不明原因习惯性流产患者蜕膜自然杀伤细胞活性及表型的研究

目的 :探讨原因不明习惯性流产 (UHA)患者蜕膜自然杀伤 (NK)细胞的数量、表型特征及杀伤活性 ,探讨其在UHA发病中的作用。方法 :选取确定妊娠并难免流产的UHA 32例 ,选取 2 0例正常妊娠行人工流产者作为对照组 ,用流式细胞仪检测两组蜕膜组织中NK细胞数量及表型 ,用改进的乳酸脱氢酶释放法测定NK细胞杀伤活性。结果 :正常早孕蜕膜中CD5 6+CD3- NK细胞占蜕膜单个核细胞的 60 .73± 13.2 4 % ,为蜕膜组织的优势细胞群 ,UHA患者蜕膜中CD5 6+CD3- NK细胞总量与正常妊娠蜕膜组织中相同 ,而其CD5 6+CD16- 亚群却明显低于正常妊娠组 (P <0 .0 5 ) ,CD5 6+CD16+亚群含量及CD5 6+CD16+/CD5 6+CD16- 比值均异常增高 (P均 <0 .0 5 )。UHA组蜕膜组织中NK细胞杀伤活性及其异常增高率均高于正常妊娠组 ,差异均有显著性 (P均 <0 .0 5 )。结论 :NK细胞是孕早期蜕膜组织中的优势细胞群 ,其亚群失衡及功能异常可导致自然流产     

细胞凋亡和PCNA在早孕绒毛滋养细胞及蜕膜中的表达与自然流产的关系

目的 :研究细胞凋亡与细胞增殖在早孕绒毛滋养细胞和蜕膜中的表达及与自然流产的关系。方法 :对孕 3月内 2 0例正常妊娠、2 0例第 1次自然流产 (SA)和 15例反复自然流产 (RSA)的绒毛和蜕膜组织应用TdT介导的dUTP缺口原位末端标记技术(TUNEL)检测细胞凋亡 ,应用免疫组织化学SP法检测增殖细胞核抗原 (PCNA)。结果 :正常早孕绒毛细胞滋养细胞、合体滋养细胞和蜕膜中的凋亡指数分别为 7.2 1± 1.2 4、8.89±2 .5 2和 7.70± 0 .82 ;SA组为 15 .4 0± 6 .5 9、2 5 .83± 6 .83和 32 .0 3± 3.2 7;RSA组为 18.77±8.2 2、34.0 2± 13.4 9和 34.96± 5 .4 6。增殖指数在正常早孕绒毛细胞滋养细胞、合体滋养细胞和蜕膜中为 6 4 .13± 5 .90、0和 6 2 .0 8± 4 .76 ;SA组为 6 7.0 2± 6 .79、36 .13± 3.5 6和 6 4 .94± 4 .6 0 ;RSA组为 6 8.6 7± 8.4 5、33.6 7± 4 .0 8和 6 3.99± 5 .5 4。即孕 3月内正常妊娠的绒毛和蜕膜组织中均有一定量的细胞凋亡与细胞增殖存在。SA与正常早孕相比绒毛和蜕膜中的细胞凋亡均明显增加 (P <0 .0 1) ,RSA合体滋养细胞凋亡也较SA明显增加 (P <0 .0 5 ) ;细胞滋养细胞和蜕膜中的细胞增殖在自然流产与正常妊娠间无明显差异 (P >0 .0 5 )。结论 :细胞凋亡和增殖的平衡与妊娠维持?     

不明原因早期复发性流产患者蜕膜自然杀伤细胞对滋养层细胞系侵袭功能的影响

目的研究早孕期复发性流产(RSA)患者与正常早孕妇女的蜕膜自然杀伤细胞(d NK)对滋养层细胞系HTR-8/SVneo侵袭能力的影响。方法收集正常早孕人工流产妇女(正常早孕组,n=10)和不明原因RSA患者(RSA组,n=8)的早孕蜕膜组织,用密度梯度离心法分离出蜕膜淋巴细胞,免疫磁珠法进一步分选出CD56+CD16-NK细胞,即蜕膜NK细胞,将蜕膜NK细胞与HTR-8/SVneo共培养24 h后,通过MTT法和Transwell侵袭实验检测蜕膜NK细胞对滋养层细胞系HTR8/SVneo黏附及侵袭能力的影响,用Real-time PCR检测共培养后HTR-8/SVneo细胞的MMP-2和MMP-9 mRNA水平的表达情况。结果与正常早孕妇女相比,不明原因早孕期RSA患者的蜕膜NK细胞对滋养层细胞系HTR8/SVneo侵袭能力有减弱作用,并使HTR-8/SVneo表达促侵袭分子MMP-2和MMP-9表达降低。结论妊娠早期局部母-胎界面d NK细胞的功能异常可能是导致不明原因RSA的一个原因。     

