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Hanbury-Brown and Twiss exchange and non-equilibrium-induced correlations in disordered, four-terminal graphene-ribbon conductor. Sci Rep 2018; 8:14952. [PMID: 30297734 PMCID: PMC6175907 DOI: 10.1038/s41598-018-32777-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 09/11/2018] [Indexed: 11/09/2022] Open
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Long-term clinical and economic outcomes in previously untreated paediatric patients with severe haemophilia A: A nationwide real-world study with 700 person-years. Haemophilia 2018; 24:436-444. [DOI: 10.1111/hae.13447] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2018] [Indexed: 11/28/2022]
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Decreased spermatogonial quantity in prepubertal boys with leukaemia treated with alkylating agents. Leukemia 2017; 31:1460-1463. [PMID: 28270690 PMCID: PMC5467043 DOI: 10.1038/leu.2017.76] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Inhibitor development in previously untreated patients with severe haemophilia A: a nationwide multicentre study in Finland. Haemophilia 2016; 22:721-9. [PMID: 27339837 DOI: 10.1111/hae.12974] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2016] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Currently the most serious treatment complication of haemophilia is the inhibitor development (ID), i.e. neutralizing antibody development. AIM This nationwide multicentre study in Finland evaluated the incidence and risk factors of ID in previously untreated patients (PUPs) with severe haemophilia A (FVIII:C < 0.01 IU mL(-1) ). METHODS We enrolled all PUPs (N = 62) born between June 1994 and May 2013 with at least 75 exposure days (EDs) to screen ID during follow-up extending to September 2013. RESULTS Thirteen ID (21% of 62) occurred; 10 (16% of 62) with high titre. Fifty-one patients (82%) were on primary prophylaxis (regular prophylaxis before the age of 2 and before the first joint bleed) from the median age of 11.4 months, 90% via a central venous access device. The initial product was rFVIII in 63% and pd-FVIII in 37%, moreover in 24% pd-FVIII was switched to rFVIII concentrate during the 75 EDs. Non-transient inhibitors developed in 9/51 (17.6%; 13.7% high titre) children with primary and in 4/11 (36.4%; 27.3% high titre) patients with secondary prophylaxis (P = 0.24). Overall, 74% had a high-risk genotype similarly distributed among the prophylaxis groups. The history of a major bleed enhanced ID (aHR, 4.0; 95% CI, 1.2-13.7), whereas FVIII treatment intensity or source and early implantation of ports did not increase ID risk. CONCLUSION The cumulative incidence of ID was low notwithstanding prevalent high-risk mutations. Despite patient-related risk factors, our management involving early intensive primary prophylaxis via ports helps to prevent bleeds and lower the incidence of inhibitors.
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Complications associated with central venous access device in children with haemophilia: a nationwide multicentre study in Finland. Haemophilia 2015; 21:747-53. [DOI: 10.1111/hae.12665] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2015] [Indexed: 01/05/2023]
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Cooper pair splitting by means of graphene quantum dots. PHYSICAL REVIEW LETTERS 2015; 114:096602. [PMID: 25793837 DOI: 10.1103/physrevlett.114.096602] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Indexed: 05/21/2023]
Abstract
A split Cooper pair is a natural source for entangled electrons which is a basic ingredient for quantum information in the solid state. We report an experiment on a superconductor-graphene double quantum dot (QD) system, in which we observe Cooper pair splitting (CPS) up to a CPS efficiency of ∼10%. With bias on both QDs, we are able to detect a positive conductance correlation across the two distinctly decoupled QDs. Furthermore, with bias only on one QD, CPS and elastic cotunneling can be distinguished by tuning the energy levels of the QDs to be asymmetric or symmetric with respect to the Fermi level in the superconductor.
