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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
591

Sorption, degradation and transport of estrogens and estrogen sulphates in agricultural soils

Scherr, Frank January 2009 (has links)
The fate and behaviour of estrogens in the environment are of concern due to the compounds’ endocrine disruption potential. Estrogens, namely 17β-estradiol (E2), estrone (E1), and estrogen sulphates, i.e. 17β-estradiol-3-sulphate (E2-3S) and estrone-3-sulphate (E1-3S) excreted by livestock constitute a potential source for estrogen contamination in the environment. A method was developed to separate and quantify the hormones by high-performance-liquid-chromatography (HPLC) and ultraviolet detection (UV). A combination of dichloromethane (DCM) and dicyclohexylamine hydrochloride (DCH·HCl) gave recoveries from 97.3 to 107% for E1-3S extraction from aqueous solutions. The recoveries from soil samples ranged from 80.9 to 95.2% (E2-3S), and from 86.3 to 91.7% (E1-3S), respectively. Results of batch sorption studies showed that Freundlich isotherms were nonlinear (N ≠ 1) with Kf values ranging from 34.2 to 57.2, and from 3.42 to 4.18 mg¹-N LN kg⁻¹ for E1, and E1-3S, respectively, indicating the sorption affinity of E1-3S was about an order of magnitude lower than that of E1. The hydrophilic sulphate group of E1-3S possibly shielded the compound from hydrophobic interactions with the soil organic matter and allophanic clay minerals that were proposed as sorbents for E1. Contraction of clay minerals, “salting out” and competitive sorption of artificial urine constituents were likely to have been responsible for observed changes in Freundlich parameters when artificial urine was used as mediator matrix. Plotting the effective distribution coefficient as a function of hypothetical exposure concentrations facilitated the comparison of the sorption behaviour of both compounds as influenced by the mediator solution. The results emphasized that using the CaCl₂ matrix might result in false inferences for the sorption behaviour of these compounds in a dairying environment. The four hormones rapidly degraded in the agricultural soils under aerobic conditions, and the majority of the compounds degraded > 50% within the first 24 hrs. Soil arylsulphatase activities were directly correlated with degradation rate constants of the estrogen sulphates. Estrone was identified as a metabolite of E2 and E1-3S, and these three compounds were observed as metabolites of E2-3S. Single-first order (SFO) and double first-order in parallel (DFOP) kinetics were used to model the degradation and metabolite formation data. The results showed that the DFOP model was in most cases better able to predict the parent compound degradation than the SFO model, and also enabled to estimate accurate degradation endpoints. ER-CALUX® analysis revealed the formation of estrogenicity during E2-3S degradation, which could partly be explained by the formation of the metabolites E2 and E1. Transport studies with E1-3S and E1 showed that the transport and retention of both compounds were significantly influenced by the mediator matrix. While no breakthrough curves (BTCs) were recorded during hormone application in CaCl₂ (10 mM) both hormones were detected in the leachate when applied in artificial urine. Rate-limited sorption processes were proposed for the delayed arrival of the hormone BTCs compared with a conservative bromide tracer. Intense colouration of the leachate during the artificial urine experiments suggested the hormones were likely to be moved by colloid-facilitated transport. Furthermore, the detection of residue hormone and metabolite concentrations implied that degradation of E1-3S and E1 was hampered by urine constituents such as glycine and urea.
592

Kurzzeiteffekte von Estradiol, Raloxifen, Phytohormonen und Parathormon auf die metaphysäre Frakturheilung des manifest osteoporotischen Knochens der Ratte / Effects of estradiol, raloxifene, cimicifuga racemosa, equol, genistein and parathyroid hormone on early metaphyseal fracture healing in osteoporotic rats

Daub, Florian 16 June 2010 (has links)
No description available.
593

"Alterações cognitivas em mulheres com quadros depressivos na perimenopausa: o efeito da terapia de reposição hormonal com estradiol transdérmico" / Cognitive alterations in perimenopaused women with clinical depression: estradiol transdermic hormone replacement therapy effects

