First trimester maternal serum ischaemia-modified albumin: a marker of hypoxia-ischaemia-driven early trophoblast development

BACKGROUND: A hypoxic intrauterine environment is believed to play a pivotal role in physiological trophoblast development. Ischaemia-modified albumin (IMA) is used in the measurement of cardiac ischaemia. We aimed to test the hypothesis that maternal serum IMA may be elevated in early pregnancy as a measurable manifestation of intrauterine ischaemia. METHODS: Prospective observational study in healthy women with singleton pregnancies (n=66) and non-pregnant controls (n=26). Maternal serum IMA levels were measured at 11-13 weeks of gestation and in non-pregnant women. RESULTS: The median IMA level in the pregnant group [115.14 kU/l; interquartile range (IQR) 102.33-124.71 kU/l] was significantly higher (P<0.001) than in non-pregnant controls (73.71 kU/l; IQR 60.38-82.78 kU/l). During pregnancy, absolute values of IMA were higher than the concentration used for the diagnosis of myocardial ischaemia (>95 kU/l) in 86% of women. CONCLUSIONS: In early pregnancy, IMA levels were above the concentration used for the diagnosis of myocardial ischaemia in most women, and should therefore not be used as a marker for cardiac ischaemia in pregnancy. Maternal serum IMA is elevated to supra-physiological levels in early normal pregnancy supporting the hypothesis that normal trophoblast development is associated with a hypoxic intrauterine environment, although other mechanisms leading to an IMA increase cannot be excluded.     

Effect of first-trimester serum from pregnant women with high-resistance uterine artery Doppler resistance on extravillous trophoblast invasion

BACKGROUND: Abnormal uterine artery Doppler indices are associated with pregnancy complications such as pre-eclampsia and intrauterine growth restriction. Poor trophoblast invasion may be a consequence of, or be associated with, abnormal Doppler indices. OBJECTIVE: To evaluate in vitro trophoblast function following exposure to first-trimester serum from pregnancies with high uterine artery Doppler resistance indices. METHODS: Doppler ultrasound examination of the maternal uterine arteries was performed on women at 10-14 weeks' gestation. Serum was collected from women with bilateral uterine artery notches with resistance indices above the 95th centile and from patients with normal uterine artery indices. The effect of serum on trophoblast invasion was determined using an established in vitro model from the extravillous trophoblast-derived cell line SGHPL-4. RESULTS: Trophoblastic invasion was significantly reduced when treated with serum from women with high-resistance compared with normal-resistance uterine artery Doppler indices (P < 0.05). CONCLUSION: Maternal serum in the first trimester of pregnancy from patients with high-resistance uterine artery Doppler indices appears to inhibit trophoblast invasion. This experimental model allows further investigation of factors responsible and the evaluation of therapeutic strategies.     

Activation of the novel prothrombinase, fg12, as a basis for the pregnancy complications spontaneous abortion and pre-eclampsia

PROBLEM: Impaired trophoblast invasion during the first trimester of pregnancy is linked to spontaneous abortion, and defective invasion in the second trimester to hypertension + proteinuria (pre-eclampsia). Hypertension developing during the third trimester of human pregnancy represents, in part, a corrective response in the mother to provide adequate placental perfusion for fetal growth when trophoblast has not to invaded and converted the myometrial porprtion of maternal spiral arteries into to low resistance-high capacitance conduits. Deportation of vesicles from hypoxemic trophoblast is thought to cause hypertension plus proteinuria, vascular damage and a systemic coagulopathy. Trophoblast invasion may be inhibited by local cytokines, such as TGF-betas but Thl-type cytokines associated with pre-eclapmsia and spontaneous abortions (e.g., IL-1, TNF-alpha, IFN-gamma) are not known to inhibit migration at in situ concentrations. Trophoblast invasion is also inhibited by the binding of surface integrins to fibronectin and fibrin, and fibrin production is stimulated by these Th1 cytokines via up-regulation of prothrombinases(s) such as fg12 which directly and via TNF-alpha-facilitated inflamation compromise trophoblast cell integrity. We, therefore, asked if fg12 expression and TNF-alpha are increased in first trimester human miscarriage and in third trimester pre-eclampsia. METHODS: fg12 mRNA was detected using in situ hybridization and fg12 protein by immunohistochemistry. TNF-alpha mRNA and protein were similarly tested. The techniques were validated using uterine sections from day 8.5 of CBA x DBA/2 pregnancies, and then were applied to sections of placentae from normal and pre-eclamptic pregnancies with and without intrauterine fetal growth restriction (IUGR). Fibrin was detectectd by immunohistochemistry. RESULTS: Expression of fg12 protein correlated with fg12 mRNA expression in mouse uteri and in placentae from normal human pregnancies. Increased expression of fg12 and TNF-alpha mRNA and protein, and increased fibrin deposition was detected in placental trophoblast. CONCLUSIONS: Activation of fg12 prothrombinase by Th1-type cytokines in pregnancy may lead to spontaneous abortion, or in ongoing pregnancy, to pre-eclampsia and/or IUGR.     