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Infectious exposure in the first years of life and risk of central nervous system tumours in children: analysis of birth order, childcare attendance and seasonality of birth. Br J Cancer 2010; 102:1670-5. [PMID: 20461079 PMCID: PMC2883153 DOI: 10.1038/sj.bjc.6605679] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Background: An infective, mostly viral basis has been found in different human cancers. To test the hypothesis of a possible infectious aetiology for central nervous system (CNS) tumours in children, we investigated the associations with proxy measures of exposure to infectious disease. Methods: In a large case–control study nested in the populations of Denmark, Norway, Sweden, and Finland of 4.4 million children, we studied the association of birth order and seasonal variation of birth with subsequent risk for CNS tumours. We identified 3983 children from the national cancer registries, and information on exposure was obtained from the high-quality national administrative health registries. We investigated the association between childcare attendance during the first 2 years of life and the risk for CNS tumours in a subset of Danish children with CNS tumours, using information from the Danish Childcare database. Results: We observed no association between birth order and risk of CNS tumours overall (odds ratio (OR) for second born or later born vs first born, 1.03; 95% confidence interval (CI), 0.96–1.10) or by histological subgroup, and children with CNS tumours did not show a seasonal variation of birth that was distinct from that of the background population. Childcare attendance compared with homecare showed a slightly increased OR (1.29; 95% CI, 0.90–1.86) for CNS tumours, with the highest risk observed in children attending a crèche. The strongest association was observed for embryonal CNS tumours. We found no effect of age at enrolment or duration of enrolment in childcare. Conclusion: These results do not support the hypothesis that the burden of exposure to infectious disease in early childhood has an important role in the aetiology of paediatric CNS tumours.
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[From contraception to treatment of sexual health]. DUODECIM; LAAKETIETEELLINEN AIKAKAUSKIRJA 2001; 113:1157-8. [PMID: 11466844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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[Post-coital contraception]. DUODECIM; LAAKETIETEELLINEN AIKAKAUSKIRJA 2001; 113:1187-92. [PMID: 11466850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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The possible role of enterohepatic cycling on bioavailability of norethisterone and gestodene in women using combined oral contraceptives. Contraception 2001; 63:13-8. [PMID: 11257243 DOI: 10.1016/s0010-7824(00)00195-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using steady-state conditions we aimed to test if administration of oral activated charcoal affects the bioavailability of norethisterone acetate (NET Ac) and gestodene (GEST) by inhibiting their enterohepatic recirculation. Thirteen volunteers received, in a randomized order, Minulet (75 microg GEST and 30 microg ethinylestradiol [EE(2)]) and Econ/30 (1 mg NET Ac and 30 microg EE(2)), each for 4 months. Serum GEST and norethisterone (NET) levels were evaluated with respect to C(max,) t(max) and 24-h area under the curve (AUC(0-24h)) in the middle of the control (3rd) cycle and the charcoal treatment (4th) cycle during both pill treatments. No statistically significant difference was seen in any of the aforementioned variables between the control and charcoal treatment cycles of either pill. Neither was a difference seen in the bioavailability of GEST and NET as evaluated by the ratios of two 24-h AUCs calculated in the control and charcoal cycles of each pill treatment (p = 0.29). The results suggest that enterohepatic circulation of GEST and NET is not of clinical importance. We conclude that women on oral contraceptives can take activated charcoal for the treatment of diarrhea when administered 3 h after and at least 12 h before pill intake.
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Abstract
Ovulatory potential was studied during the use of two oral contraceptive pill preparations, after repeated mid-cycle administration of activated charcoal. Eleven women used monophasic pills containing gestodene, 75 microgram, plus ethinyl oestradiol, 30 microgram, or norethisterone acetate, 1 mg, plus ethinyl oestradiol, 30 microgram, for 4 months each, in randomized order. During both pill treatments the third cycle was a control cycle, and during the fourth cycle of both pill types, 5 g of activated charcoal was ingested four times a day, starting 3 h after pill intake, on cycle days 12, 13 and 14. Ovarian activity was monitored by intravaginal ultrasonography of follicles and by measurements of serum concentrations of LH, FSH, oestradiol and progesterone throughout the control and charcoal-treatment cycles of both pill treatments. None of the women ovulated. Follicular activity seen in two women did not correlate with charcoal administration. It is concluded that the possible enterohepatic recirculation of gestodene and norethisterone is not of clinical importance. Repeated charcoal treatment, when administered 3 h after but at least 12 h before pill intake, can be used to treat diarrhoea in women taking oral contraceptives.