Maria Fernanda Gouveia da Silva 06 April 2004 (has links)
A perimenopausa é a fase da vida reprodutiva feminina caracterizada diversas alterações, inclusive cognitivas devido ao hipoestrogenismo. Através de estudo duplo-cego randomizado com 16 mulheres na perimenopausa deprimidas que receberam estradiol e 16 que receberam placebo analisou-se as alterações cognitivas da atenção, memória e linguagem; o efeito da reposição hormonal com estradiol e a correlação entre os sintomas depressivos e menopausais com as alterações destas funções. Os resultados mostraram: melhora do controle inibitório, memória imediata e tardia (verbal e visual) e da capacidade de nomeação nos dois grupos; melhora dos sintomas depressivos e menopausais para o grupo que recebeu reposição hormonal: e não correlação entre a melhora destes sintomas e a melhora das funções cognitivas / Perimenopause is the female reproductive life period characterized by several changes including cognitive impairments related to hypoestrogenism. In a randomized double-blind study 16 depressive perimenopaused women took estradiol, while another group of 16 depressive perimenopaused women took placebo. Cognitive alterations associated to attention, memory and language, and estradiol hormone replacement therapy effects were evaluated. In addition, correlations among symptoms of depression and menopause, and cognitive alterations were also analyzed. The results had shown, in both groups, an improvement in inhibitory mental control, in immediate and delayed (verbal and visual) memory, and in naming capacity. In the group that received hormone replacement therapy our findings revealed a weakening of depression and menopause symptoms, which had shown no correlation with cognitive functions
594

The effect of hypoxia on ER-β expression in the lung and cultured pulmonary artery endothelial cells

Selej, Mona M.A. 12 March 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / 17-β estradiol (E2) exerts protective effects in hypoxia-induced pulmonary hypertension (HPH) via endothelial cell estrogen receptor (ER)-dependent mechanisms. However, the effects of hypoxia on ER expression in the pulmonary-right ventricle (RV) axis remain unknown. Based on previous data suggesting a role of ER-β in mediating E2 protection, we hypothesized that hypoxia selectively up-regulates ER-β in the lung and pulmonary endothelial cells. In our Male Sprague-Dawley rat model, chronic hypoxia exposure (10% FiO2) resulted in a robust HPH phenotype associated with significant increases in ER- β but not ER-α protein in the lung via western blotting. More importantly, this hypoxia-induced ER-β increase was not replicated in the RV, left ventricle (LV) or in the liver. Hence, hypoxia-induced ER-β up-regulation appears to be lung-specific. Ex vivo, hypoxia exposure time-dependently up-regulated ER-β but not ER-α in cultured primary rat pulmonary artery endothelial cells (RPAECs) exposed to hypoxia (1% O2) for 4, 24 or 72h. Furthermore, the hypoxia induced ER-β protein abundance, while not accompanied by increases in its own transcript, was associated with ER-β nuclear translocation, suggesting increase in activity as well as post-transcriptional up-regulation of ER-β. Indeed, the requirement for ER-β activation was indicated in hypoxic ER-βKO mice where administration of E2 failed to inhibit hypoxia-induced pro-proliferative ERK1/2 signaling. Interestingly, HIF-1α accumulation was noted in lung tissue of hypoxic ER-βKO mice; consistent with previously reported negative feedback of ER-β on HIF-1α protein and transcriptional activation. In RAPECs, HIF-1 stabilization and overexpression did not replicate the effects of ER- β up-regulation seen in gas hypoxia; suggestive that HIF-1α is not sufficient for ER-β up- regulation. Similarly, HIF-1 inhibition with chetomin did not result in ER-β down-regulation. HIF-1α knockdown in RPAECs in hypoxic conditions is currently being investigated. Hypoxia increases ER- β, but not ER-α in the lung and lung vascular cells. Interpreted in context of beneficial effects of E2 on hypoxic PA and RV remodeling, our data suggest a protective role for ER-β in HPH. The mechanisms by which hypoxia increases ER-β appears to be post-transcriptional and HIF-1α independent. Elucidating hypoxia-related ER-β signaling pathways in PAECs may reveal novel therapeutic targets in HPH.
595

Η επίδραση της αντισυλληπτικής αγωγής στους γενετικούς, αγγειακούς, βιοχημικούς και ορμονικούς πρώιμους δείκτες αυξημένου κινδύνου σε νέες γυναίκες με σύνδρομο πολυκυστικών ωοθηκών (PCOS)

