Gestational diabetes mellitus (GDM) is a common complication of pregnancy, and previous studies have shown that pregnant women with GDM have a higher risk of developing infectious diseases of the reproductive tract than healthy pregnant women, but relevant cohort studies are rare.
To investigate the variation characteristics of vaginal microbiota in pregnant women with GDM at different gestational weeks, to compare the differences of vaginal microbiota between GDM and non-GDM women, and to observe the effects of vaginal microbiota changes on pregnancy outcomes.
In this study, we used a consecutive sampling method to recruit pregnant women who established their records and regulated health care at Daxing Teaching Hospital of Capital Medical University from March 2022 to March 2023. They underwent 75 g oral glucose tolerance test (OGTT) at 24-28 weeks of gestation to diagnose GDM. The GDM group was matched 1∶1 with the non-GDM group using propensity score matching method (PSM). Sample of vaginal secretions were collected at 24-28 weeks (stage A), 32-35 weeks (stage B) and 37-40 weeks (stage C) for three vaginal microecological examination, respectively. Based on the results, participants were further divided into the GDM normal vaginal flora subgroup, GDM abnormal vaginal flora subgroup, non-GDM normal vaginal flora subgroup and non-GDM abnormal vaginal flora subgroup, and were followed up until 7 d after delivery to assess pregnancy outcome.
A total of 426 participants were initially enrolled in this study, and GDM occurred in 141 cases. After PSM mathing, the GDM and non-GDM groups were successfully matched in 122 pairs. In this study, because 9 women with GDM and 5 women without GDM had preterm birth (<37 weeks of gestation), 113 women with GDM and 117 women without GDM ended up in stage C. The proportion of the dominant vaginal flora of Lactobacillus was higher in stage A than in stage C. Moreover, the vaginal pH, the incidence of vaginal flora abnormalities, and the incidence of BV and VVC were lower than those in stage C (P<0.05). The proportion of dominant bacteria as Lactobacillus in the GDM group was higher than that in the non-GDM group, and the incidence of abnormal vaginal flora and VVC was lower than that in the non-GDM group in stage A (P<0.05). In contrast, the proportion of the dominant bacterium Lactobacillus was lower in the GDM group than in the non-GDM group, and the incidence of abnormal vaginal flora was higher than in the non-GDM in stage C (P<0.05). The incidence of adverse pregnancy outcomes was higher in the GDM abnormal vaginal flora subgroup (n=65) than in the GDM normal vaginal flora subgroup (n=57) (P<0.05). In more details, the risk of adverse pregnancy outcomes in the GDM abnormal vaginal flora group was 1.830 times higher than that in the GDM normal vaginal flora group (RR=1.830, 95%CI=1.293-2.590, P<0.001) .
Compared with non-GDM pregnant women, GDM pregnant women had a lower incidence of vaginal flora abnormalities at 24-28 weeks of gestation and an increased risk of vaginal flora abnormalities after 37 weeks of gestation. GDM pregnant women with abnormal flora have higher risk of adverse pregnancy outcomes, so we recommend enhanced testing and management of vaginal microecology during pregnancy.
Thyroid hormones are very important for normal growth and development of fetus. Hypothyroidism during pregnancy and Graves' hyperthyroidism in pregnancy are well-known risk factors for small for gestational age (SGA). However, the influence of isolated maternal hypothyroxinemia (IMH) in the first trimester during pregnancy on birthweight is less analyzed and controversial.
To examine the correlation of IMH in the first trimester during pregnancy with birthweight.