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Abstract
The levonorgestrel intrauterine system (LNG IUS) releases 20 microg/24 h of levonorgestrel from a polymer cylinder mounted on a T-shaped frame and covered with a release rate-controlling membrane. It is approved for 5-year use. The most outstanding features of LNG IUS are its high contraceptive efficacy and reduction of menstrual blood flow. No single mode of action can account for its contraceptive efficacy. The endometrium becomes thin and inactive, and the cervical mucus turns scanty and viscous. Although ovulation may be disturbed to some degree, estradiol production continues normally. The Pearl index for LNG IUS from large clinical trials is 0.1. Extrauterine pregnancies occur in 1 in 5000 users per year. Both the volume of menstrual blood loss and the number of bleeding days are reduced. During the first year of use, 20% of women become amenorrheic. There is an initial increase in the mean number of bleeding and spotting days, but in 3 to 6 months the number of bleeding and spotting days is the same as observed in copper IUD-users. The variation between individuals is wide and unpredictable. There are also additional health benefits secondary to the inactivation of the endometrium: increased hemoglobin, decreased dysmenorrhea, a possible decrease in pelvic inflammatory disease. LNG IUS may also decrease the growth of fibroids. LNG IUS is well accepted by users, with typical annual continuation rates above 80% in clinical studies.
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Abstract
Several progestin-only long acting contraceptives are currently available in the form of implants or injectables. Vaginal rings are another contraceptive option in the final stages of development. These steroid-containing polymer rings are placed in the vagina, providing relatively constant drug release, thus allowing for lower effective doses. Vaginal rings have the advantage of being user-controlled and non-provider dependent, and their use is non-coital related. The first clinical study with medroxyprogesterone acetate vaginal rings was published in 1970. Since then numerous clinical trials testing different steroids and doses have followed. A large Phase III multicenter clinical trial with a levonorgestrel ring, releasing 20 microg/day, was coordinated and sponsored by WHO. The cumulative one-year pregnancy rate was 4. 5%. The principal reasons for discontinuation were menstrual disturbances (17.2%), followed by frequent expulsion of the ring (7. 1%), and vaginal symptoms (6.0%). The finding of erythematous lesions in the vagina in some women has led to the development of a more flexible device. Collaboration with industry should facilitate the manufacture of a redesigned levonorgestrel ring with a higher release rate. The Population Council is also developing a vaginal ring containing Nestorone for 6 months of continuous use. Ovulation inhibition was achieved in over 97% of the segments studied, with rings releasing either 50, 75, or 100 microg/day. No pregnancies occurred in women using the low-dose ring, while one pregnancy each occurred in the intermediate- and high-dose ring groups for a 6-month cumulative pregnancy rate of 0.0, 1.9, and 2.1%. Bleeding irregularities were common. Nestorone is orally inactive; therefore this ring is also excellent for use in lactating women.
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Abstract
Vaginal inspections using colposcopy before insertion of contraceptive vaginal rings and at 2-month intervals during ring use were conducted on 169 users of four different formulations. The rings studied released Nestorone alone (50, 75, 100 g daily over 6 months); ethinyl estradiol: Nestorone (30:100 and 15:150 g daily over 6 months); ethinylestradiol:norethindrone acetate (20:1000 and 15:1000 g daily over 4 months); and ethinyl estradiol:norethindrone acetate (20:1000 g daily over 12 months). A total of 88 altered or atypical conditions of the vaginal surface appearance were recorded in 507 inspections (17.4% of inspections). Many of these atypical appearances were quite subtle. The incidence was significantly higher (p <0.01) than in the single pretreatment examinations (11 in 158 inspections; 7.0%), but closely matched that of a "control group" of sexually active women who were the subject of an earlier study by the same investigators. In that study, the incidence was 18% (57 atypical conditions in 317 inspections). In all, 83% of atypical conditions identified in the vagina during ring use had disappeared by the next scheduled colposcopy despite continued ring use. Findings of potential significance were conservatively defined as all ulcerations, those abrasions and ecchymoses that were >0.5 cm in any direction, and fields of five or more petechiae. Findings fitting those criteria comprised 30% of atypical conditions in ring users, 33% in the control group, and 27% pretreatment. The corresponding incidence as a percentage of inspections were 5.3%, 6. 0%, and 2.5% in the ring users, control groups, and pretreatment groups, respectively. These differences were not statistically significant. The findings suggest that the vaginal rings included in the studies contributed little, if at all, to clinically significant lesions or to total lesion incidence. Further definition would require a larger and longer-term study with matched controls.
