors, are shown in a table in the previous article [ 5 ].…”

“…After excluding missing data and premature birth, we analyzed the data of the remaining 8631 women who had singleton, full-term (≥37 weeks, but <42 weeks) pregnancies (Fig. 1 of the previous article [ 5 ]). The present study is based on the dataset of jecs-ag-ai-20131008, which was released in October 2013.…”

“…Although several risk factors for SGA have been identified, some remain unknown. In our previous study, the analysis of the Japan Environment and Children’s Study (JECS) data set showed that neither severe nausea nor vomiting in early pregnancy nor hyperemesis gravidarum was associated with an increased risk for SGA birth [ 5 ].…”

Nausea, vomiting and poor appetite during pregnancy and adverse birth outcomes in rural Nepal: an observational cohort study

“…(31) Another study showed an increased risk of SGA in women who had hyperemesis gravidarum during pregnancy, but studies on the effects of milder symptoms have shown either a protective effect of nausea and vomiting of pregnancy or no difference. (4,29,30) Of note, these studies all took place in high-income countries. On the other hand, studies in high-income settings have showed a signi cantly increased risk of LBW and SGA in women with hyperemesis gravidarum.…”

Nausea, vomiting and poor appetite during pregnancy and adverse birth outcomes in rural Nepal: an observational cohort study

“…Another study showed an increased risk of SGA in women who had hyperemesis gravidarum during pregnancy, but studies on the effects of milder symptoms have shown either a protective effect of NV of pregnancy or no difference. (4,24,25) However, these studies all took place in high-income countries. On the other hand, studies in high-income settings have showed a significantly increased risk of LBW and SGA in women with hyperemesis gravidarum.…”