Evidence suggests a potential relationship between gestational weight gain (GWG) and adverse birth outcomes. However, the role of maternal genetic polymorphisms remains unclear. This study was conducted to investigate whether the relationship of GWG with risk of adverse birth outcomes was modified by methylenetetrahydrofolate reductase (MTHFR) polymorphisms. A total of 2,967 Chinese pregnant women were included and divided into insufficient, sufficient, and excessive groups based on the Institute of Medicine (IOM) criteria. Polymorphisms of C677T and A1298C in gene MTHFR were genotyped. Multivariable logistic regression models were introduced after controlling major confounders. Excessive GWG was found to increase the odds ratio (OR) for macrosomia [OR = 3.47, 95% confidence interval (CI): 1.86–6.48] and large-for-gestational age (LGA, OR = 3.25, 95% CI: 2.23–4.74), and decreased the OR for small-for-gestational age (SGA, OR = 0.60, 95% CI: 0.45–0.79). Pregnant women with insufficient GWG had a higher frequency of SGA (OR = 1.68, 95% CI: 1.32–2.13) and a lower rate of LGA (OR = 0.51, 95% CI: 0.27–0.96). Interestingly, significant associations of GWG categories in relation to low birth weight (LBW), macrosomia, and SGA were only suggested among pregnant women with MTHFR A1298C AA genotype. Among pregnant women with insufficient GWG group, an increased risk of 3.96 (95% CI: 1.57–10.01) for LBW was observed among subjects with the A1298C AA genotype, compared to the AC+CC genotype group. GWG categories are closely related to LBW, macrosomia, SGA and LGA, and the associations were modified by the polymorphism of MTHFR A1298C.

Background Increasing evidence suggests an association between maternal pre-pregnancy body mass index (pre-BMI) and adverse pregnancy outcomes. However, the effects of methylenetetrahydrofolate reductase (MTHFR) polymorphisms on these relationships require further investigation. This study aimed to investigate whether the relationship between pre-BMI and the risk of adverse pregnancy outcomes was influenced by MTHFR gene polymorphisms. Methods A total of 5614 mother-fetus pairs were included in the study. The odds ratios (OR) of adverse pregnancy complications, including gestational diabetes mellitus (GDM), gestational hypertension (GHT), cesarean delivery (CS), and premature rupture of membranes (PROM), were estimated using adjusted logistic regression models and subgroup analysis. Results Pregnant women with higher pre-BMI values were positively related to the risk of GDM, GHT, and CS. In the subgroup analysis, underweight BMI was associated with a decreased risk of CS and GDM in pregnant women with the MTHFR A1298C AA or C677T CC genotype, while overweight/obese BMI was associated with an increased risk of GDM and CS in different MTHFR variants. Moreover, pregnant women with MTHFR A1298C AC + CC or C667T CC were found to have an increased risk of GHT in the MTHFR A1298C AA or C667T CT + TT genotype. A remarkable association was observed between the obesity group with MTHFR A1298C AC + CC (OR = 6.49, CI: 2.67–15.79) and the overweight group with the C667T CC genotype (OR = 4.72, CI: 2.13–10.45). Conclusions MTHFR gene polymorphisms exert a modifying effect on the association between maternal pre-BMI and the risk of GHT, CS, and GDM. Pregnant women with a high pre-BMI with specific MTHFR genotypes should be considered for GHT development.

Background Group A streptococcal (GAS) toxic shock syndrome (TSS) is a rare invasive disease, causing a high risk of maternal and fetal mortality during pregnancy. We report a fatal case of a female caused by GAS-TSS in the third trimester of pregnancy in Guangzhou, China. Case presentation: The patient is a 33-year-old female who presented at 37 weeks’ gestation with a history of three hours fever. She underwent an emergency cesarean section due to fetal bradycardia. The neonate survived after an aggressive anti-infection treatment. However, the patient’s condition deteriorated rapidly after the operation and the patient died of disseminated intravascular coagulation and septic shock within 24h after admission. She was finally diagnosed with GAS-TSS. The GAS strains were isolated from two bottles of blood cultures, which confirmed as Streptococcus pyogenes by 16S gene sequencing and identified as serotype M1 by molecular typing. Conclusions Dramatical clinical picture and laboratory characters of the pregnant woman presented here might help improve clinicians' awareness and recognition of Streptococcus pyogenes, which could be of great importance for the early diagnosis of GAS- TSS in pregnancy.

Background: Group A streptococcal (GAS) toxic shock syndrome (TSS) is a rare invasive disease, causing a high risk of maternal and fetal mortality during pregnancy. We report a fatal case of a female caused by GAS-TSS in the third trimester of pregnancy in Guangzhou, China. Case presentation: The patient is a 33-year-old female who presented at 37 weeks’ gestation with a history of three hours fever. The patient underwent an early onset and rapid progression with dramatic clinical picture and laboratory characters within 24 hours. The neonate survived after an aggressive anti-infection treatment.The GAS strains were isolated from two bottles of blood cultures and airway secretion culture, which confirmed as Streptococcus pyogenes associated with genotype emm1 by molecular analysis.Conclusion: Dramatic clinical picture and laboratory characters of the pregnant woman presented here might help improve clinicians' awareness and recognition of Streptococcus pyogenes, which could be of great importance for the early diagnosis of GAS- TSS in pregnancy.

Background: Group A streptococcal (GAS) toxic shock syndrome (TSS) is a rare invasive disease, causing a high risk of maternal and fetal mortality during pregnancy. We report a fatal case of a female caused by GAS-TSS in the third trimester of pregnancy in Guangzhou, China. Case presentation: The patient is a 33-year-old female who presented at 37 weeks’ gestation with a history of three hours fever. The patient underwent an early onset and rapid progression with dramatic clinical picture and laboratory characters within 24 hours. The neonate survived after an aggressive anti-infection treatment.The GAS strains were isolated from two bottles of blood cultures and airway secretion culture, which confirmed as Streptococcus pyogenes associated with genotype emm1 by molecular analysis.Conclusion: Dramatic clinical picture and laboratory characters of the pregnant woman presented here might help improve clinicians' awareness and recognition of Streptococcus pyogenes, which could be of great importance for the early diagnosis of GAS- TSS in pregnancy.