Environmental pollutant exposure may play certain roles in the pathogenesis and progression of diabetes mellitus including gestational diabetes mellitus (GDM). We hypothesize that heavy metal exposure may trigger GDM during pregnancy. The objective of this study was to investigate the possible associations between selected heavy metal exposure and GDM risk. This investigation is a retrospective case–control study nested within a cohort of 1359 pregnant women. These participants were recruited in Xiamen Maternity and Child Care Hospital, China, during June to July, 2012. All their newborns’ meconium samples were collected. By reviewing the antenatal care records, 166 GDM mothers were screened out from the 1359 participants; 137 of 166 GDM mothers offered their newborns’ meconium samples for the metal analysis. Those 137 mothers were set as the case group. Similarly, 294 healthy mothers without any gestational complication were initially screened out from the rest 1193 non-GDM mothers. 190 of the 294 healthy mothers offered their newborns’ meconium samples for the metal analysis. Those 190 mothers were set as the control group. Arsenic (As), mercury (Hg), lead (Pb), cadmium (Cd), and chromium (Cr) levels in these case–control meconium samples were measured by inductively coupled plasma mass spectrometry. The possible association between the metal levels and maternal GDM risk of studied subjects was assessed by binary logistic regression. GDM prevalence of 12.21% was observed in the investigated 1359 participants. The concentrations of As, Hg, Cr and Cd in studied cases were significantly higher (p < 0.05) than those of controls. After adjustments for maternal age, pre-pregnant body mass index, gravidity, parity, hepatitis B virus infection, and newborn sex, As, Cd and Cr were found to be positively associated with GDM prevalence in dose-dependent manners. Among them, As was detected in all samples and its levels associated the maternal GDM with the adjusted odds ratios of 3.28 [95% CI 1.24, 8.71], 3.35 [95% CI 1.28, 8.75] and 5.25 [95% CI 1.99, 13.86] for the 2nd, 3rd and 4th quartiles, respectively. The present work implies that exposure to some of the selected metals (noticeably As) may contribute to maternal GDM risk during pregnancy.

Gestational diabetes mellitus (GDM) is a typical fetus development niches dysfunction and many toxic/nutrient elements have been associated with its onset and progression. However, the classic epidemiologic approach is regarded as "black-box epidemiology" and fails to elucidate these elements' biological roles on the damaged fetus developmental microenvironment. We aimed to characterize the associations between meconium of multiple elements with GDM for illustrating their interruption effects on in-uterus microenvironment. In this case-control study (n = 137 cases; n = 197 controls), the participants were nested from a cross-sectional retrospection of 1359 recruitments in Xiamen, China. Twenty-one meconium elements were characterized using inductively coupled plasma mass spectrometry (ICP-MS) or inductively coupled plasma optical emission spectrometry (ICP-OES). For shifting the present paradigm from a black-box approach to a molecular approach, GDM-related metabolic markers were identified in our previous metabolome report. Based on the meet-in-middle strategy, the associations among the elements, metabolic markers and GDM incidence were assessed by using redundancy analysis and correlation-adjusted correlation; mediation analysis was further used to test the hypothesis that metabolic markers mediate the associations of the elements with GDM incidence. Eight elements were related with the GDM occurrence in dose-dependent manners, which positively (Al, As, Ba, Cd, Hg, and Sn) or negatively (Ca and V) associated with GDM. Among them, As, Cd, Ba, and Ca significantly contributed to the variation of GDM-related metabolic markers. Additionally, the associations of Cd, Ba, Ca and As with GDM were mediated by the metabolic markers which majorly involved in the lipid metabolism and the Adenosine/l-Arginine/Nitric Oxide (ALANO) pathways. The two-side mediations of meconium metabolic markers between the multiple elements and GDM occurrence indicated that maternal exposure to As, Ba, Cd, and Ca may be associated with the dysfunction of fetus development niche through disrupting lipid metabolism and ALANO pathways.

