Calculation of optimal gestation weight gain in pre-pregnancy underweight women due to body mass index change in relation to mother’s height

Maternal body mass index and risk of fetal overgrowth in women with gestational diabetes Mellitus in Southeast China: a retrospective cohort study

BACKGROUND

To investigate the relationship between body mass index (BMI) changes and large for gestational age (LGA) in women with gestational diabetes mellitus (GDM).

METHODS

A retrospective cohort study including 10,486 women with GDM was conducted. A dose‒response analysis of BMI changes and the occurrence of LGA was performed. Binary logistic regressions were performed to assess crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Receiver operating characteristic (ROC) curves and areas under the curve (AUCs) were used to assess the ability of BMI changes to predict LGA.

RESULTS

The probability of LGA increased with increasing BMI. The risk of LGA increased across the BMI change quartiles. The BMI change remained positively associated with the risk of LGAafter stratification analysis. The AUC was 0.570 (95% CI: 0.557 ~ 0.584)in the entire study population, and the best optimal predictive cut-off value was 4.922, with a sensitivity of 0.622 and a specificity of 0.486. The best optimal predictive cut-off value decreased from the underweight group to the overweight and obese group.

CONCLUSIONS

BMI changes are related to the risk of LGA and may be a useful predictor of the incidence of LGA in singleton pregnant women with GDM.

Optimal gestational weight gain in Chinese pregnant women by Chinese-specific BMI categories: a multicentre prospective cohort study

OBJECTIVE

To establish optimal gestational weight gain (GWG) in Chinese pregnant women by Chinese-specific BMI categories and compare the new recommendations with the Institute of Medicine (IOM) 2009 guidelines.

DESIGN

Multicentre, prospective cohort study. Unconditional logistic regression analysis was used to evaluate the OR, 95 % CI and the predicted probabilities of adverse pregnancy outcomes. The optimal GWG range was defined as the range that did not exceed a 1 % increase from the lowest predicted probability in each pre-pregnancy BMI group.

SETTING

From nine cities in mainland China.

PARTICIPANTS

A total of 3731 women with singleton pregnancy were recruited from April 2013 to December 2014.

RESULTS

The optimal GWG (ranges) by Chinese-specific BMI was 15·0 (12·8-17·1), 14·2 (12·1-16·4) and 12·6 (10·4-14·9) kg for underweight, normal weight and overweight pregnant women, respectively. Inappropriate GWG was associated with several adverse pregnancy outcomes. Compared with women gaining weight within our proposed recommendations, women with excessive GWG had higher risk for macrosomia, large for gestational age and caesarean section, whereas those with inadequate GWG had higher risk for low birth weight, small for gestational age and preterm delivery. The comparison between our proposed recommendations and IOM 2009 guidelines showed that our recommendations were comparable with the IOM 2009 guidelines and could well predict the risk of several adverse pregnancy outcomes.

CONCLUSIONS

Inappropriate GWG was associated with higher risk of several adverse pregnancy outcomes. Optimal GWG recommendations proposed in the present study could be applied to Chinese pregnant women.

Association of Pre-pregnancy BMI and Postpartum Weight Retention Before Second Pregnancy, Washington State, 2003-2013

Background Maternal overweight and obesity is one of the most common high-risk obstetric conditions associated with adverse birth outcomes. Smaller studies have suggested that pre-pregnancy body mass index (BMI) is associated with postpartum weight retention. Objective The primary objective of this study was to examine the association between pre-pregnancy BMI status and maternal weight retention. Study design We conducted a population-based retrospective cohort study using Washington State birth certificate data from 2003-2013. We included women who had two sequential births during this time period, with the second birth occurring within 18-36 months of the first singleton delivery date. BMI before a women's first pregnancy ("pre-pregnancy BMI") was categorized as normal (18.5-24.9 kg/m²) and overweight/obese (25-40 kg/m²). Women were classified as having returned to first pre-pregnancy BMI if their BMI before their second pregnancy was no more than 1 kg/m² more compared to their BMI before their first pregnancy. Analyses were stratified by gestational weight gain during the first pregnancy (below, met, exceeded recommended gestational weight gain). Results A total of 49,132 mothers were included in the study. Among women who met their recommended gestational weight gain, compared to mothers with a normal BMI, obese/overweight mothers were less likely to return to their pre-pregnancy BMI (76.5 vs 72.3%; RR_{Obese/Overweight} = 0.88; 95% CI: 0.85-0.92). A similar pattern was observed among women who exceeded their recommended gestational weight gain (62.6 vs 53.2%; RR_{Obese/Overweight} = 0.79, 95% CI: 0.78-0.80). Conclusion Pre-pregnancy BMI in the overweight/obese range is associated with a decreased likelihood of returning to pre-pregnancy BMI. Further research to support women during and after their pregnancy to promote behavior changes that prevent excessive weight gain during pregnancy and weight retention after birth is needed.

Increased retinol-free RBP4 contributes to insulin resistance in gestational diabetes mellitus

PURPOSE

Retinol-binding protein 4 (RBP4) is a circulating retinol transporter that is strongly associated with insulin resistance. The aim of this study was to evaluate the RBP4 and retinol level in rat model of gestational diabetes mellitus and the relationship between retinol-free RBP4 (apo-RBP4), retinol-bound RBP4 (holo-RBP4) and insulin resistance.

METHODS

Pregnant rats were administered streptozotocin to induce diabetes. The RBP4 and retinol levels were evaluated in GDM and normal pregnant rats. After then, normal pregnant rats were divided into two groups to receive either apo-RBP4 or vehicle injection. The metabolic parameters and insulin signaling in adipose tissue, skeletal muscle and liver were determined in apo-RBP4 and control groups. Primary human adipocytes were cultured in vitro with different proportions of apo-RBP4 and holo-RBP4 for 24 h. The interaction between RBP4 and STRA6 was assessed by co-immunoprecipitation, and the expression of JAK-STAT pathway and insulin signaling were detected by Western blotting and immunofluorescence.

RESULTS

We found increases in serum RBP4 levels and the RBP4:retinol ratio but not in the retinol levels in GDM rats. Exogenous apo-RBP4 injection attenuated insulin sensitivity in pregnant rats. In vitro, a prolonged interaction between RBP4 and STRA6 was observed when apo-RBP4 was present. In response to increased apo-RBP4 levels, cells showed elevated activation of the JAK2/STAT5 cascade and SOCS3 expression, decreased phosphorylation of IR and IRS1, and attenuated GLUT4 translocation and glucose uptake upon insulin stimulation.

CONCLUSION

Apo-RBP4 is a ligand that activates the STRA6 signaling cascade, inducing insulin resistance in GDM.