Adverse reproductive outcomes in urban women with adeno-associated virus-2 infections in early pregnancy

BACKGROUND: We demonstrated recently that adeno-associated virus-2 (AAV-2)DNA was detected significantly more frequently in placentaltrophoblast cells from cases of severe pre-eclampsia than fromnormal term deliveries. Here, we sought to determine if maternalAAV-2 infection early in pregnancy preceded adverse outcomesresulting from placental dysfunction. METHODS: We collected first trimester maternal serum samples and comparedanti-AAV-2 IgM antibody levels (indicating primary infectionor reactivation of latent AAV-2) between controls deliveredat term (n = 106) and three groups of cases: spontaneous abortions(n = 34), spontaneous preterm deliveries (n = 24) and womenwith at least one outcome usually attributed to placental dysfunction,including pre-eclampsia, intrauterine growth restriction (IUGR)or stillbirth (n = 20). The seroprevalence of immunoglobulinG (IgG) antibodies against AAV-2 and IgM antibodies againstviruses that promote AAV-2 replication [adenovirus and cytomegalovirus(CMV)] were also determined. RESULTS: First trimester maternal IgM seropositivity was 5.6 times moreprevalent among pre-eclampsia/IUGR/stillbirth cases (P = 0.0004)and 7.6 times more prevalent among preterm deliveries (P <0.0001) than among controls. CMV and adenovirus IgM antibodiesand chronic AAV-2 infections (IgG seropositivity) were not associatedwith adverse pregnancy outcomes. CONCLUSIONS: Primary or reactivated AAV-2 infection (maternal IgM seropositivity)early in pregnancy was associated with adverse reproductiveoutcomes associated with placental dysfunction, including pre-eclampsia,stillbirth and spontaneous preterm delivery.     

The role of insulin-like growth factor binding protein-1 phosphoisoforms in pregnancies with impaired placental function identified by doppler ultrasound.

This study was performed to investigate the hypothesis that insulin-like growth factor binding protein-1 (IGFBP-1) is involved in the pathogenesis of trophoblast invasion and impaired placentation in human pregnancy. The role of total and non-phosphorylated IGFBP-1 in women with fetal growth restriction and in high risk pregnancies identified by uterine artery Doppler ultrasound screening was examined. This was a prospective study of women booked for antenatal care having second trimester anomaly scans and Doppler screening between 22-26 weeks gestation. Women were divided into three groups and compared: normal uterine artery Doppler and normal fetal growth (control group, n = 10); abnormal Doppler and normal fetal growth [bilateral uterine artery notches (BN; n = 16); abnormal Doppler and intrauterine growth restriction (IUGR; n = 8)]. Maternal serum was collected, stored and assayed simultaneously for total and non-phosphorylated IGFBP-1. There was elevated total and non-phosphorylated IGFBP-1 (mean 44.99 +/- 12.19 and 29.61 +/- 10.38 microg/l respectively) in the IUGR group compared with controls (mean 17.96 +/- 3.24 and 12.18 +/- 1.55 microg/l, P < 0.05). This finding suggests that the various IGFBP-1 isoforms, the degree of phosphorylation and the ratios of these different forms locally may be important during trophoblast invasion and may be implicated in clinical manifestations of impaired placentation later in the second trimester.     