This was a retrospective cohort study involving singleton pregnant women with medical files and receiving prenatal examination, delivery or termination of pregnancy in the Beijing Obstetrics and Gynecology Hospital, Capital Medical University from January 2016 to October 2020. According to the 2.5th and 97.5th percentiles of free thyroxine (FT4) and thyroid stimulating hormone (TSH), participants were assigned into IMH group (n=344) and control group (n=19 426). Binary Logistic regression was used to analyze the correlation of IMH in the first trimester during pregnancy with birthweight. Then according to the pre-pregnancy body mass index (PPBMI), participants were assigned into the overweight/obesity group (PPBMI≥24.0 kg/m2, 69 cases in IMH group and 3 376 cases in control group) and non-overweight/obesity group (PPBMI<24.0 kg/m2, 275 cases in IMH group and 16 050 cases in control group). The pregnancy outcomes of different groups were compared and the relationship between IMH and pregnancy outcomes was compared.
The results of multivariate Logistic regression analysis showed that, the incidence of macrosomia and large for gestational age (LGA) in the IMH group was 1.627 times (OR=1.627, 95%CI=1.103-2.399, P=0.014) and 1.681 times higher than the control group (OR= 1.681, 95%CI=1.288-2.196, P<0.001), respectively. However, there were no significant differences in the incidences of low birth weight (LBW) and SGA between the two groups (P>0.05). Among participants with PPBMI<24.0 kg/m2 (non-overweight/obesity group), the incidence of macrosomia and LGA in the IMH group was 2.021 times (OR=2.021, 95%CI=1.320-3.093, P=0.001) and 1.788 times (OR=1.788, 95%CI=1.322-2.418, P<0.001) higher than the control group, respectively. Among participants with PPBMI≥24.0 kg/m2 (overweight/obesity group), there were no significant differences in the incidences of macrosomia, LBW, LGA and SGA between the two groups (P>0.05) .
IMH in the first trimester increases the risks of macrosomia and LGA during pregnancy, especially in pre-pregnancy non-overweight/obese women. Among pre-pregnancy overweight /obese women, IMH in the first trimester does not increase the risks of macrosomia and LGA. However, the incidences of LBW and SGA are comparable in the total cohort, women with pre-pregnancy overweight/obese or those without pre-pregnancy overweight/obese.
Gestational diabetes mellitus (GDM) is closely related to the short-term and long-term health outcomes of the mothers and offspring. Pre-pregnancy BMI is strongly associated with GDM, nevertheless, it does not distinguish between body fat content and fat distribution. Only using it to assess obesity is flawed. Normal weight obesity (normal BMI but body fat percentage above 30%) and normal weight with central obesity (normal BMI but visceral fat area above 80 cm2) show different degree of metabolic dysregulation. However, those population are usually overlooked in clinical practice and there is a paucity of research on those population and GDM.
To explore the correlation between body composition in early pregnancy and GDM in a population of normal pre-pregnancy BMI, and to investigate the relationship between fat distribution and GDM.
We performed a study that included 1 938 singleton pregnant women registered in the obstetric out-patient clinic of Beijing Obstetrics and Gynecology Hospital, Capital Medical University from October 2018 to October 2022. They voluntarily underwent nutritional assessment in early pregnancy and had regular pregnancy check-ups until 24-28 weeks of gestation, who underwent body composition testing in early pregnancy (6-16 weeks) and oral glucose tolerance test (OGTT) at 24-28 weeks. According to the OGTT results, the study population were divided into the GDM group (n=382) and the normal group (n=1 556). We estimated the relationship between body composition and fat distribution with GDM in early pregnancy with binary Logistic regression.
Body fat mass (BFM), visceral fat area (VFA), percentage body fat (PBF), and fat mass index (FMI) in the GDM group were higher than in the normal group (P<0.05). BFM, VFA, PBF, FMI (OR=1.044, 95%CI=1.012-1.078; OR=1.007, 95%CI=1.002-1.012; OR=1.041, 95%CI=1.012-1.070; OR=1.138, 95%CI=1.043-1.241) (P<0.05) and central obesity (VFA≥80 cm2) (OR=1.396, 95%CI=1.101-1.770, P<0.05) associated with a significant increased risk for GDM with binary Logistic regression analysis. Spearman rank correlation analysis showed that BFM, VFA, PBF, FMI and blood glucose of the OGTT test were positively correlated (P<0.05) .
