Objective: To investigate the association between mid‐trimester residual cervical length (CL) and the risk of preterm birth in pregnancies after abdominal radical trachelectomy (RT).Design: Retrospective cohort study.Setting: University hospital.Population: A total of 33 deliveries after 22 weeks’ gestation in 30 women who underwent abdominal RT including prophylactic cervical cerclage and perinatal care between January 2002 and May 2016.Methods: The association between mid‐trimester residual CL (the distance between the cerclage and the external cervical os) and gestational age at delivery was investigated. Receiver–operating characteristics (ROC) curve analysis was performed to estimate the optimal cut‐off values of the mid‐trimester residual CL for the prediction of preterm birth.Main outcome measures: Preterm birth before 34 weeks’ gestation.Results: Mid‐trimester residual CL showed a significant correlation with gestational age at delivery (r = 0.36, P < 0.05). There was a significant difference in residual CL between women who did and those who did not give birth before 34 weeks (P < 0.05). Mid‐trimester residual CL < 13 mm was a good predictor of birth before 34 weeks, with a sensitivity of 67%, specificity of 75%, positive predictive value of 55% and negative predictive value of 86% (area under ROC curve, 0.75).Conclusions: Mid‐trimester residual CL is significantly correlated with gestational age at delivery. Residual CL assessment could be used to reassure physicians and women that there is only a small chance of preterm birth in pregnancies after abdominal RT.Tweetable Mid‐trimester residual cervical length is a good predictor of preterm birth after radical trachelectomy.

Gestational diabetes (GDM) and type 2 diabetes (T2DM) share part of pathomechanism and several T2DM susceptibility genes are demonstrated to be associated with GDM. No information on the genetics of GDM, however, was available in Japanese women. In this study, T2DM risk variants (45 single nucleotide polymorphisms [SNPs] from 36 genes) identified in previous studies were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in a cohort of 171 Japanese women with GDM and 128 normal glucose tolerance (NGT) diagnosed by the new International Association of Diabetes in Pregnancy Study Group criteria. Of 45 SNPs, three genetic variants were nominally associated with the development of GDM: rs266729 (p = 0.013, odds ratio [OR]: 1.56, 95% confidence interval [CI]: 1.10-2.23) in ADIPOQ, rs10811661 (p = 0.035, OR: 1.46, 95% CI: 1.03-2.08) in CDKN2A/2B, and rs9505118 (p = 0.046, OR: 1.41, 95% CI: 1.01-1.97) in SSR1-RREB1. There was a significant difference in the number of risk alleles of three variants between women with GDM and NGT (3.79 ± 1.33 vs. 3.05 ± 1.41, p = 6.0 × 10-6). In combined analysis of three genetic variants, women with five or more risk alleles had a 7.32-fold increased risk of GDM (p = 5.6 × 10-5, 95% CI: 4.54-11.96), compared with those having no more than one risk allele. Our results suggest several risk variants of T2DM had cumulative effects on the development of GDM in Japanese women.

Introduction: The average birth weight in Japan has gradually decreased and the number of low birth weight infant has increased over the last 30 years. Japanese pregnant women are characterized with lower prevalence of obesity than those in other developed countries, and maternal underweight before pregnancy is independently associated with low birth weight. However, the association between maternal inadequate gestational weight gain (GWG) and the risk of small for gestational age (SGA) in Japanese uncomplicated pregnant women has not been fully understood. This study aimed to examine the effect of maternal inadequate GWG on the risk of SGA in Japanese uncomplicated pregnancies. Methods: We retrospectively analyzed uncomplicated Japanese singleton pregnancies that delivered at term gestation in our institution from 2006 to 2016. The association between GWG and birth weight was analyzed by multiple linear regression. Potential confounding factors included maternal age, parity, prepregnancy BMI, and neonatal sex. The association between inadequate GWG and SGA was also examined by logistic regression. Results: A total of 3837 mother–neonate dyads were analyzed. Maternal GWG was 10.1 ± 3.7 kg (mean ± SD), and 2529 (66%) had inadequate GWG. After adjusting for confounding factors, GWG significantly correlated with birth weight (standardized β = 0.199, p < .001). Inadequate GWG increased the risk of delivering SGA neonate (adjusted odds ratio (aOR) = 1.97 [1.45–2.68], p < .001). This association was particularly pronounced in underweight (aOR = 2.95 [1.38–6.29], p = .005) and normal weight mothers (aOR = 1.79 [1.27–2.52], p = .001), and not in overweight/obese mothers (p = .115). Conclusion: Maternal GWG is associated with birth weight in Japanese women with uncomplicated singleton pregnancies. Inadequate GWG is an important risk factor of SGA, particularly in non-obese women. The present finding would potentially provide further evidence that promoting adequate gestational weight gain in Japanese underweight and normal weight mothers would reduce SGA, as well as metabolic dysfunction in later life.