白血病抑制因子在早期妊娠、先兆流产及难免流产患者蜕膜组织中表达的研究

目的探讨白血病抑制因子(LIF)在蜕膜组织中的表达,及其与早期妊娠、流产的关系. 方法采用放射免疫方法检测正常早孕妇女(正常早孕组)、先兆流产妇女(先兆流产组)及难免流产妇女(难免流产组)的血清孕酮及人绒毛膜促性腺激素(hCG)水平,并采用逆转录-聚合酶链反应(RT-PCR)技术对3组孕妇蜕膜组织中LIF-mRNA的表达进行定量分析.结果 (1)孕酮及hCG水平在3组孕妇间的比较正常早孕组孕妇血清中孕酮、hCG水平分别为(91.5±27.2) nmol/L、(69.9±14.9) kU/L,先兆流产组孕妇分别为(88.4±24.7) nmol/L、(57.6±11.2) kU/L,两组孕妇血清孕酮、hCG水平比较,差异均无显著性(P>0.05);而难免流产组孕妇血清孕酮、hCG水平分别为(33.1±19.6) nmol/L、(10.3±3.2) kU/L,与前两组分别两两比较,差异均有极显著性(P<0.01).(2)LIF-mRNA平均相对含量在3组孕妇间的比较正常早孕组孕妇为2.10±0.32;先兆流产组孕妇为1.92±0.20;难免流产组孕妇为0.70±0.06.正常早孕组与先兆流产组比较,差异无显著性(P>0.05).而难免流产组与前两组分别行两两比较,差异均有显著性(P<0.05).结论 LIF-mRNA在早期妊娠蜕膜组织中的表达量降低,可能是导致hCG及孕酮分泌下降,最终造成难免流产的原因之一.     

米非司酮抗早孕蜕膜碱性成纤维细胞生长因子变化的研究

目的 :了解米非司酮对人早孕蜕膜碱性成纤维细胞生长因子 (basic fibroblast growthfactor,b FGF )的影响 ,探讨药物流产后子宫出血时间长的可能机理。方法 :取正常、服米非司酮、服米非司酮配伍米索前列醇 (米索 )后的早孕蜕膜各 1 5、1 5和 1 6例 ,应用酶联免疫吸附分析法定量测定蜕膜匀浆中 b FGF的水平 ;同时观察子宫出血的持续时间。结果 :正常早孕蜕膜匀浆中 b FGF水平为 2 6 8.81± 75.34pg/ mg蛋白 ;服米非司酮及服米非司酮配伍米索后蜕膜匀浆中 b FGF水平分别为 373.99± 45.94pg/ mg蛋白和 375.6 8±1 0 9.34pg/ mg蛋白。后两者间差异无显著性 (P>0 .0 5) ,但均较正常早孕蜕膜组升高 ,差异有显著性 (P均 <0 .0 1 )。子宫出血持续时间与正常早孕蜕膜组 (7.47± 1 .92 d)比 ,服米非司酮 (1 1 .38± 2 .2 5d)及米非司酮配伍米索组 (1 2 .73± 2 .2 2 d)均延长 ,差异有极显著性 (P均 <0 .0 0 1 ) ,后两者间差异无显著性 (P>0 .0 5)。结论 :米非司酮可使早孕蜕膜b FGF水平升高 ,停用米非司酮可引起子宫出血时间延长 ,药物流产后继续服用米非司酮可望缩短子宫出血时间     