Among normal pre-pregnancy BMI women, BFM, VFA, PBF, and FMI in early pregnancy were the risk factors of GDM. Central obesity (VFA≥ 80 cm2) could independently predict the development of GDM. It is necessary to pay attention to fat distribution during pregnancy check-ups and to strengthen the pregnancy management for central obesity women.
Given the increased risk of adverse pregnancy outcomes in pregnant women with type 2 diabetes, in addition to glycemic control, it is crucial to understand the relationship between gestational weight gain and adverse pregnancy outcomes.
To investigate the gestational weight gain in pregnant women with type 2 diabetes and its relationship with pregnancy outcomes.
A retrospective analysis was conducted on 691 cases of pregnant women with type 2 diabetes who underwent prenatal care and delivery at Beijing Obstetrics and Gynecology Hospital, Capital Medical University, from 2012 to 2020. According to the Chinese "Standard of Recommendation for Weight Gain during Pregnancy Period", the participants were categorized into the inadequate weight gain group (n=143), appropriate weight gain group (n=289), and excessive weight gain group (n=259). The gestational weight gain characteristics, maternal outcomes, and neonatal outcomes were compared among the three groups. Multivariate Logistic regression analysis was employed to explore the impact of gestational weight gain on pregnancy outcomes.
The results of multivariate Logistic regression analysis showed that compared to the appropriate weight gain group, the excessive weight gain group had increased risks of cesarean section (aOR=1.626, 95%CI=1.110-2.382), preeclampsia (aOR=1.997, 95%CI=1.071-3.677), macrosomia (aOR=1.948, 95%CI=1.175-3.230), and large for gestational age (LGA) (aOR=2.090, 95%CI=1.321-3.306), while reducing the rate of vaginal delivery (aOR=0.617, 95%CI=0.415-0.918). The inadequate weight gain group was associated with a reduced risk of delivering LGA (aOR=0.497, 95%CI=0.255-0.970), with no impact on small for gestational age (SGA) (P>0.05). Further stratified analysis revealed that excessive weight gain group with pre-pregnancy BMI≥24.0 kg/m2 increased the risks of cesarean section, preeclampsia, LGA [aOR and 95%CI were 1.673 (1.082-2.587), 1.961 (1.022-3.761), 2.031 (1.221-3.379), respectively], while reducing the rate of vaginal delivery (aOR=0.589, 95%CI=0.372-0.933). The inadequate weight gain group with pre-pregnancy BMI≥24.0 kg/m2 showed a decreased risk of delivering LGA (aOR=0.487, 95%CI=0.237-0.999). Excessive weight gain during early, middle, and late pregnancy was identified as a risk factor for macrosomia [aOR and 95%CI were 1.07 (1.00-1.15), 1.16 (1.03-1.31), and 1.16 (1.06-1.27), respectively] and LGA [aOR and 95%CI were 1.08 (1.01-1.16), 1.13 (1.02-1.26), and 1.16 (1.07-1.26), respectively]. Excessive weight gain during late pregnancy was associated with gestational hypertension and preeclampsia (aOR=1.13, 95%CI=1.02-1.24; aOR=1.14, 95%CI=1.03-1.26), while excessive weight gain during middle and late pregnancy was a risk factor for cesarean section (aOR=1.11, 95%CI=1.02-1.21; aOR=1.09, 95%CI=1.02-1.17) .
Excessive gestational weight gain increases the risk of adverse pregnancy outcomes such as LGA, macrosomia, preeclampsia, and cesarean section in women with type 2 diabetes during pregnancy. Inadequate gestational weight gain reduces the risk of LGA, but does not increase the risk of SGA. There is a clear correlation between gestational weight gain during different stages of pregnancy and adverse pregnancy outcomes. Therefore, optimizing blood glucose levels during pregnancy in patients with type 2 diabetes should be accompanied by enhanced education and interventions on weight gain management from preconception and early pregnancy stages.