Interleukin-2 receptor serum concentrations in normal pregnancy and pre-eclampsia

The purpose of this research was to assess interleukin-2 receptor serum levels in normal pregnancy and pre-eclampsia. Sera from 90 healthy pregnant women (30 for each trimester), 30 with pre-eclampsia and a group of 30 healthy non-pregnant were analyzed. Soluble interleukin-2 receptor was measured by specific double antibody enzymatic immunoassay (ELISA). Results were: 267.5 +/- 12.3 (mean +/- s.e.m) pg/mL in the uncomplicated first trimester sample, 300.9 +/- 14.5 pg/mL in the second trimester and 248.8 +/- 12.5 pg/mL in the third. The non-pregnant control group had 443.7 +/- 39.6 pg/mL, significantly different from normal pregnancy in all trimesters (p < 0.001). The concentration in pre-eclamptic patients was 382.2 +/- 24.2 pg/mL, with p < 0.01 with regard to the normal third trimester group. The conclusion is that interleukin-2 receptor serum levels diminish in normal pregnancy and rise in preeclampsia. The first finding seems to be a protective mechanism to the fetal allograft. The latter, point to increased cellular activity.     

Choriocarcinoma-like human chorionic gonadotrophin (HCG) and HCG bioactivity during the first trimester of pregnancy

The objective of this study was to evaluate the distribution of choriocarcinoma-like human chorionic gonadotrophin (HCG) isoforms during first trimester pregnancy and their relationship with in-vitro HCG bioactivity. This was done by means of a retrospective analysis of patients' sera with first trimester normal intrauterine and abnormal (ectopic) pregnancies. Serum samples were obtained from 38 women with an amenorrhoea of <10 weeks. From these, 19 had a normal intrauterine pregnancy (IUP) and 19 an ectopic pregnancy (EP). Total immunoreactive HCG (HCGi), free beta-HCGi and oestradiol were measured by enzyme immunoassays and bioactive HCG by the mouse Leydig cell bioassay. The alterations in HCG isoform content were measured by the combination of two immunometric assays, B152 for choriocarcinoma-like HCG and B109 for intact HCG detection and expressed as the B152/B109 ratio. Choriocarcinoma-like HCG isoforms ratio measured by B152 and B109 assays was significantly higher in the low subgroups of free beta-HCGi and gestational age (P = 0.0111 and 0.0036 respectively). Whereas bioactive to immunoreactive HCG ratios (b/i ratio) were significantly higher when free beta-HCGi concentrations were low (P = 0.0010), no correlation was found between the variation of bioactivity (b/i ratio) and the proportion of choriocarcinoma-like HCG isoforms (B159/B108). It is concluded that in first trimester pregnancies (i) the modulation of HCG in-vitro bioactivity is not related to the variation of choriocarcinoma-like HCG isoforms secretion and (ii) the amount of choriocarcinoma-like HCG isoforms secreted by the early trophoblast is predominant and may be the result of an early developmental regulation of glycosylation enzyme.     

Serum levels of CA 125 during the first trimester of normal outcome, ectopic and anembryonic pregnancies

Single serum samples were obtained during the first trimester of pregnancies with a retrospectively normal outcome (n = 150), ectopic pregnancies (n = 38) and anembryonic pregnancies (n = 78). Serial samples during the first trimester were also obtained from 43 women achieving pregnancy following successful treatment for infertility and with a retrospectively defined normal outcome. Significant variation in serum CA 125 levels in relation to gestational age was observed in pregnancies with a normal outcome (P less than 0.0001). Peak serum CA 125 levels were observed at 6-7 weeks, the mean level at this gestation being 40.1 U/ml (range 31.7-50.7 U/ml) in the normal conception/normal outcome group and 36.5 U/ml (range 25.6-52.0 U/ml) in the assisted conception/normal outcome group. A rise and fall in serum CA 125 levels during the first trimester was observed in 42 of 43 assisted conceptions monitored serially, with peak levels ranging from 7 to 1398 U/ml (median 48.8 U/ml) occurring at 28-61 days (median 45 days) gestation. Mean serum CA 125 levels were higher in the anembryonic pregnancy group at 4-5 and 6-7 weeks gestation than in both normal pregnancy outcome groups (P less than 0.01).     