正常妊娠中细胞增殖细胞凋亡情况的研究

目的　研究细胞增殖和细胞凋亡在正常妊娠不同孕期胎盘绒毛、蜕膜生长发育中的作用。方法　对 40例正常早孕吸宫流产病例和 40例正常晚孕分娩病例的胎盘绒毛和蜕膜进行分析 :免疫组织化学链霉菌抗生物素蛋白 -过氧化物酶法 (S -P法 )检测细胞增殖 ;用DNA缺口原位末端标记技术 (TUNEL法 )检测细胞凋亡。结果　正常早孕绒毛细胞滋养细胞、合体滋养细胞、蜕膜中的增殖指数 (PI)分别为 (70 74± 1 34 ) %、0、(89 32± 1 75 ) % ,凋亡指数 (AI)分别为 (10 2 7± 0 35 ) %、(15 2 8± 2 43) %、(5 2 3± 1 35 ) %。正常晚孕胎盘细胞滋养细胞、合体滋养细胞和蜕膜中增殖指数 (PI)分别为 (2 10± 1 2 8) %、0、(2 0 4± 1 31) % ;凋亡指数 (AI)分别是 (1 0 6± 0 94) %、(41 79±1 48) %、(6 0 81± 1 41) %。即 :正常早、晚孕绒毛和蜕膜组织中都有一定量的细胞增殖和细胞凋亡发生 ,但早孕时以细胞增殖为主 (P <0 0 1) ,晚孕时以细胞凋亡为主 (P <0 0 1)。结论　细胞增殖和细胞凋亡都是细胞生长代谢的形式 ,随着妊娠进展 ,胎盘细胞增殖下降、细胞凋亡增加。提示 :细胞增殖和凋亡对胎盘绒毛的正常发育和老化起重要作用     

妊娠肝内胆汁淤积症患者胎盘细胞凋亡及调控基因的研究

目的　通过观察妊娠肝内胆汁淤积症 (ICP)患者胎盘细胞凋亡调控基因p5 3、bax和bcl 2在胎盘中的表达 ,探讨细胞凋亡基因在胎盘细胞凋亡中的作用。方法　采用原位末端标记法(TUNEL)和免疫组织化学方法对 3 1例ICP患者 (ICP组 )的胎盘组织中p5 3、bax和bcl 2基因表达及调亡指数进行检测 ,并以 3 1例正常妊娠妇女的胎盘组织作对照 (对照组 )。结果　 (1)ICP组胎盘组织中细胞滋养细胞、合体滋养细胞、蜕膜细胞及间质细胞中细胞凋亡指数分别为 (49 1± 9 1) %、(46 6±9 8) %、(3 5 1± 9 5 ) %、(3 8 7± 9 7) % ,明显高于对照组的 (2 2 5± 6 2 ) %、(2 1 6± 5 2 ) %、(17 9±6 2 ) %、(17 0± 4 7) %。两组比较 ,差异有极显著性 (P <0 0 1)。 (2 )而调控基因p5 3的表达 ,ICP组明显高于对照组 ,两组比较 ,差异有极显著性 (P <0 0 1) ;bax的表达在两组滋养细胞中比较 ,差异无显著性 (P >0 0 5 )。但在合体滋养细胞、蜕膜细胞及间质细胞中 ,ICP组明显高于对照组 ,两组比较 ,差异有极显著性 (P <0 0 1) ;bcl 2的表达在ICP组胎盘组织细胞滋养细胞、合体滋养细胞、蜕膜细胞及间质细胞中 ,均明显低于对照组 (P <0 0 1)。 (3 )p5 3、bax和bcl 2在ICP组合体滋养细胞中的表达分别是 (75 9± 8 2 ) %、(65     

妊高征孕妇血清β-HCG及HPL水平测定

目的 :探讨血清 β绒毛膜促性腺激素 (β HCG)及胎盘泌乳素 (HPL)水平与妊娠高血压综合征 (妊高征 )之间的关系。方法 :用放射免疫法测定 1 1 8例正常妊娠妇女及 42例妊高征妇女血清 β HCG及HPL水平。结果 :正常妊娠妇女血清 β HCG为 1 2 .0 4± 5.62 μg/L ,妊高征妇女血清 β HCG为 2 2 .32± 9.40 μg/L,两组比较差异有显著性 (P <0 .0 5)。β HCG水平与妊高征病情严重程度呈正相关 (γ=0 .56P <0 .0 5) ;正常妊娠妇女血清HPL为 6.1 8± 3 .2 7mg/L ,妊高征妇女为 6 .35± 2 .79mg/L ,妊高征组与正常妊娠妇女组比较 ,差异无显著性 (P >0 .0 5)。结论 :β HCG可反映妊高征时胎盘滋养细胞功能紊乱程度及病情的严重程度     