Introduction: There is a paucity of data on the risk of preterm birth subcategorized by gestational age in pregnancies after the prepregnancy excisional treatment for cervical lesions. Additionally, little is known about the effect of prophylactic cerclage on the risk of preterm birth. The aim of this study was to investigate the risk of preterm birth stratified by gestational period and its reduction by the prophylactic cerclage in women with prior excisional surgery. Material and methods: We retrospectively analyzed a cohort of singleton pregnancies in the Japan Perinatal Registry Network Database (2013–2014, n = 307 001). Cases included pregnancies after the surgery (ie conization and loop electrosurgical excision procedure). Controls comprised the propensity-score matched pregnancies without prepregnancy surgery. The main outcome was the occurrence of preterm birth. The effect of prophylactic cervical cerclage on the risk of preterm birth after the excisional surgery was also examined using cases. Results: In the propensity-score matched population (cases, n = 1389; controls, n = 1389), cases exhibited higher risk of preterm birth and preterm prelabor rupture of membranes (PROM), compared with controls (preterm birth: 25.3 versus 10.6%; preterm PROM: 14.0 versus 3.5%: both p < 0.0001). Odds ratios (OR; 95% confidence interval [CI]) for preterm birth at 22–27 weeks, 28–31 weeks, 32–33 weeks, and 34–36 weeks were 3.4 [1.8–6.5], 4.6 [2.7–7.7], 2.2 [1.4–3.5], and 2.1 [1.6–2.7], respectively. The association was stronger for preterm PROM at earlier gestational age (22–27 weeks, 28–31 weeks, 32–33 weeks, and 34–36 weeks: 5.2 [2.3–11.8], 7.1 [3.4–15.0], 3.8 [1.7–8.3], and 3.9 [1.8–4.6], respectively). In cases, 171 underwent the prophylactic cervical cerclage. The occurrence of preterm birth and preterm PROM was comparable between those with and without the cerclage (28.7 versus 24.2, and 12.9 versus 13.3%, respectively). Conclusions: Prepregnancy excisional cervical surgery was associated with the increased risk of preterm birth, especially before 32 weeks of gestation. The prophylactic cerclage did not reduce the risk of preterm birth.

Aims/Introduction: Risk factors of type 2 diabetes mellitus in Japanese women with recent gestational diabetes mellitus are unknown. The objective of the present study was to investigate the clinical and genetic characteristics associated with postpartum abnormal glucose tolerance in Japanese women with gestational diabetes mellitus.Materials and Methods: A total of 213 Japanese women with recent gestational diabetes mellitus who underwent a postpartum 2‐h oral glucose tolerance test were investigated. The association between antepartum clinical characteristics and postpartum abnormal glucose tolerance (diabetes or prediabetes based on the Japan Diabetes Society criteria) was examined. Frequencies of 45 known type 2 diabetes mellitus‐associated genetic variants were also compared between women with and without postpartum abnormal glucose tolerance.Results: A total of 59 women showed postpartum abnormal glucose tolerance (prediabetes, n = 51; diabetes, n = 8). Plasma glucose levels at 1 or 2 h, the insulinogenic index and the insulin secretion‐sensitivity index‐2 of the antepartum oral glucose tolerance test were independent of postpartum abnormal glucose tolerance risk factors (P = 0.006, P = 0.00002, P = 0.01 and P = 0.006, respectively). Four genetic variants (rs266729 [ADIPOQ], rs6017317 [HNF4A], rs5215 [KCNJ11] and rs7177055 [HMG20A]) showed a nominally significant association with postpartum abnormal glucose tolerance (P < 0.05, respectively). Among these, three were related to insulin secretion. Postpartum abnormal glucose tolerance risk significantly increased with increasing risk‐allele number (P = 0.0005; odds ratio 1.91).Conclusions: Clinical features and genetic variants related to impaired insulin secretion are risk factors of postpartum abnormal glucose tolerance in Japanese women with recent gestational diabetes mellitus.