Supporting the hypothesis of pregnancy as a tumor: survivin is upregulated in normal pregnant mice and participates in human trophoblast proliferation

PROBLEM: Survivin, a tumor-promoting antiapoptotic molecule, is expressed in the human placenta. Here, we analyzed its expression during normal and pathological murine pregnancy and investigated its participation in human first trimester trophoblast cell survival and proliferation. METHOD OF STUDY: We first analyzed the expression of survivin on the mRNA and protein level at the fetal-maternal interface of normal pregnant (CBA/J x BALB/c) and abortion-prone (CBA/J x DBA/2J) mice at different pregnancy stages by RT-PCR and immunohistochemistry. We also evaluated apoptosis in murine trophoblasts in both mating combinations by TUNEL technique. Functional studies were carried out by knockdown survivin by means of siRNA methodology in two human first trimester trophoblast cell lines [Swan.71 (Sw.71) and HTR8 (H8)]. RESULTS: We observed a peak in mRNA levels on day 5 and a peak of protein levels on day 8 of pregnancy in both combinations. The level of survivin in animals from the abortion-prone group was decreased compared with normal pregnant mice on day 8, which was accompanied by elevated apoptosis rates. In later pregnancy stages (days 10 and 14), survivin levels decreased to levels comparable to those observed right after fecundation in both groups. Transfection of human first trimester cell lines (H8 and Sw.71) with siRNA targeting the survivin gene led to a 76-82% reduction of its expression leading to reduced trophoblast cell viability and proliferation. CONCLUSION: Our findings suggest an important role of survivin to promote trophoblast cell survival and proliferation during placentation, thus maintaining pregnancy. The pregnancy-associated expression of a cancer molecule such as survivin supports the 'pseudo-malignancy' hypothesis of pregnancy. Our data may contribute to the better understanding of trophoblast cell development during implantation and placentation.     

妊娠高血压疾病孕妇血胱抑素C与尿素氮、肌酐检测结果的分析

目的探讨孕妇血清胱抑素C（Cys C）、尿素氮（BUN）和肌酐（Cr）与妊娠期高血压疾病的关系。方法用日立7180全自动生化分析仪对50例妊娠期高血压疾病孕妇及50例妊娠中晚期正常孕妇进行血清Cys C、BUN、Cr的检测。结果重度及轻度子痫前期组Cys C值明显高于正常孕妇组（P〈0.01）,且有显著性差异,重度子痫前期组Cys C明显高于轻度子痫前期组,有显著性差异（P〈0.05）;而重度子痫前期组BUN、Cr明显高于正常孕妇组（P〈0.01）,有显著性差异,但轻度子痫前期组BUN、Cr与正常孕妇组相比,无显著性差异（P〉0.05）。结论血清Cys C的检测对于妊娠期高血压疾病的肾功能损害具有较好的诊断价值,联合检测血清Cys C、BUN、Cr有利于HDCP及其并发的肾功能损害的诊断及监测。     

Decreased serum levels of macrophage migration inhibition factor in miscarriages with normal chromosome karyotype

BACKGROUND: The aim of this study was to determine serum concentrations of macrophage migration inhibition factor (MIF) during normal pregnancies, and to assess whether serum MIF concentrations early in pregnancies predict the subsequent outcome in women with recurrent miscarriage (RM). METHODS: Serum MIF concentrations were measured by ELISA. Sera were collected from normal women in the first (Group I, n = 29), second (Group II, n = 25) and third trimester (Group III, n = 26) and from 78 RM women at 4-6 weeks gestation. Eleven of these 78 pregnancies subsequently ended in first trimester miscarriage with normal fetal chromosome karyotype (MsNK), seven ended in first trimester miscarriage with abnormal karyotype (MsAK), and three ended in biochemical pregnancy. The other 57 pregnancies ended in live birth (LB) between 32-41 weeks gestation, and only one woman developed preeclampsia. RESULTS: Median MIF concentrations in Group I, II and III were similar at 17.6, 16.4 and 15.1 ng/ml respectively. MIF concentrations during early gestation in RM women with subsequent MsNK, MsAK and LB were 8.1, 11.4 and 16.4 ng/ml respectively. MIF concentrations in RM women with MsNK were significantly lower than those in RM women with LB (P < 0.01) and than those in Group I (P < 0.01), II (P < 0.05) and III (P < 0.05). CONCLUSIONS: Decreased serum MIF concentrations during early gestation were found in RM women with MsNK, and might be related to the aetiology of miscarriage.     

