目的 :研究孕妇宫内感染解脲支原体 (Uu)后对新生儿出生体重的影响。方法 :利用 PCR技术检测 46例足月新生儿胎盘组织、脐静脉血及咽吸出物中解脲支原体感染状况。结果 :Uu+的胎盘平均重量与 Uu-的胎盘平均重量相比差异显著 (P<0 .0 5)。胎盘 Uu+的足月新生儿平均出生体重较 Uu-的足月新生儿平均出生体重低 41 1 g,差异显著 (P<0 .0 5)。足月小样儿胎盘 Uu感染率为75% (3/4) ,而足月正常儿胎盘 Uu感染率为 2 1 .43% ,差异显著 (P=0 .0 4 9)。咽吸出物、脐血 Uu+的足月新生儿平均体重虽然较 Uu-组低 ,但无显著差异。结论 :宫内胎盘 Uu感染可致新生儿出生体重降低 Objective: To study the effect of intrauterine infection of Ureaplasma urealyticum (Uu) on the birth weight of pregnant women. Methods: The infection of Ureaplasma urealyticum in placenta tissue, umbilical cord blood and pharyngeal aspirates from 46 full-term neonates was detected by PCR. Results: The average placental weight of Uu + was significantly different from that of Uu- (P <0.05). The average birth weight of full-term newborns with placenta Uu + was 41 1 g lower than that of Uu-term full-term newborns with significant difference (P <0.05). The Uu infection rate was 75% (3/4) in term infants and 21.143% in term infants. The difference was significant (P = 0.049). Pharyngeal aspirates, umbilical cord blood Uu + full-term newborns, although the average body weight lower than the Uu-group, but no significant difference. Conclusion: Intrauterine placenta Uu infection can lead to birth weight loss in newborns