Μαρκαντές, Γεώργιος 26 July 2013 (has links)
Σκοπός: η μελέτη της επίδρασης εξάμηνης θεραπείας με από του στόματος αντισυλληπτικό δισκίο περιέχον 35μg αιθινυλ-οιστραδιόλης και 2mg οξικής κυπροτερόνης στη γλοιότητα πλάσματος νέων γυναικών με σύνδρομο πολυκυστικών ωοθηκών. Σχεδίαση: Η γλοιότητα πλάσματος μετρήθηκε σε ασθενείς με σύνδρομο πολυκυστικών ωοθηκών πριν και 6 μήνες μετά από τη χορήγηση αντισυλληπτικού δισκίου περιέχοντος 35μg αιθινυλ-οιστραδιόλης και 2mg οξικής κυπροτερόνης. Η μέτρηση της γλοιότητας έγινε σε ιξωδόμετρο τύπου 53610/I SCHOTT-Instruments, Mainz στους 37ο C. Ασθενείς: Οι ασθενείς στρατολογήθηκαν από το τμήμα Αναπαραγωγικής Ενδοκρινολογίας της Μαιευτικής - Γυναικολογικής Κλινικής του Πανεπιστημιακού Νοσοκομείου Πατρών Ελλάδας. Στη μελέτη περιλήφθηκαν 66 νέες γυναίκες με σύνδρομο πολυκυστικών ωοθηκών. Βασικοί προσδιορισμοί: Γλοιότητα πλάσματος Αποτελέσματα: Στις ασθενείς ως σύνολο, η γλοιότητα πλάσματος ήταν 1.249±0.049 mm2/s (n=66). Μετά από 6 μήνες θεραπείας με από του στόματος αντισυλληπτικό δισκίο περιέχον 35μg αιθινυλ-οιστραδιόλης και 2mg οξικής κυπροτερόνης, η γλοιότητα πλάσματος αυξήθηκε σε 1.268±0.065 mm2/s (p=0.038). Η διαφορά στη γλοιότητα πλάσματος πριν και 6 μήνες μετά τη θεραπεία (Δ Γλοιότητας) ήταν 0,01864±,071452 mm2/s. Η Δ Γλοιότητας σχετιζόταν με τη Δ Ινωδογόνου (r=0.270, p=0.046), τη Δ Αιματοκρίτη (r=0.514, p=0.09) και τη Δ Τριγλυκεριδίων (r=0.292, p=0.021). Συμπέρασμα: Νέες γυναίκες με σύνδρομο πολυκυστικών ωοθηκών εμφάνισαν αυξημένη γλοιότητα πλάσματος μετά από θεραπεία με από του στόματος αντισυλληπτικό, το οποίο θα πρέπει για το λόγο αυτό να χρησιμοποιείται με προσοχή στον εν λόγω πληθυσμό. / Objectives: To investigate the influence of 6 months of treatment with an oral contraceptive (OC) containing 35μg ethinyl estradiol and 2mg cyproterone acetate on plasma viscosity in young women with PCOS. Design: PCOS patients were assessed for plasma viscosity before and after 6 months of treatment with an OC containing 35μg ethinyl estradiol and 2mg cyproterone acetate. Plasma viscosity was determined by a viscometer Type 53610/I SCHOTT-Instruments, Mainz at 37o C. Settings: Subjects were recruited from the Department of Obstetrics and Gynaecology, Division of Reproductive Endocrinology at the University Hospital of Patras, Greece. Patients: The study included 66 young PCOS women. Main Outcome measures: Plasma viscosity. Results: In PCOS women as a whole, plasma viscosity at baseline was 1.249±0.049 mm2/s (n=66). After 6 months of treatment with an oral contraceptive containing 35μg ethinyl estradiol and 2mg cyproterone acetate, plasma viscosity increased to 1.268±0.065 mm2/s (p=0.038). The difference between plasma viscosity before and after 6 months of treatment with an oral contraceptive containing 35μg ethinyl estradiol and 2mg cyproterone acetate (Δviscosity) was 0,01864±,071452 mm2/s. Δviscosity was related to Δfibrinogen (r=0.270, p=0.046), to Δhaematocrit (r=0.514, p=0.09) and to Δtriglycerides (r=0.292, p=0.021). Conclusion: Young PCOS women presented an increased plasma viscosity under OC treatment, which therefore should be used with caution.
596