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Abstract
Contraception has mainly remained the responsibility of women. The sexually active time during the fertile period of life may last over 30 years and, increasingly, it is more than 10 years before the first baby. It is, therefore, natural that convenient long-acting contraceptive methods are becoming more and more appealing. The discovery of poly(dimethylsiloxane) as a carrier, and controlled release polymers for small molecule drugs allowed the development of contraceptive devices releasing steroids for several years. While contraceptive implants and intra-uterine systems are already marketed in many countries, contraceptive vaginal rings are in their late development phase. The key features of these long acting delivery systems are convenience, efficacy, reversibility and positive long-term health effects. Since these methods are based on new concepts, the provider needs to be prepared for extensive counselling.
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Pharmacokinetics of 7 alpha-methyl-19-nortestosterone (MENT) delivery using subdermal implants in healthy men. Contraception 1999; 60:299-303. [PMID: 10717782 DOI: 10.1016/s0010-7824(99)00095-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We studied the pharmacokinetics of 7 alpha-methyl-19-nortestosterone (MENT), a potent synthetic androgen, administered by subdermal implants. The implants contained 112 +/- 4 mg of MENT acetate in a polyethylene vinyl acetate copolymer. MENT acetate released from the implants is rapidly hydrolyzed to MENT in vivo. Fifteen healthy Finnish men were randomized to have either one, two, or four implants inserted in the medial aspect of the upper arm. The implants remained in place for 4 weeks. Blood samples were obtained before implant insertion, 1, 2, 3, and 4 weeks after insertion, and 1 and 2 weeks after removal. Serum MENT concentrations were determined by gas chromatography with mass selective detection. The MENT levels attained in each implant group remained at a steady level during the 4 weeks of implant use. The mean steady state MENT concentrations in the one, two, and four implant groups were 0.6, 1.4, and 2.3 nmol/L, respectively. Serum MENT concentrations during implant use were clearly dose dependent; the between-subject effect of implants as well as the differences between each pair of groups were all statistically significant. The release rate of MENT from one, two, and four implants was calculated to be approximately 0.3, 0.8, and 1.3 mg/day, respectively. This study suggests that MENT acetate implants are a promising method for long-term androgen administration in hypogonadism and male contraception.
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Abstract
The ovulatory potential of preovulatory follicles was studied in five women taking monophasic gestodene pills containing 20 micrograms of ethinyl estradiol. After one normal pill cycle, follicles were allowed to grow to 16 mm in diameter by deliberate extension of the pill-free period. Once the size of the leading follicle reached 16 mm, the women resumed oral contraceptives for the following 21 days to investigate whether ovulation can be inhibited by late onset of the pill. In addition, 100 micrograms of gonadotropin releasing hormone analog was given intravenously on the third pill day to induce ovulation. Follicular growth and activity were monitored by ultrasonography and by serum concentrations of ethinyl estradiol, progesterone, luteinizing hormone, and follicle stimulating hormone from the last pill day of the first cycle until the end of the second pill intake of 21 days. An increase in luteinizing hormone secretion started before intravenous administration of a gonadotropin releasing hormone analog in all women, eventually leading to ovulation in four of five women. One woman developed an unruptured follicle. Thus, the ovulatory potential of a 16-mm functional follicle cannot be inhibited by reintroduction of pills containing 20 micrograms ethinyl estradiol and 75 micrograms of gestodene.
