Demographic, clinical and occupational characteristics associated with early onset of delivery: findings from the Duke Health and Safety Surveillance System, 2001-2004

Development of placental abnormalities in location and anatomy

Low‐lying placentas, placenta previa and abnormally invasive placentas are the most frequently occurring placental abnormalities in location and anatomy. These conditions can have serious consequences for mother and fetus mainly due to excessive blood loss before, during or after delivery. The incidence of such abnormalities is increasing, but treatment options and preventive strategies are limited. Therefore, it is crucial to understand the etiology of placental abnormalities in location and anatomy. Placental formation already starts at implantation and therefore disorders during implantation may cause these abnormalities. Understanding of the normal placental structure and development is essential to comprehend the etiology of placental abnormalities in location and anatomy, to diagnose the affected women and to guide future research for treatment and preventive strategies. We reviewed the literature on the structure and development of the normal placenta and the placental development resulting in low‐lying placentas, placenta previa and abnormally invasive placentas.

The Relationship Between BMI and Work-Related Musculoskeletal (MSK) Injury Rates is Modified by Job-Associated Level of MSK Injury Risk

OBJECTIVE

The aim of this study was to examine the relationship between body mass index (BMI) and occupational musculoskeletal (MSK) injury rates, and the statistical interaction between BMI and occupational exposure to MSK hazards (measured by level of MSK injury risk based on job category).

METHODS

Using 17 years of data from 38,214 university and health system employees, multivariate Poisson regression modeled the interaction between BMI and MSK injury risk on injury rates.

RESULTS

A significant interaction between BMI and MSK injury risk was observed. Although the effect of BMI was strongest for 'low' MSK injury risk occupations, absolute MSK injury rates for 'mid'/'high' MSK injury risk occupations remained larger.

CONCLUSIONS

To address the occupational MSK injury burden, initiatives focused on optimal measures of workers' BMI are important but should not be prioritized over (or used in lieu of) interventions targeting job-specific MSK injury hazards.

Comparison of medical issues in antenatal and perinatal periods in early youth, adolescent, and young adult mothers in Taiwan: a 10-year nationwide study

BACKGROUND

Limited information is available concerning investigating the separate effect of teenage childbirth on medical issues in the antenatal and perinatal periods. Therefore, this study aimed to assess medical problems in antenatal and perinatal periods among early youth, adolescent and young adult mothers in Taiwan.

METHODS

This retrospective population-based cohort study was conducted by using data from Taiwan's National Health Insurance Research Database. A total of 335,590 mothers aged less than 25 years who had singleton births were identified between 2002 and 2011. Univariate and multivariate logistic regression analyses were conducted to estimate unadjusted and adjusted odds ratios (OR) and 95% confidence intervals (CI) of each medical problem category in the antenatal and perinatal periods.

RESULTS

Compared with mothers aged 20-24 years, adolescents (16-19 years) and early youth mothers (≤ 15 years), particularly those aged 10-15, had a significantly higher risk of intrauterine growth retardation (IUGR, OR = 1.37, 95% CI: 1.00-1.89) and preterm delivery (OR = 2.98, 95% CI: 2.48-3.58) after adjusting for demographic characteristics and clinical factors. Additionally, adolescents mothers were at an increased risk of anemia (OR = 1.32, 95% CI: 1.24-1.40), oligohydramnios (OR = 1.21, 95% CI: 1.12-1.32), failed labor induction (OR = 1.33, 95% CI: 1.24-1.43), and fetal distress (OR = 1.20, 95% CI: 1.14-1.26) after adjustment.

CONCLUSIONS

Not all young mothers in our study experienced the same magnitude of increased medical problems in the antenatal and perinatal periods. However, a sufficiently higher probability of having IUGR and preterm delivery was observed among early youth and adolescent mothers.