Développement d’une approche toxicocinétique/toxicodynamique basée sur des mécanismes physiologiques pour évaluer les effets oestrogéniques du Bisphénol A / Development of a physiologically-based toxicokinetic/toxicodynamic approach to assess the estrogenic effects of Bisphenol A

Collet, Séverine 09 January 2012 (has links)
Ce travail a consisté à analyser, par des approches toxicocinétiques (TK) et mécanistiques, les effets oestrogéniques du Bisphenol A (BPA) sur un biomarqueur précoce et sensible : la sécrétion de l'hormone lutéinisante (LH) chez la brebis prépubère ovariectomisée. La plus faible concentration plasmatique en BPA induisant une inhibition de LH s'est avérée proche des concentrations maximales décrites chez l'Homme. Cette inhibition de LH pourrait impliquer une inhibition des systèmes neuronaux à kisspeptine. L'approche TK comparative d'espèces a montré que la clairance du BPA est toujours élevée, proche du débit sanguin hépatique. Pour une exposition à la dose journalière admissible, cette approche permet de prédire chez l'Homme des concentrations en BPA très inférieures à celles associées à une inhibition de LH dans notre modèle. / The goal of this thesis was to analyse through toxicokinetic (TK) and mechanistic approaches the estrogeno-mimetic effects of bisphenol A (BPA) on a precocious and sensitive biomarker: LH secretion in ovariectomized female lambs. The lowest plasma BPA concentrations associated to an inhibition of LH secretion appeared to be close to the highest one reported in human. LH suppression could be mediated by an inhibition of hypothalamic kisspeptin systems. The multispecies TK approach showed that BPA clearance is always high and equivalent to the liver blood flow. For an exposure scheme corresponding to the tolerable daily intake, this approach allows to predict human BPA concentration much lower than the one associated to LH inhibition in our highly sensitive lamb model.
597

Development of electrochemical ZnSe Quantam dots biosensors for low-level detection of 17β-Estradiol estrogenic endocrine disrupting compound

Jijana, Abongile Nwabisa January 2010 (has links)
<p>The main thesis hub was on development of two electrochemical biosensors for the determination of 17&beta / -estradiol: an estrogenic endocrine disrupting compound. Endocronology have significantly shown that the endocrine disruptors contribute tremendously to health problems encountered by living species today, problems such as breast cancer, reproductive abnormalities, a decline in male population most significant to aquatic vertebrates, reduced fertility and other infinite abnormalities recurring in the reproductive system of mostly male species. The first biosensor developed for the detection of 17&beta / -estradiol endocrine disrupting compound / consisted of an electro-active polymeric 3-mercaptoprorionic acid capped zinc selenide quantum dots cross linked to horseradish peroxidase (HRP) enzyme as a bio-recognition element. The second biosensor developed was comprised of cysteamine self assembled to gold electrode, with 3-mercaptopropionic acid capped zinc selenide quantum dots cross linked to cytochrome P450-3A4 (CYP3A4) enzyme in the presence of 1-ethyl-3-(3- dimethylaminopropyl)carbodiimide hydrochloride and succinimide.</p>
598

Behavioral effects of female sex steroid hormones : models of PMS and PMDD in Wistar rats

