• 作者： 陳瑞堅; 朱健次
• 作者服務機構： 國立臺灣大學醫學院婦產科; 國立臺灣大學醫學院細菌科
• 中文摘要： 妊娠末期母體血清人類絨毛膜性腺激素(human chorionic gonadotropin,hCG)濃度有上升之趨勢。有些人認為這是由於懷女嬰者到妊娠末期hCG濃度升高所致。但有關胎兒性別會不會造成懷孕末期母血hCG濃度值之差異，仍有不同的看法；臍帶血方面亦然。而且，所有臍帶血的研究在過去都是採取臍帶動脈與臍帶靜脈之混合血。然而在實際上，臍帶動脈與靜脈hCG濃度是否相同，以及是否還會受到胎兒性別的影響，仍是一個問題。還有，胎兒性別是否會對hCG在胎盤障壁之傳遞造成影響，也未有所知。因此本研究希望對此些問題有所澄清。 總共以188名妊娠末期（36－42週），無妊娠併發症，而且正常分娩之產婦為研究對象。同時抽取母，臍帶靜、動脈血。以Sb3多源抗體作放射免疫分析。這些產婦之年齡、胎次，以生男、女嬰來分時，並無不同。男嬰與女嬰之體重也無異。血清hCG值變化很大（200－75，200mIU/ml）；其幾何平均數，在懷女嬰者（11，500mIU/ml）高於懷男嬰者（6,470mIU/ml）（P<0.001）。女嬰之臍帶靜脈血hCG濃度（幾何平均數為26.8mIU/ml）也高於男嬰之臍帶靜脈血（幾何平均數19.5mIU/ml）（p<0.01）。 於54配對臍帶動脈與臍帶靜脈血中，臍帶動脈血hCG濃度（幾何平均數10.05mIU/ml）與臍帶靜脈血者（10.92mIU/ml）兩者無差異（p>0.05，paired t-test）。此54對臍帶動、靜脈血中各有27對為得自生產時之男、女嬰臍帶。為除去胎兒性別的影響，將此資料作重覆二因子變異數分析，結果得知不論是男嬰或女嬰，臍帶動靜脈血hCG濃度均一樣高。男、女嬰之臍帶動脈血hCG值與臍帶靜脈血之值，女嬰均比男嬰高。 另外，針對這126名臍帶靜脈血hCG值與母血hCG濃度間之關係，是否也受性別的影響，也作線性迴歸與相關，以及共變數分析。結果顯示不管是男或女嬰，其臍帶靜hCG濃度均與母血hCG值成密切關係（p<0.05），而且其關係也不受胎兒性別的影響。 此研究顯示胎盤之產生hCG是受到胎兒性別的影響。妊娠末期，如果是女嬰，母血及其胎兒臍帶動、靜脈血中hCG濃度均比較高，可能是懷女嬰時，胎盤較易產生hCG。另外，不管胎兒性別為何，臍帶動、靜脈血中hCG濃度均相同。而且，母血與胎兒臍血hCG濃度之比值也不受胎兒性別的影響。此結果暗示：胎兒性別可能在懷孕末期胎盤之生成hCG具有調節作用；在胎兒與胎盤單位中，胎兒本身並不參與生成或消耗hCG，而且此點並未受到胎兒性別的影響；另外，胎兒性別也不會對hCG在胎盤障壁之傳遞造成影響。
• 英文摘要： There were discordant results regarding the effect of fetal sex on hur m chorionic gonadotropin(hCG) concentrations in maternal or fetal circulation and regarding whether the levels in umbilical arteriesare equal to those in umbilical veins. Totally, 188 singleton pregnancies at 36 to 42 weeks of gestationwithout any obstetrical or medical complication were studied. The hCG levels were measured by radioim-munoassay specific for hCG using Sb3 antibody raised against beta-subunit of hCG. The maternal ages andparities between those who gave birth to a male or a female baby were not different statistically. The birthweights between male and female babies were also not different. The serum hCG levels had a wide range in maternal circulation (200-75,200 mIU/m1) and theirdistribution was positively skewed. The mean value (geometric mean, G.M.) in maternal circulation forthose who carried a female fetus (11,500 mIU/m1) was significantly higher than that for those carrying amale fetus (6,470 mIU/m1) (P<0.001, Student's t-test). The hCG concentrations in umbilical veins offemale fetuses were also higher than in those of male fetuses (G.M., 26.8 vs 19.5 mIU/m1, P<0.01, Stu-dent's t-test). Umbilical arterial hCG levels (G.M., 10.05 mIU/m1) were statistically not different fromumbilical venous levels (G,M., 10.92 mIU/ml) (paired t-test). Two-way ANOVA analysis with repeatedmeasure for paired data showed that there was no interaction between the factor of fetal sex and the factorof concentrations correlated well with umbilical venous hCG levels in female bearers (γ=0.724，P<0.001)as well as in male bearers (γ=0.762, P<0.001). By analysis of covariance, fetal sex was revealed to haveno effect on the relationship between maternal and umbilical hCG levels. These results revealed that hCG levels in maternal circulation in late pregnancy were higher inmothers with female fetuses than in those with male fetuses. Umbilical hCG levels were also higher infemale fetuses than in male. Umbilical arterial hCG levels were statistically not different from the levelsin umbilical veins, and fetal sex had no effect on the hCG levels in umbilical arteries or veins. In addition,hCG levels in maternal or fetal circulation correlated well and were not affected by fetal sex. These resultsimplied that：in the feto-placental unit, fetal sex might modulate the placental production of hCG; thefetus per se might not consume hCG; and fetal sex might not influence hCG transport through the placentalbarrier.
• 中文關鍵字： hCG; fetal sex; umbilical artery and vein
• 英文關鍵字： --