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Gonadotrophin and testosterone suppression by 7alpha-methyl-19-nortestosterone acetate administered by subdermal implant to healthy men. Hum Reprod 1999; 14:2200-6. [PMID: 10469681 DOI: 10.1093/humrep/14.9.2200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The synthetic androgen 7alpha-methyl-19-nortestosterone (MENT) is a potent suppressor of gonadotrophin that has several advantages for long term administration to normal or hypoandrogenic men. The aim of this study was to examine MENT serum concentrations following subdermal insertion of MENT acetate (MENT Ac) implants and their effects on gonadotrophins, testosterone, dihydrotestosterone (DHT), sex hormone-binding globulin, prostate specific antigen and insulin-like growth factor-1 serum concentrations in normal men. A total of 45 healthy men were recruited at three clinics. Each subject received one, two or four implants for 28 days. Serum samples were obtained before insertion and on days 8, 15, 22, 29, 36 and 43 after implant insertion. The average daily dose delivered in vivo by one implant was approximately 500 microg. One, two or four MENT Ac implants produced dose dependent and sustained serum MENT concentrations for the entire duration of treatment of 0.7 +/- 0.1, 1.2 +/- 0.1 and 2.0 +/- 0.1 nmol/l respectively. This treatment induced a dose dependent decrease in gonadotrophin and androgen serum levels. Two and four implants induced maximal suppression that was maintained throughout treatment and was completely reversed after removal of the implants. The mean decreases were 93 +/- 1% for testosterone, 80 +/- 3% for DHT, 97 +/- 1% for luteinizing hormone and 95 +/- 1% for follicle stimulating hormone. No serious adverse reactions were reported by the volunteers and no consistent changes in clinical chemistry and haematology were found. These results indicate that MENT Ac implants are an efficient way of MENT administration and confirm the potent gonadotrophin and androgen suppressive effect of this drug.
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Variations in vaginal epithelial surface appearance determined by colposcopic inspection in healthy, sexually active women. Hum Reprod 1999; 14:1974-8. [PMID: 10438412 DOI: 10.1093/humrep/14.8.1974] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A total of 107 sexually active women, aged 18-35 years, was recruited through family planning clinics in four centres in different countries. Each woman underwent two or three gentle but thorough and systematic vaginal inspections using a consistent technique with colposcopic magnification over a 4-6 month period to look for changes in vaginal and cervical appearance which might be related to sexual intercourse, tampon use, contraceptive method used, cigarette smoking or other environmental factors. Obvious changes in appearance were photographed at x10 magnification. These 'appearances' or 'conditions' were classified according to a modification of the recommendations of a workshop sponsored by the World Health Organization, the Population Council and the Conrad Program. Most of these alterations in the appearance of the vaginal epithelium were judged to be of such minor clinical importance that they have been termed 'conditions' or 'changes in appearance' rather than 'lesions'. In all, 56 'conditions' or 'appearances' were noted in 314 inspections, the commonest being petechiae (53.6%). Potentially significant conditions justifying the term 'lesions' (three microulcerations, two ecchymoses, five abrasions and one mucosal tear; 3.5% of inspections) usually healed spontaneously and disappeared rapidly. The incidence of these conditions was highest when the inspections followed intercourse in the previous 24 h (25.2 versus 14.2%; P < 0.0008), or tampon use (32.4 versus 15.9%; P < 0. 0001). These processes may be regarded as a reflection of regular minor trauma to the vaginal epithelium.