Löfgren, Magnus January 2009 (has links)
Background Animal models can be used to mimic human conditions of psychopathology, and also as pre-clinical models to evaluate candidate drugs. With hormonal treatment it is possible to produce behavior in the rat which corresponds to the mental symptoms of pre-menstrual syndrome (PMS), and pre-menstrual dysphoric disorder (PMDD). PMS affects 25-30 % of all women in fertile age and 3-8% are diagnosed with the more severe condition PMDD. The cardinal mental symptoms are; irritability, mood-swings, depression, anxiety, fatigue, insomnia, difficulties with concentration and memory and learning difficulties. The symptoms of PMS/PMDD occur in the luteal phase in conjunction with increasing concentrations of progesterone (P4) and P4-metabolites. In anovulatory cycles the symptoms are absent. The hormones which produce the monthly reoccurring negative symptoms on mood are foremost the neuroactive metabolites; allopregnanolone (ALLO) and tetrahydro-deoxycorticosterone (THDOC). ALLO is produced by the corpus luteum, but can also be synthesized in the brain, both ALLO and THDOC can also be released from the adrenal cortex during stress. These steroids are active on the inhibitory GABA neurotransmitter system through the GABAA receptor, and the effects are similar to that of alcohol and benzodiazepines. These steroids have strong sedative and hypnotic effects. A paradox is that some individuals seem to react with negative mood on sex steroids while all fertile women have the cyclical steroid changes during the menstrual cycle. Some individuals are more sensitive to neuroactive steroids with influences of personality, heritability and stress factors. Aims The thesis aims were to develop pre-clinical animal models of PMS/PMDD and to investigate induction of ALLO tolerance, individual sensitivity to neurosteroids and the interactions between chronic social stress and neurosteroids. Methods In these studies male and female Wistar rats were used to test steroid hormone effects on learning and memory and behaviors analogous to negative mood symptoms. This was accomplished through hormonal treatment and a subsequent withdrawal period from P4 (P4) + estradiol (E2) (PEWD), or ALLO. To assess tolerance, memory and learning in the Morris water maze (MWM) was studied. Anxiety-like behaviors were tested with the elevated plus maze (EPM), open field test (OFT), and the intruder test (IT). The EPM or OFT was used to classify the rats as high or low responders on risk-taking and explorative behavior (HR/LR). For social ranking order assessment the tube test (TT) and food competition test (FCT) were used. Chronic social stress was accomplished through co-habituation with two older rats (chronic subordination stress). In female rats the estrous cycle followed using staining of vaginal smears. Concentration of corticosterone (CORT) was measured by radio-immuno-assay (RIA). Results In the MWM ALLO pre-treatment produced tolerance to the acute negative ALLO effects. Both male and female rats showed behavioral correlations between the EPM and OFT tests, and correlations were also seen in CORT levels. Individuals with the stable trait of high risk-taking and explorative behavior (HR) were more sensitive to PEWD induction of anxiety-like behavior. These animals also showed decreased CORT levels during withdrawal. Chronic subordination stress enhanced the response to PEWD on measures of locomotor activity and social anxiety-like behavior. Conclusions It is possible to induce tolerance to the negative ALLO effects on learning and memory. The animal models of anxiety-like behavior show an individual PEWD response profile where HR rats are more sensitive. Exposure to chronic social stress enhanced the PEWD response. Hence there are both inherent and environmental factors behind the behavioral response to steroid hormones in rats. / Stress- och könshormoners verkningar på centrala nervsystemet
599

Endocrine and molecular regulation of ovarian antral follicular wave emergence and growth in sheep