NK细胞与不明原因早期自然流产的临床研究

目的:探讨NK细胞与不明原因早期自然流产的关系.方法:采用流式细胞仪与免疫荧光技术,检测不明原因早期自然流产患者(病例组)和正常妊娠早期妇女(早孕组)外周血及蜕膜组织中NK细胞的百分含量.结果:病例组外周静脉血中NK细胞百分含量和早孕组相比,差异有高度统计学意义(P<0.01),病例组蜕膜中NK细胞百分含量和早孕组蜕膜中NK细胞百分含量相比,差异有高度统计学意义(P<0.01).结论:不明原因早期自然流产患者静脉血及蜕膜组织中NK细胞的含量均低于正常妊娠早期妇女外周静脉血及蜕膜组织中NK细胞的含量.     

白血病抑制因子在正常早孕、先兆流产及难免流产患者绒毛组织中的表达

目的测定白血病抑制因子(LIF)在正常早孕、先兆流产及难免流产患者绒毛组织中表达的差异,探讨LIF在先兆流产及难免流产发病中的作用。方法采用放射免疫法检测正常早孕妇女(正常早孕组,30例)、先兆流产患者(先兆流产组,30例)及难免流产患者(难免流产组,30例)血清孕酮及人绒毛膜促性腺激素(hCG)水平;采用免疫组化技术———链霉菌抗生物素蛋白-过氧化酶连接(SP)法对LIF在3组妇女绒毛组织中的表达进行组织学定位和半定量分析;采用蛋白印迹法对3组妇女绒毛组织中LIF的相对表达量进行测定。结果(1)血清孕酮及hCG水平在正常早孕组、先兆流产组及难免流产组分别为(95±26)、(90±26)、(36±17)nmol/L及(75±14)、(68±13)、(13±3)kU/L。正常早孕组与先兆流产组血清孕酮及hCG水平分别比较,差异均无统计学意义(P>0·05);而难免流产组与其他两组妇女血清孕酮及hCG水平分别比较,差异均有统计学意义(P<0·01)。(2)3组妇女绒毛组织中LIF均呈现阳性表达,阳性染色主要位于滋养细胞胞质中,胞核无明显着色。(3)正常早孕组、先兆流产组及难免流产组LIF相对表达量分别为1·17±0·13、1·06±0·10、0·30±0·02,难免流产组与其他两组分别比较,差异均有统计学意义(P<0·01),而正常早孕组与先兆流产组比较,差异无统计学意义(P>0·05)。结论LIF对妊娠的正常维持有一定的保护作用,LIF在早孕绒毛组织中的低表达,可能与hCG及孕酮水平下降有关,是导致难免流产的原因之一。     

妊娠肝内胆汁淤积症患者的胎儿淋巴细胞研究

目的探讨胎儿淋巴细胞在妊娠肝内胆汁淤积症(ICP)发病中的作用。方法采用单向混合淋巴细胞反应法,检测20例ICP患者(ICP组)及20例正常孕妇(对照组)的脐血胎儿淋巴细胞与母体外周血已灭活的淋巴细胞、皮肤组织可溶性抗原、蜕膜组织可溶性抗原的增殖反应情况。结果(1)ICP组脐血胎儿淋巴细胞与母体已灭活的淋巴细胞混合反应中,胎儿淋巴细胞的增殖反应程度为2．75±0．36,显著高于对照组的1．45±0．19,两组比较,差异有统计学意义(P＜0．05);(2) ICP组脐血胎儿淋巴细胞与母体蜕膜组织可溶性抗原混合反应中,胎儿淋巴细胞的增殖反应程度为1．45±0．19,显著高于对照组的0．67±0．24,两组比较,差异有统计学意义(P＜0．05);(3)ICP组脐血胎儿淋巴细胞与母体皮肤组织可溶性抗原反应中,胎儿淋巴细胞的增殖反应程度为1．22±0．44,显著高于对照组的0．66±0．27,两组比较,差异有统计学意义(P＜0．05)。结论胎儿淋巴细胞可能是ICP发病过程中的主要效应细胞之一;母-胎间免疫失衡是ICP发病的重要机制之一。     

Immunomodulating properties of sera in normal pregnant women]

The purpose of this study was to analyze the immunosuppressive properties of sera of normal pregnant women. Effects of pregnancy sera on the proliferation of mitogen (PHA, Con A, PWM)-induced lymphocytes were examined in healthy primiparas. The sera of normal pregnant women inhibited the proliferation of PHA- and Con A- induced both autologous and allogenic lymphocytes (obtained from nonpregnant and pre-eclamptic women), while remaining neutral towards the proliferation of PWM- induced lymphocytes in comparison with fetal calf serum. The basic immunomodulatory activity of the sera in pregnant women was contained in the heat-stable fraction.     