Vitamin D receptor polymorphism FokI is associated with spontaneous idiopathic preterm birth in an Israeli population

OBJECTIVE

The active form of vitamin D (1,25[OH]2D3) has been established to have potent anti-proliferative, immuno-modulatory, and anti-microbial action in addition to its effects on bone. The nuclear vitamin D receptor (VDR) is expressed in the placenta-decidua, regulating genes associated with implantation and implantation immuno-tolerance. If VDR polymorphisms regulate VDR functionality at the placenta-decidua interface, VDR genotypes may be involved in idiopathic preterm birth (PTB).

STUDY DESIGN

Maternal and fetal (umbilical cord) blood samples from 33 Jewish and Arab mothers with PTB of a singleton neonate were compared to 98 samples from Jewish and Arab maternal and fetal blood samples from full-term, uncomplicated singleton births. Maternal age and ethnicity were comparable between groups. PCR amplification/digestion identified the VDR SNPs: FokI, ApaI, TaqI, and BsmI.

RESULTS

Allele frequency for the FokI VDR in maternal blood samples from preterm births (but not umbilical cord samples) was significantly different (p=0.01) from that in maternal and umbilical cord blood samples from full-term singleton births, with an odds ratio for FokI carriers of 3.317 (95% CI, 1.143, 9.627) for preterm birth. The FokI VDR variant may therefore be a maternal risk trait for PTB among these women.

CONCLUSION

This study may support a future platform for the study of vitamin D during pregnancy and treatment of selective target populations with vitamin D and/or VDR "tissue-specific therapeutic intervention" for prevention of PTB.

Preterm birth and prenatal maternal occupation: the role of Hispanic ethnicity and nativity in a population-based sample in Los Angeles, California

OBJECTIVES

We investigated preterm birth (PTB) in relation to maternal occupational exposure and whether effect measures were modified by Hispanic ethnicity and nativity in a population-based sample with high proportion of Hispanics.

METHODS

We used a case-control study (n = 2543) nested within a cohort of 58,316 births in Los Angeles County, California, in 2003. We categorized prenatal occupations using the US Census Occupation Codes and Classification System and developed a job exposure matrix. Odds ratios for PTB were estimated using logistic regression.

RESULTS

Odds ratios for PTB were increased for all women in health care practitioner and technical occupations, but the 95% confidence intervals included the null value; effects were more pronounced among Hispanics. We estimated elevated odds ratios for foreign-born Hispanic women in building and grounds cleaning and maintenance occupations. Shift work and physically demanding work affected births among US-born but not foreign-born Hispanics.

CONCLUSIONS

Hispanic women are at particular risk for PTB related to adverse prenatal occupational exposure. Nativity may moderate these effects on PTB. Maternal occupational exposures likely contribute to ethnic disparities in PTB.

Psychometric testing of the modified breastfeeding self-efficacy scale (short form) among mothers of ill or preterm infants

OBJECTIVE

To psychometrically assess the modified Breastfeeding Self-Efficacy Scale-Short Form (BSES-SF) among mothers of ill or preterm infants.

DESIGN

Methodological study.

SETTING

Three neonatal intensive care units (NICUs) located in two hospitals in a central Canadian city.

PARTICIPANTS

One hundred forty-four (144) breastfeeding mothers of ill or preterm infants.

METHODS

Mothers completed the BSES-SF modified for mothers of ill or preterm infants, the Hill and Humenick (H&H) Lactation Scale, and demographic questions.

RESULTS

The Cronbach's alpha coefficient for internal consistency for the BSES-SF revised for mothers of ill or preterm infants was 0.88. Construct validity was assessed using comparison of contrasted groups (mothers who continued to breastfeed and those who discontinued) and correlation with the construct of maternal perceptions of insufficient milk supply. Support for predictive validity was demonstrated through significant mean differences between mothers who were breastfeeding (M = 83.44, SD = 8.23) and those who discontinued breastfeeding and breast pumping (M = 75.51, SD = 10.08) at 6-weeks post-infant hospital discharge.

CONCLUSION

Demographic response patterns suggest that the modified BSES-SF is a unique tool to identify breastfeeding mothers of ill or preterm infants at risk of prematurely discontinuing. This study provides evidence that the modified BSES-SF may be a valid and reliable measure of breastfeeding self-efficacy among a sample of mothers of ill or preterm infants.