Although the presence of live microbes in utero remains under debate, newborn gastrointestinal bacteria are undoubtedly important to infant health. Measuring bacteria in meconium is an ideal strategy to understand this issue; however, the low efficiency of bacterial DNA extraction from meconium has limited its utilization. This study aims to improve the efficiency of bacterial DNA extraction from meconium, which generally has low levels of microflora but high levels of PCR inhibitors in the viscous matrix. The research was approved by the ethical committee of the Xiamen Maternity and Child Health Care Hospital, Xiamen, China. All the mothers delivered naturally, and their newborns were healthy. Meconium samples passed by the newborns within 24 h were collected. Each sample was scraped off of a sterile diaper, transferred to a 5-ml sterile tube, and stored at −80°C. For the assay, a freeze-thawing sample preparation protocol was designed, in which a meconium-InhibitEX buffer mixture was intentionally frozen 1–3 times at −20°C, −80°C, and (or) in liquid nitrogen. Then, DNA was extracted using a commercial kit and sequenced by 16S rDNA to verify the enhanced bacterial DNA extraction efficiency. Ultimately, we observed the following: (1) About 30 mg lyophilized meconium was the optimal amount for DNA extraction. (2) Freezing treatment for 6 h improved DNA extraction at −20°C. (3) DNA extraction efficiency was significantly higher with the immediate thaw strategy than with gradient thawing at −20°C, −80°C, and in liquid nitrogen. (4) Among the conditions of −20°C, −80°C, and liquid nitrogen, −20°C was the best freezing condition for both improving DNA extraction efficiency and preserving microbial species diversity in meconium, while liquid nitrogen was the worst condition. (5) Three freeze-thaw cycles could markedly enhance DNA extraction efficiency and preserve the species diversity of meconium microflora. We developed a feasible freeze-thaw pretreatment protocol to improve the extraction of microbial DNA from meconium, which may be beneficial for newborn bacterial colonization studies.

Rationale: The umbilical cord is the way to exchange gas, supply nutrients, excrete metabolized. Thrombosis of the umbilical cord leads to fetal hypoxia, which jeopardizes fetal health and can cause fetal death. Umbilical vessel thrombosis, which is rarely reported, is difficult to detect prenatally. Patient concerns: Both pregnant women had an unremarkable pregnancy course until a routine ultrasound scan in the third trimester showed a single umbilical artery. However, one umbilical vein and 2 umbilical arteries were seen during an ultrasound examination at 32 weeks. Case 2 had a better pregnancy outcome because of the timely discovery of this complication. Diagnosis: Both cases were diagnosed as umbilical artery thrombosis. Interventions: The first patient received no interventions until they reported decreased fetal movements and gradually disappear. The second patient underwent an emergency cesarean section. Outcomes: In Case 1, an emergency ultrasound examination showed intrauterine fetal death, and the patient vaginally delivered a stillborn child weighing 3300 g in a day. In Case 2, a female neonate weighing 2860 g was delivered by cesarean section, and exhibited Apgar scores of 10 and 10 at 1 and 5 minutes. Conclusion: In the late-term abortions, obstetricians should be vigilant if ultrasound imaging shows suspected umbilical vascular thrombosis or shows 1 umbilical artery when there had previously been 2. The fetus should be closely monitored and interventions implemented as early as possible to improve the prenatal detection rate of umbilical vessel thrombosis and avoid adverse pregnancy outcomes.

Objective: To investigate the diagnosis, treatment, and maternal and fetal outcomes of placental abruption. Materials and methods: We recruited 585 cases of placental abruption from the Women and Children’s Hospital Affiliated to Xiamen University between January 2012 and December 2017. Cases were categorized into four groups (class 0–III) according to the clinical guidelines published by the Obstetrics and Gynecology Branch of the Chinese Medical Association. We then compared clinical data and auxiliary examinations across the four groups. Results: The differences were statistically significant (p < .01) among the four groups of placental abruption with regard to the incidence of an abnormal ultrasound finding. Positive ultrasound signs were evident in 6.4% of the patients categorized as class 0 and 100.0% of patients categorized as class III. Monitoring showed that fetal heart rate (FHR) was abnormal in class II patients with placental abruption; patients in class III showed no fetal heart sounds. Cesarean section was carried out for 26.6%, 75.1%, 65.2%, and 47.1% of patients in classes 0, I, II, and III, respectively. The rate of cesarean section for classes I and II was the highest, while the lowest rate occurred for class 0. Postpartum hemorrhage occurred in 2.5%, 9.3%, 15.2%, and 29.4% of patients across the four groups, DIC occurred in 0.0%, 1.3%, 2.3%, and 23.5% of cases, and perinatal death occurred in 1.0%, 1.3%, 7.6%, and 100.0% of cases, respectively. The highest incidence of postpartum hemorrhage was in class III (29.4%) and the lowest was in class 0 (2.5%). The highest incidence of DIC was in class III (23.5%) and the lowest was in class 0 (0.0%). The highest incidence of neonatal asphyxia was in class II (34.1%) and the lowest was in class 0 (10.1%). Regarding perinatal death, the highest incidence was in class III (100.0%) and the lowest was in class 0 (1.0%). These data showed significance differences when compared across the four groups of patients (p < .01). Conclusions: We recommend that the diagnosis of placental abruption should consider risk factors, clinical features, FHR monitoring, and dynamic ultrasound monitoring. Early diagnosis and treatment can improve maternal and infant prognosis.