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Parenteral administration of progestin Nestorone to lactating cynomolgus monkeys: an ideal hormonal contraceptive at lactation? Hum Reprod 1999; 14:1993-7. [PMID: 10438416 DOI: 10.1093/humrep/14.8.1993] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Nestorone (NES) progestin is highly effective for contraception following parenteral administration, but ineffective after oral ingestion due to rapid first-pass metabolism. Thus, NES might be ideal for lactational contraception; possible NES in milk should be metabolized by the nursing infant. We evaluated the distribution of NES, its endocrine effects and infant weight gain in five cynomolgus monkeys and their nursing infants. Nestorone implants, releasing approximately 40 microg NES/day in vitro, were placed s.c. in the mothers 3-4 months following delivery, where they remained in situ for 4 weeks. Sampling (blood daily from the mother; milk and blood from the infant at 3 day intervals) was initiated at 2 weeks prior to insertion, and continued for 2 weeks following removal of the implant. NES, oestradiol, progesterone and prolactin were measured by radioimmunoassays and the infants were weighed weekly. The (mean +/- SD) maternal serum and milk concentrations of NES were 337 +/- 90 and 586 +/- 301 pmol/l during the use of the implants. The ratio of milk/serum NES was 1.68 +/- 0.12 (mean +/- SE), and the serum and milk concentrations were significantly correlated (r = 0. 75, P < 0.001). NES was not detectable (<13 pmol/l) in any infant serum samples. Concentrations of prolactin (mean +/- SD) were 41.1 +/- 32, 26.7 +/- 7.6 and 26.3 +/- 9.5 ng/ml before, during and after the use of the implants respectively. The (mean +/- SE) infant weight increased from 643 +/- 54 g 1 week prior to insertion to 713 +/- 54 g 1 week following removal. These data confirm that NES in milk is rapidly metabolized by the suckling infant. Therefore, NES appears to be an ideal hormonal contraceptive for use during lactation.
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P-144. The effect of intrauterine levonorgestrel use on the ultrastructure and oestrogen and progestogen receptors of human endometrium. Hum Reprod 1999. [DOI: 10.1093/humrep/14.suppl_3.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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The effect of intrauterine and oral levonorgestrel administration on serum concentrations of sex hormone-binding globulin, insulin and insulin-like growth factor binding protein-1. Acta Obstet Gynecol Scand 1999; 78:423-8. [PMID: 10326889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND The concentrations of sex hormone-binding globulin (SHBG) have been shown to decrease during the use of levonorgestrel (LNG)-containing contraception. This decrease has been thought to be due to the androgenic action of LNG. In endogenously hyperandrogenic women, particularly in those with increased body weight, serum SHBG correlates with circulating insulin-like growth factor binding protein-1 (IGFBP-1) concentration, and both are inversely related to insulin. LNG-containing combined contraceptives have also been reported to increase the pancreatic insulin secretion. OBJECTIVE To examine whether serum insulin and IGFBP-1 levels are related to SHBG during the use of intrauterine or oral levonorgestrel contraception. METHODS Thirty-one fertile women were divided into three study groups: A copper-releasing intrauterine device (IUD) was inserted in control group (n= 10), and the LNG-releasing intrauterine contraceptive system (LNG-IUS) in group II (n= 10), and 30 mirog LNG-containing contraceptive minipills were given in group III (n=11). Twenty-nine women completed the study and one woman was excluded because of a high body mass index. Fasting concentrations of blood glucose, insulin, SHBG, IGFBP-1, testosterone and LNG before and after three-months-use of contraception were measured. RESULTS SHBG concentrations decreased slightly during oral LNG contraception, but not during the use of the LNG-IUS. No change was found in blood glucose, serum insulin, serum IGFBP-1 and serum total testosterone concentrations in either group. In our study group, including women with normal body weight, no correlation was detected between insulin and SHBG concentrations before or after LNG contraception, whereas an inverse correlation was found between insulin and IGFBP-1 levels at the baseline as well as after LNG-IUS use (R2= 0.578; p=0.001). Multiple regression analysis showed no significant association between the levels of SHBG and IGFBP-1 as dependent factors, and glucose, insulin, LNG, age, waist-hip ratio and body mass index as dependent factors. CONCLUSIONS Our data imply that the effect of levonorgestrel on variables associated with endogenous hyperandrogenism remains borderline in women with normal body mass index.