Study on the activity and phenotype of decidual natural killer cells in patients with unexplained habitual abortions

Habitualabortionsoccurin 1to 2 %ofthechild bearingpopulation .Chromosomalaberrationistheprincipalcauseoffetallossduringtheearlystageofgestation .Oth eretiologies ,whichincludeanatomicanomalies ,endocrinedisorders,andinfections ,havealsobeendocumemtedinpatientswithhabitualabortions .Nevertheless ,in 4 0to6 0 %ofcouples ,habitualabortionsremainunexplained ,whicharecalledUHA .Recently ,theimportanceofim munologyinUHAisrecognized .Immunecellsareabun dantinhumandeciduaandarecapableofrespondingto…     

The distribution of CA 125 in the reproductive tract of pregnant and non-pregnant women

Summary. Investigation of serum and tissue homogenates obtained from first, second and third trimester pregnancies, and from nonpregnant women, has provided further insight into the possible origin of the CA 125 antigen. Serum CA 125 levels were higher in the first trimester (median 53.6 U/ml, range 15.6.268.3 U/ml) than in nonpregnant women (median 19.3 U/ml, range 7.2.27.0 U/ml) and later in pregnancy (second trimester: median 18.5 U/ml, range 12.0.25.1 U/ml, third trimester: median 19.2 U/ml, range 16.8.43.8 U/ml) (P<0.05) but were two orders of magnitude less than in second trimester amniotic fluid (median 4825 U/ml, range 3200.9300 U/ml). Fetal serum CA 125 activity was consistently <20 U/ml. The highest tissue levels of CA 125 were detected in first trimester decidual homogenate (median 4547 U/ 100 mg, range 340.4–20 851 U/100 mg) and were greater than in nonpregnant endometrium (median 388 U/100 mg, range 100.9–3341 U/100 mg) ( P <0.01) and term decidua (median 116 U/100 mg, range 32.7–449.9 U/100 mg) (P<0.01). These observations suggest that CA 125 is synthesized by normal endometrium and decidua and that increased CA 125 activity during pregnancy is of decidual origin.     

Serum adenosine deaminase activity and its isoenzyme pattern in women with normal pregnancies

Adenosine deaminase (ADA) is a purine enzyme which is essential for the proliferation, maturation and function of lymphoid cells, and congenital deficiency of this enzyme is associated with severe combined immunodeficiency disease. The activity of ADA has changed in diseases characterized by the alteration of cell-mediated immunity such as rheumatoid arthritis, systemic lupus erythematosus and tuberculosis, so ADA has been considered as a nonspecific marker of cell-mediated immunity. In this study we examined changes in serum total ADA activity and the patterns of two ADA isoenzymes, ADA1 and ADA2 in normal pregnant women, and evaluated the possible role of the alteration of cell-mediated immunity during normal pregnancy as causes of changes in ADA activity. We measured serum activities of total ADA, ADA1 and ADA2 in normal pregnant women in the third trimester (n=24) and age-matched healthy nonpregnant women (n=24). Peripheral blood lymphocytes and monocytes were also measured. In normal pregnant women, serum total ADA activity averaged 10.5 +/- 0.5 U/L, which was significantly lower than in nonpregnant women (14.0 +/- 0.5 U/L ) (p<0.05), and mean serum ADA2 activity also significantly reduced that of nonpregnant women (p<0.05). There was no significant difference in ADA1 activity in normal pregnant and nonpregnant women. The decrease in total ADA activity was accompanied by the decrease in lymphocyte count. These results suggest that reduced serum total ADA activity reflects decrease in ADA2 activity, and which may be in part associated with depressed cell-mediated immunity during normal pregnancy.     