Heme oxygenases in pregnancy II: HO-2 is downregulated in human pathologic pregnancies

PROBLEM: We previously reported a diminished expression of the heme-degrading enzymes heme oxygenases (HO)-1 and HO-2 in decidua and placenta from mice undergoing Th1-mediated abortion, strongly indicating the protective effect of HO in murine pregnancy maintenance. Here we investigated whether the expression of HO-1 and HO-2 is also reduced at the feto-maternal interface of pathologic human pregnancies. METHOD OF STUDY: Immunohistochemistry was used to detect HOs expression in placental and decidual first-trimester tissue from patients with: spontaneous abortion (n = 14), choriocarcinoma (n = 14), hydatidiform mole (H-mole) (n = 12), compared with normally progressing pregnancies (n = 15). Further, we investigated early third-trimester decidual and placental tissue from patients with pre-eclampsia (n = 13) compared with fetal growth retardation (n = 14) as age-matched controls. RESULTS: In first trimester tissue, we observed a significant reduction of HO-2 expression in invasive trophoblast cells, endothelial cells, and syncytiotrophoblasts in samples from patients with spontaneous abortion compared with normal pregnancy. H-mole samples showed a diminished expression of HO-2 in invasive trophoblast cells and endothelial cells in comparison with NP, whereas choriocarcinoma samples showed no significant differences compared with the control. In third trimester tissue, HO-2 was also reduced in syncytiotrophoblasts and invasive trophoblast cells from pre-eclampsia compared with samples from fetal growth retardation. HO-1 expression was diminished in all pathologies investigated; however, the differences did not reach levels of significance. CONCLUSIONS: Our data indicate that HOs play a crucial role in pregnancy and low expression of HO-2, as observed in pathologic pregnancies, may lead to enhanced levels of free heme at the feto-maternal interface, with subsequent upregulation of adhesion molecules, allowing enhanced inflammatory cells migration to the feto-maternal interface.     

Placental protein 13 (galectin-13) has decreased placental expression but increased shedding and maternal serum concentrations in patients presenting with preterm pre-eclampsia and HELLP syndrome

Placental protein 13 (PP13) is a galectin expressed by the syncytiotrophoblast. Women who subsequently develop preterm pre-eclampsia have low first trimester maternal serum PP13 concentrations. This study revealed that third trimester maternal serum PP13 concentration increased with gestational age in normal pregnancies (p < 0.0001), and it was significantly higher in women presenting with preterm pre-eclampsia (p = 0.02) and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome (p = 0.01) than in preterm controls. Conversely, placental PP13 mRNA (p = 0.03) and protein, as well as cytoplasmic PP13 staining of the syncytiotrophoblast (p < 0.05) was decreased in these pathological pregnancies compared to controls. No differences in placental expression and serum concentrations of PP13 were found at term between patients with pre-eclampsia and control women. In contrast, the immunoreactivity of the syncytiotrophoblast microvillous membrane was stronger in both term and preterm pre-eclampsia and HELLP syndrome than in controls. Moreover, large syncytial cytoplasm protrusions, membrane blebs and shed microparticles strongly stained for PP13 in pre-eclampsia and HELLP syndrome. In conclusion, parallel to its decreased placental expression, an augmented membrane shedding of PP13 contributes to the increased third trimester maternal serum PP13 concentrations in women with preterm pre-eclampsia and HELLP syndrome.     

A longitudinal study of maternal plasma insulin-like growth factor binding protein-1 concentrations during normal pregnancy and pregnancies complicated by pre-eclampsia

Insulin-like growth factor binding protein-1 (IGFBP-1) is synthesized by the decidual stroma, and is thought to act locally to inhibit IGF activity and so limit trophoblast invasion. Cross-sectional studies have reported conflicting data on maternal circulating concentrations of IGFBP-1 in early pregnancy before the development of pre-eclampsia. A longitudinal study was performed in 10 women who went on to develop pre-eclampsia and a group of 12 normal pregnant controls, chosen to be similar for maternal age, booking body mass index (BMI) and gestational age. Maternal IGFBP-1 concentrations were measured in plasma obtained at 16, 20, 24, 28, 32 and 36 weeks. Plasma IGFBP-1 concentrations were unchanged over this period in normal pregnancy. In contrast, the concentrations in women who developed pre-eclampsia increased progressively. At 16, 20, and 24 weeks the concentrations were significantly lower compared to normal pregnancy, at 28 and 32 weeks, similar, but by 36 weeks the concentrations were significantly greater than the normal controls. The data show that circulating IGFBP-1 concentrations are lower in early pregnancy before the development of pre-eclampsia. Thus, it is suggested that IGFBP-1-induced inhibition of IGF activity is unlikely to be responsible for the impaired trophoblast invasion observed in pre-eclampsia.     

Secretory endometrial protein PP14 in women with early pregnancy bleeding.

