Pre-pregnancy obesity can have a range of effects on both the mother and the fetus, possibly due to abnormalities in maternal-fetal metabolism. Therefore, exploring the mechanisms is essential to improve fetal prognosis.

To investigate the alterations of factors associated with obesity and glucose metabolism in the placentas of pregnant women with different BMI levels before pregnancy.

A total of 100 singleton pregnant women who delivered in Beijing Shijitan Hospital, Capital Medical University in 2019 were selected as the study subjects. The clinical data were collected based on the electronic medical record system. The subjects were divided into the low/normal body mass group (n=57) and overweight/obese group (n=43) based on their pre-pregnancy body mass. The expression of long non-coding RNA metastasis-associated Lung adenocarcinoma transcript 1 (LncRNA MALAT1), serum amyloid A3 (SAA3), and interleukin 6 (IL-6) mRNA in placental tissue were measured using reverse transcription-polymerase chain reaction.

The age of the subjects ranged from 22 to 43 years, with an average age of (32.7±4.2) years, including 61 primiparas, 21 with gestational diabetes mellitus (GDM), 14 with low body mass, 43 with normal body mass, 26 with overweight, and 17 with obese. The proportion of GDM and neonatal body mass in the overweight/obese group was higher than that in the low/normal body mass group, and the weight gain during pregnancy was lower than that in the low/normal body mass group, with statistically significant differences (P<0.05). The expression of LncRNA MALAT1 mRNA in placental tissue was higher in the overweight/obese group than the low/normal body mass group, with a statistically significant difference (P<0.05). The mRNA expression of LncRNA MALAT1, SAA3, and IL-6 mRNA in the placental tissue of obese pregnant women were higher than those of normal pre-pregnancy body mass, with statistically significant difference (P<0.05) .

Excessive pre-pregnancy BMI has a more significant impact on mother and child during pregnancy, overshadowing the effects of controlling weight gain during pregnancy. In obese pregnant women, LncRNA MALAT1 may regulate glucose and lipid homeostasis through SAA3 and IL-6, involving inflammatory changes and oxidative stress, thereby affecting fetal metabolism, which deserves more in-depth exploration.

孕前肥胖会给母体及胎儿带来一系列影响，其机制可能与母胎代谢异常有关，因此，探讨其机制对于改善胎儿预后至关重要。

探讨孕前不同BMI孕妇胎盘中与肥胖及血糖代谢相关因子的改变。

选取2019年在首都医科大学附属北京世纪坛医院分娩的单胎孕妇100例为研究对象，通过电子病历系统收集研究对象的临床资料，将孕妇按体质量分为孕前低体质量/正常体质量组（57例）和孕前超重/肥胖组（43例）。采用反转录-聚合酶链反应检测孕妇胎盘组织长链非编码RNA肺腺癌转移相关转录本1（LncRNA MALAT1）、血液淀粉样抗原3（SAA3）、白介素6（IL-6）mRNA表达。

研究对象年龄22~43岁，平均年龄（32.7±4.2）岁；其中初产妇61例，妊娠期糖尿病（GDM）患者21例，低体质量14例，正常体质量43例，超重26例，肥胖17例。孕前超重/肥胖组GDM比例、新生儿体质量高于孕前低体质量/正常体质量组，妊娠期增重低于孕前低体质量/正常体质量组（P<0.05）。孕前超重/肥胖组孕妇胎盘组织LncRNA MALAT1 mRNA表达量高于孕前低体质量/正常体质量组（P<0.05）。孕前肥胖孕妇胎盘组织中LncRNA MALAT1、SAA3、IL-6的mRNA表达量高于孕前正常体质量孕妇（P<0.05）。

孕前过高的BMI对妊娠期母婴的影响更大，掩盖了妊娠期控制体质量增加的效果。在肥胖孕妇中，LncRNA MALAT1可能通过SAA3、IL-6调节葡萄糖和脂肪稳态，涉及炎症变化和氧化应激，从而影响胎儿代谢，值得进行更深入的探索。