Families with a perinatal death: is there an association between the loss and the birthweight of surviving siblings?

Association between parity and macrosomia in Shaanxi Province of Northwest China

OBJECTIVE

To explore the relationship between parity and macrosomia and provide the necessary reference for the maternal and children health service.

METHOD

A cross-sectional epidemiological survey with the purpose to assess the birth outcomes was conducted in Shaanxi province, China.

RESULTS

The incidence of macrosomia in multiparas was higher than that in primiparas. Univariate analysis showed that maternal age < 25 years, peasant/housework, living in rural areas and female infants were the protective factors of macrosomia. The possibility of having a macrosomic infant also increased with gestational age, maternal education level, household wealth index, living in Central Shaanxi and gestational diabetes. The generalized linear mixed models represented the association between parity and macrosomia. After adjusting for statistically significant factors in univariate analysis from model 1 to model 3, the risk of being born macrosomia was 1.26 times higher for a multipara compared to that for a primipara.

CONCLUSIONS

Present study indicated parity of two children was associated with increased risk for macrosomic births compared with parity of one child. Compared to primiparas, multiparas should far strengthen the pre-pregnancy education and the guidance during pregnancy to control pre-pregnancy body mass index and pregnancy weight, and keep the appropriate exercise and balanced diet.

The effect of social behavior change communication package on maternal knowledge in obstetric danger signs among mothers in East Mamprusi District of Ghana

Background

An understanding of maternal knowledge of the danger signs of obstetric and newborn complications is fundamental to attaining universal health coverage. In Northern Ghana, where maternal and newborn morbidity and mortality is high, little is known about the current knowledge level and associated determinants of these danger signs. This study assessed the effect of social behavior change communication (SBCC) package on knowledge of obstetric and newborn danger signs among mothers with children under 24 months of age.

Methods

This study used a non-randomized controlled community-based intervention design with pre and post-intervention household surveys in the intervention and comparison communities of the East Mamprusi District in Ghana. The study population were selected using a two-stage cluster sampling procedure.

Result

Only 521 (51.1%), 300 (29.4%) and 353 (34.6%) of the study participants knew at least three key danger signs during pregnancy, delivery and postpartum period respectively.

The intervention had a positive effect on maternal knowledge of danger signs. Compared to their counterparts in the comparison communities, women in the intervention communities were about 2.6 times (AOR  =  2. 58 [CI: 1.87, 3.57]), 3.4 times (AOR  =  3.39 [CI: 2.31, 4.96]) and 2.2 times (AOR  =  2.19 [CI: 1.68, 2.84]) more likely to have higher knowledge of danger signs of childbirth, postpartum and neonate, respectively.

Having sought postnatal services at least once was significantly associated with the mentioning of at least three danger signs of postpartum (AOR  =  3.90 [CI: 2.01, 7.58]) and childbirth (AOR  =  1.75 [CI: 1.06, 2.85]).

Conclusion

There was a significant contribution of social and behavioral change communication as an intervention to maternal knowledge in obstetric danger signs after adjusting for confounding factors such as antenatal and post-natal care attendance. Therefore, provision of information, education and communication targeting women on danger signs of pregnancy and childbirth and associated factors would be an important step towards attaining universal health coverage.

High birth weight and perinatal mortality among siblings: A register based study in Norway, 1967-2011

BACKGROUND

Perinatal mortality according to birth weight has an inverse J-pattern. Our aim was to estimate the influence of familial factors on this pattern, applying a cohort sibling design. We focused on excess mortality among macrosomic infants (>2 SD above the mean) and hypothesized that the birth weight-mortality association could be explained by confounding shared family factors. We also estimated how the participant's deviation from mean sibling birth weight influenced the association.

METHODS AND FINDINGS

We included 1 925 929 singletons, born term or post-term to mothers with more than one delivery 1967-2011 registered in the Medical Birth Registry of Norway. We examined z-score birth weight and perinatal mortality in random-effects and sibling fixed-effects logistic regression models including measured confounders (e.g. maternal diabetes) as well as unmeasured shared family confounders (through fixed effects models). Birth weight-specific mortality showed an inverse J-pattern, being lowest (2.0 per 1000) at reference weight (z-score +1 to +2) and increasing for higher weights. Mortality in the highest weight category was 15-fold higher than reference. This pattern changed little in multivariable models. Deviance from mean sibling birth weight modified the mortality pattern across the birth weight spectrum: small and medium-sized infants had increased mortality when being smaller than their siblings, and large-sized infants had an increased risk when outweighing their siblings. Maternal diabetes and birth weight acted in a synergistic fashion with mortality among macrosomic infants in diabetic pregnancies in excess of what would be expected for additive effects.