The decidualized endometrium produces secretory proteins of which secretory endometrial protein PP14 is the major product during the first trimester of pregnancy. The protein is secreted into the uterine lumen as well as into the peripheral blood. The purpose of this study was to examine whether decidual function, evaluated by the serum concentration of PP14, was different in women with early pregnancy bleeding compared to normal pregnant women. A reference range for serum PP14 was established on the basis of single samples from 236 normal pregnant women with ultrasonically confirmed gestational age. All the women were delivered of a normal child at term. The study comprised 128 pregnant women admitted because of vaginal bleeding between 6 and 18 weeks gestation. At ultrasonography, intrauterine fetal heart activity was either present or was confirmed at a subsequent examination. No difference was found in the serum level of PP14 compared to that in normal pregnancies, but women with vaginal bleeding and depressed PP14 levels appeared to have a 5-fold higher risk of preterm delivery than women with bleeding and normal PP14 levels.     

Soluble HLA-DR and soluble CD95 ligand levels in pregnant women with antiphospholipid syndromes

Antiphospholipid syndrome (APS) is a severe complication in pregnancy that can lead to fetal death in the second or third trimester. As soluble HLA-DR (sHLA-DR) molecules are reported to be implicated in the etiology of pregnancy disorders and of autoimmune diseases, we studied sHLA-DR plasma levels in pregnant women with APS (n = 14) and in women with normal pregnancy (n = 15), in women with high-risk pregnancies such as preeclampsia (PE; n = 20) and intrauterine growth retardation (IUGR; n = 10) and in fertile non-pregnant women (n = 29). The sHLA-DR levels of pregnant women were assessed during the third trimester, at labor, in the first week, and in the third month of puerperium. The results obtained were compared with soluble CD95 ligand (sCD95L), an important signal molecule in the apoptosis pathway. The sHLA-DR levels in pregnant women with APS were approximately three times higher (mean 1.48 +/- 0.15 microg/ml) during the whole observation period than in fertile non-pregnant women (0.54 +/-.06 microg/ml) and nearly double in women with high risk (PE, 0.91 +/- 14 microg/ml; IUGR, 0.94 +/-.21 microg/ml) and in normal pregnancies (0.74 +/- 0.13 microg/ml). Furthermore, sHLA-DR levels of pregnant women with APS were positively correlated with the serum concentration of anti-anticardiolipin immunoglobulin G antibodies. For sCD95L plasma levels, no substantial variations were found among the different groups above. In pregnant women with APS, however, sHLA-DR levels were positively correlated with sCD95L levels. Further studies should clarify the functional involvement of sHLA-DR molecules in the induction of CD95/CD95L-mediated apoptosis pathway that may play a crucial role in the pathology of pregnancies complicated by APS.     

Thyroid function tests in pregnancy

The recognition of abnormality in thyroid function tests during pregnancy is important for the welfare of the mother as well as fetus. The values of serum tri-iodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH) in nonpregnant women are not applicable during pregnancy and also differ in iodine deficient areas. In the present study, one hundred and twenty-four apparently normal, healthy young primigravidas with no known metabolic disorders and normal carbohydrate gestational intolerance test, consecutively attending the antenatal clinic were included in the study. The serum tri-iodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) in these women were estimated. In the first trimester, the mean T3 values were found to be 1.85 nmol/L, which increased to a mean of 2.47 nmol/L in the second trimester and declined in the third trimester to 1.82 nmo/L. Mean T4 levels were also seen to rise from 164.50 nmol/L in the first trimester to 165.80 nmol/L in the second trimester and then decreased in the third trimester to 159.90 nmol/L. Mean TSH levels were seen to rise progressively through the three trimesters of pregnancy from 1.20 microlU/ ml in the first trimester to 2.12 microlU/ml in the second trimester and further to 3.30 microlU/ml in the third trimester of pregnancy. Three asymptomatic pregnant women (2.5%) were found to have abnormal TSH values with normal T3 and T4 levels and good obstetric outcome. This pilot study also indicates the range to T3 as 1.7 - 4.3 nmol/L in second trimester and 0.4 - 3.9 nmol/L in third trimester, T4 as 92.2 - 252.8 nmol/L in second trimester and 108.2 - 219.0 nmol/ L in third trimester, and TSH as 0.1 - 5.5 microlU/ml in second trimester and 0.5- 7.6 microlU/ml in third trimester of pregnancy.