Seekallu, Srinivas 21 October 2009
In sheep, large ovarian antral follicles grow in waves with a periodicity of every 4 to 5 days; each wave is initiated by a peak in serum concentrations of follicle stimulating hormone (FSH). In the present thesis, follicular data and hormone estimations acquired from daily ultrasonography and blood samples, respectively, were used to study mechanisms regulating the number of follicular waves per estrous cycle. Using additional approaches such as implants releasing estradiol-17â and or progesterone, immunization against gonadotropin releasing hormone (GnRH), and injections of GnRH, the role of pulsed luteinizing hormone (LH) secretion and FSH peaks in follicular wave emergence and growth and the dependency of FSH peaks on pulsed GnRH secretion, were studied in sheep. The viability of aged follicles was also addressed.<p> The results of the present studies showed that ewes with three or four waves per cycle had cycles of the same length. The inter-wave interval was longer for the first and the last or ovulatory wave of the cycle in three compared to four wave cycles. The length of the lifespan and regression phase of the largest follicle of a wave declined across the cycle as FSH peak concentration and amplitude decreased. The maximum follicular diameter of the largest follicle growing in the first wave and the last or ovulatory wave of the cycle was greater compared to other waves of the cycle. Treatment of anestrous ewes with estradiol releasing implants alone completely abolished pulsed LH secretion and suppressed follicular wave development; however, FSH secretion was only minimally affected and the pool of small follicles was not affected. When pulsed secretion of LH was restored by frequent injections of GnRH, follicular waves were re-established. Treatment of anestrous ewes with implants releasing estradiol and progesterone, decreased FSH peak amplitude and abolished LH pulses and follicular waves; the size of the pool of small follicles increased. Immunization against GnRH in anestrous ewes abolished pulsatile LH secretion and suppressed follicular wave emergence; however, FSH peaks continued to occur for several weeks. In cyclic ewes, creating an LH pulse frequency typical of the follicular phase, during the luteal phase of the cycle by giving GnRH, increased maximum diameter of the largest follicle in a wave and serum concentrations of estradiol and progesterone. The enhanced growth of follicles in a wave blocked the next expected FSH peak and its associated follicular wave. Decreasing LH pulse frequencies lower than the minimal frequency seen in the luteal phase, by implants releasing progesterone, did not affect the growth of follicular waves.<p> It was previously demonstrated that treatment of non-prolific WWF ewes with Prostaglandin F2á (PGF2á) and medroxy progesterone acetate (MPA) increased the ovulation rate by adding ovulations from the penultimate wave in addition to the final wave of the cycle; however, fertility was not improved. In the last study of my thesis, we collected follicles, with an extended lifespan, from the penultimate wave of the cycle in ewes given the PGF2á and MPA treatment. We compared their quality with follicles from the final wave of the cycle by looking at the expression of markers of follicular development. The results showed that theca cells of follicles from the final wave had significantly higher mRNA expression for vascular endothelial growth factor (VEGF) compared to follicles from the penultimate wave. Granulosa cells of follicles from the final wave had significantly higher mRNA expression for connexion 43 (Cx43) compared to follicles from the penultimate wave. Protein expression for Cx43, proliferating cell nuclear antigen (PCNA) and Factor VIII was greater in follicles from the final compared to the penultimate wave.<p> We concluded from the present studies that: 1) the mechanism that makes a three wave or four wave cycle is unclear; 2) some level of pulsatile LH secretion is required for an FSH peak to trigger emergence of follicular waves in anestrous ewes; 3) progesterone enhances the inhibitory effects of estradiol on FSH secretion in anestrous ewes, suppressing specifically FSH peak amplitude; 4) an endogenous rhythm may exist that drives the peaks in FSH secretion independent of secretory products from the follicles growing in a wave and pulsed GnRH secretion; 5) follicular waves in ewes, when exposed to an LH pulse frequency similar to the follicular phase, during the luteal phase of the cycle, when serum progesterone concentrations are high, can grow and function like ovulatory follicles growing in the follicular phase of the cycle; 6) expression of some markers of vascularization/ angiogenesis, gap-junctional communication and cell proliferation, appeared to be decreased in follicles from the penultimate compared to the final wave of an estrous cycle, when the lifespan of follicles from the penultimate wave was extended such that they were present in the ovary with follicles from the final wave of the cycle.
600

Physiological Stress Reactivity in Late Pregnancy

Hellgren, Charlotte January 2013 (has links)
During pregnancy, the basal activity is increased in both of our major stress response systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis. At the same time, the reactivity towards stressors is reduced. These alterations sustain maternal and fetal homeostasis, and are involved in the regulation of gestational length. Although the feto-placental hormone synthesis produces the main endocrinological changes, also the central nervous system undergoes adaptation. Together, these profound adjustments have been suggested to make women’s mental health more vulnerable during pregnancy and postpartum period. The aim of this thesis was to examine factors connected to physiological stress responses during the late pregnancy in relation to pain, labour onset, emotional reactivity, and mental health. The first study examined the pain and sympathetic response during cold stress, in relation to time to delivery. Women with fewer days to spontaneous delivery had lower sympathetic reactivity, while no pain measure was associated with time to delivery. In the second study, acoustic startle response modulation was employed to study emotional reactivity during late gestation, and at four to six weeks postpartum. The startle response was measured by eye-blink electromyography, while the participants watched pleasant and unpleasant pictures, and positive and negative anticipation stimuli. A significant reduction in startle modulation by anticipation was found during the postpartum assessment. However, no startle modulation by pleasant, or unpleasant, pictures was detected at either time-point. The serum level of allopregnanolone, a neurosteroid implied in pregnancy-induced hyporeactivity, was analysed in relation to self-reported symptoms of anxiety and depression. Although the participants reported low levels of depression, the women with the highest depression scores had significantly lower levels of serum allopregnanolone. There was no correlation between allopregnanolone and anxiety scores. In the fourth study, the cortisol awakening response was compared between women with depression during pregnancy, women with depression prior to pregnancy, and women who had never suffered from depression. No group differences in cortisol awakening response during late pregnancy were found. The results are in line with the previously described pregnancy-induced hyporesponsiveness, and add to the knowledge on maternal stress hyporeactivity, gestational length, and maternal mental health.

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