CONCLUSIONS

The inverse J-pattern between birth weight and mortality is not explained by measured confounders or unmeasured shared family factors. Infants are at particularly high mortality risk when their birth weight deviates substantially from their siblings. Sensitivity analysis suggests that characteristics related to maternal diabetes could be important in explaining the increased mortality among macrosomic infants.

The association between parity and birthweight in a longitudinal consecutive pregnancy cohort

BACKGROUND

Nulliparity is associated with lower birthweight, but few studies have examined how within-mother changes in risk factors impact this association.

METHODS

We used longitudinal electronic medical record data from a hospital-based cohort of consecutive singleton live births from 2002-2010 in Utah. To reduce bias from unobserved pregnancies, primary analyses were limited to 9484 women who entered nulliparous from 2002-2004, with 23,380 pregnancies up to parity 3. Unrestricted secondary analyses used 101,225 pregnancies from 45,212 women with pregnancies up to parity 7. We calculated gestational age and sex-specific birthweight z-scores with nulliparas as the reference. Using linear mixed models, we estimated birthweight z-score by parity adjusting for pregnancy-specific sociodemographics, smoking, alcohol, prepregnancy body mass index, gestational weight gain, and medical conditions.

RESULTS

Compared with nulliparas', infants of primiparas were larger by 0.20 unadjusted z-score units [95% confidence interval (CI) 0.18, 0.22]; the adjusted increase was similar at 0.18 z-score units [95% CI 0.15, 0.20]. Birthweight continued to increase up to parity 3, but with a smaller difference (parity 3 vs. 0 β = 0.27 [95% CI 0.20, 0.34]). In the unrestricted secondary sample, there was significant departure in linearity from parity 1 to 7 (P < 0.001); birthweight increased only up to parity 4 (parity 4 vs. 0 β = 0.34 [95% CI 0.31, 0.37]).

CONCLUSIONS

The association between parity and birthweight was non-linear with the greatest increase observed between first- and second-born infants of the same mother. Adjustment for changes in weight or chronic diseases did not change the relationship between parity and birthweight.

Association between short interpregnancy intervals and term birth weight: the role of folate depletion

BACKGROUND

Maternal folate depletion has been proposed as a primary explanation for the excess risk of fetal growth restriction associated with short interpregnancy intervals.

OBJECTIVE

We aimed to evaluate the folate depletion hypothesis in a community-based cohort of pregnant women.

DESIGN

Using a subsample of the cohort (multiparous participants who delivered a liveborn singleton infant, n = 3153), we investigated the relation between an increase in the interpregnancy interval (from 1 to 24 mo, natural log transformation) and birth weight and the risk of small-for-gestational-age (SGA) in 3 strata of maternal periconceptional folic acid use: nonuse, late use (begun after conception), and early use (begun before conception).

RESULTS

Each increase in the interpregnancy interval on the natural log (ln) scale was associated with a mean (+/-SE) increase of 63.1 +/- 20.3 g in birth weight (P = 0.002). This relation was mitigated by folic acid use: the change in birth weight was increases of 165.2 +/- 39.6 g for nonuse (P < 0.001) and 33.5 +/- 35.6 g for late use (P = 0.347) and a decrease of 5.9 +/- 33.6 g for early use (P = 0.861). The birth weight differences were directly translated into SGA risk. Odds ratios per 1-mo increase in ln(interpregnancy interval) were significant for the total group (0.61; 95% CI: 0.46, 0.82) and for nonuse (0.38; 0.24, 0.60) and nonsignificant for late (0.83; 0.48, 1.44) and early (1.28; 0.58, 2.84) use.

CONCLUSIONS

Folate depletion apparently contributes to the excess risk of fetal growth restriction that is associated with short interpregnancy intervals. As a preventive option, postnatal supplementation may be beneficial, but confirmation is needed.

Organizing population data into complex family pedigrees: application of a second-order data linkage to state birth defects registries

Researchers and health officials are increasingly using electronic linkage of large-scale health data systems as a tool for assembling a comprehensive picture of birth defects at a population level. Current linkage and database techniques are limited to first-order linkage--linking information on a single individual in one database with information on that same individual in another database. For example, while current strategies may indicate whether a child with a certain birth defect also has a specific metabolic disorder or risk factor, they are unable to readily determine whether he or she also has any siblings or other relatives with the same pattern. In contrast, the current manuscript proposes a second-order linkage--one that organizes data so that individual-level data can readily be organized into families or extended family pedigrees across an entire population. The ability to link and organize population data into family pedigrees can have significant, broad impact upon health research and service delivery. This can lead to large-scale analysis of genetic factors and, with the linking of environmental data, the potential for large-scale studies of gene-environment interactions. In addition, it expands the potential for epidemiological research by readily allowing the examination of familial effects upon population rates of birth defects, and provides valuable information that can assist in applied public health. An example of a second order database incorporating an electronic birth defects registry is presented.