Human NK cell activity is not inhibited by pregnancy and cord serum factors and female steroid hormones in vitro

The effects of female sex steroid hormones and of pregnancy and cord sera on human NK cell activity against the NK sensitive K562 cells were studied. The cytotoxicity of adult peripheral blood lymphocytes was measured after incubation of peripheral blood effector cells in vitro with estrone, 17 beta-estradiol, estriol, or progesterone at concentrations ranging from 1 to 1000 nM. The cytotoxic activity of effector cells was not altered by pre-treatment of cells with steroid hormones, and the presence of the steroids in the NK assays caused minor changes only at the highest concentrations. Similarly, the effects of sera obtained from pregnant women during the third trimester and from cord blood were studied. Compared to normal pooled AB serum, pregnancy and cord sera had no effect on NK cell activity. On the contrary, the presence of fetal calf serum in the culture medium consistently resulted in a higher NK activity than that obtained with AB serum, cord serum, pregnancy serum, or the medium alone. The augmenting effect of human leukocyte interferon on NK cell activity was not inhibited by these sera. It is concluded that female sex steroid hormones and pregnancy and cord sera are not inhibitory in vitro to normal human NK cells.     

Increased maternal serum 3 alpha, 17 beta-androstanediol glucuronide concentrations during pregnancy

Maternal serum concentrations of 3 alpha, 17 beta-androstanediol glucuronide (3 alpha-diol-G), a substance that reflects peripheral androgen action and tissue 5 alpha-reductase activity, were measured in 33 normal men, 51 nonpregnant women, and 51 women with uncomplicated pregnancies. The 3 alpha-diol-G concentrations in men (median, 201 ng/ml) were significantly higher than in nonpregnant women (median, 42 ng/ml) or pregnant women (median, 124 ng/ml). The concentrations in pregnant women were significantly greater than those in nonpregnant women, and there were no significant differences between trimesters in maternal 3 alpha-diol-G concentrations. There were no fetal sex differences found in maternal serum or in third-trimester amniotic fluid. These results indicate that pregnancy is associated with increased androgen production by maternal tissues and that fetal 3 alpha-diol-G production is low.     

Cytokine production in natural killer cells and lymphocytes in pregnant women compared with women in the follicular phase of the ovarian cycle

OBJECTIVE: To test whether peripheral natural killer (NK) cells, helper T cells, and cytotoxic lymphocytes of pregnant women shift from a type 1 cytokine production toward a type 2 cytokine production as compared with these cells in women in the follicular phase. DESIGN: Prospective study. SETTING: Outpatient clinic. PATIENT(S): Healthy nullipara at 30 weeks' amenorrhea and healthy nonpregnant women in their follicular phase. INTERVENTION(S): Samples of whole blood were stimulated with phorbol myristate acetate (PMA; Sigma Chemical Co., St. Louis, MO) and Ca-ionophore in the presence of monensin (Sigma). Lymphocytes were stained with alpha-CD3, alpha-CD8, and alpha-interferon gamma (IFN-gamma) alpha-interleukin 2 (IL-2), IL-4, or IL-10. Analysis was performed by flow cytometry. Statistical evaluation was done with the Mann-Whitney U test. MAIN OUTCOME MEASURE(S): Percentage NK cells, helper lymphocytes, and cytotoxic lymphocytes that were producing IFN-gamma, IL-2, IL-4, or IL-10. RESULT(S): There is a statistically significant decrease in the percentage of NK cells, and helper and cytotoxic lymphocytes that produced IFN-gamma in pregnant women when compared with women in the follicular phase. There is also a statistically significant decrease in the percentage of helper lymphocytes producing IL-2 in pregnant women compared with nonpregnant women. CONCLUSION(S): We found a decrease in type 1 cytokine production with no change in type 2 cytokine production after in vitro stimulation of "pregnant" NK cells and lymphocytes as compared with "nonpregnant" NK cells and lymphocytes. We suggest that NK cell and lymphocyte response are shifted away from a type 1 immune response during pregnancy.     

Origin of raised maternal serum alpha-fetoprotein levels in second-trimester oligohydramnios.

Concanavalin A (Con A) subtyping of alpha-fetoprotein (AFP) revealed higher concentrations of AFP non-reactive with Con A in sera of 12 pregnant women with second-trimester oligohydramnios and raised total serum AFP levels than in sera of 42 pregnant women with raised total serum AFP levels and a normal amniotic fluid volume. This suggests that in oligohydramnios the origin of excess AFP in the maternal compartment is amniotic fluid. It is proposed that oligohydramnios and the associated raised maternal serum AFP levels are caused by damage of the fetal membranes prior to 16 weeks of gestation resulting in leakage of amniotic fluid to the decidual tissue and resorption in the maternal circulation.