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[Breakthrough in thrombosis research--can the use of contraceptive pills be safer than it used to be?]. DUODECIM; LAAKETIETEELLINEN AIKAKAUSKIRJA 1998; 111:2097-8. [PMID: 9841168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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The ultrastructure of human endometrium is altered by administration of intrauterine levonorgestrel. Hum Reprod 1998; 13:1846-53. [PMID: 9740437 DOI: 10.1093/humrep/13.7.1846] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We studied the effect of intrauterine administration of levonorgestrel (LNG) on the ultrastructure of the endometrium. Twenty-one endometrial biopsy specimens, collected from nine fertile women during normal menstrual cycles and after 1, 3 or 6 months of use of a levonorgestrel-releasing intrauterine contraceptive system (LNG IUS), were studied using transmission and scanning electron microscopy. During the 6 month exposure to LNG IUS, changes took place in the endometrium. The glandular epithelial cells became lower. The junctional complexes between epithelial cells remained unchanged, whereas the lateral microvillar interdigitations became more prominent. The basal lamina under the epithelium became wavy but remained uniform and practically uninterrupted; only solitary epithelial cell protrusions through the basal lamina were seen. The stromal cells were largely decidualized. We conclude that in parallel with the generally known cellular effects, the use of the LNG IUS results in distinct changes in the basal lamina between the endometrial epithelial and stromal cells. The especially well-developed and uninterrupted basal lamina may be involved in the mechanism of the LNG IUS-induced endometrial suppression. Furthermore, the complex intercellular junctions between the epithelial cells, normally loosening around the time of implantation, persist during the local administration of levonorgestrel. This may have a pivotal role in the contraceptive effect of the LNG IUS.
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Abstract
OBJECTIVE Our purpose was to test the hypothesis that omitting the first three pills of the contraceptive cycle leads to ovulation. STUDY DESIGN Ninety-nine women, randomly assigned to 1 of 3 treatments of combined oral contraceptives, completed the study. Treatments contained ethinyl estradiol and either monophasic gestodene, triphasic gestodene, or monophasic desogestrel. Pituitary-ovarian activity was monitored by ultrasonography of the ovaries and assay of serum concentrations of estradiol, progesterone, and follicle-stimulating hormone over 1 normal cycle (study period 1) and 1 cycle after an extended pill-free interval of 10 days (study period 2). RESULTS None of the women experienced normal ovulation as evaluated by ultrasonography and serum progesterone concentrations. However, follicle-stimulating hormone reached a maximal serum concentration in most women during the first 7 pill-free days, indicating complete pituitary recovery, and increases in serum estradiol concentrations were seen in each woman although with marked interindividual variation. During study period 2 we found follicles of >18 mm in 24%, 24%, and 40% of the monophasic gestodene, triphasic gestodene, and monophasic desogestrel groups, respectively. CONCLUSIONS Follicular growth up to preovulatory size is common in women missing the first one to three pills of their contraceptive cycle. Although this creates the prerequisite for ovulation, normal ovulation did not occur when pill omissions were limited to only 3 days.
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Comparison of performances of two commercially available tests, a PCR assay and a ligase chain reaction test, in detection of urogenital Chlamydia trachomatis infection. J Clin Microbiol 1998; 36:1489-93. [PMID: 9620366 PMCID: PMC104866 DOI: 10.1128/jcm.36.6.1489-1493.1998] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The diagnostic performance of a PCR test (Roche Cobas Amplicor CT/NG Test) and that of a ligase chain reaction (LCR) test (Abbott LCx Chlamydia trachomatis assay) were compared by using endocervical and urethral swab specimen culture as a reference test. First-void urine (FVU) and endocervical and urethral swab specimens were collected from 1,015 unselected patients attending a sexually transmitted disease clinic and a clinic for adolescents in Helsinki, Finland. Chlamydia trachomatis was cultured from samples from the endocervix or urethra. PCR was performed with fresh and frozen urine and the culture transport medium. LCR was performed with fresh and frozen urine and LCx swab transport medium. Diagnostic consistency and diagnostic accuracy were statistically tested. The test results were identical for 984 patients (97%). Discrepant results were observed for 31 patients. Overall, LCR and PCR showed excellent kappa coefficients of consistency for both swab and FVU specimens (0.93 and 0.95, respectively). Sixty-one patients (6%) were culture positive. Testing of FVU by LCR or PCR increased the overall positivity rates to 7.0 and 7.7%, respectively. While PCR of FVU detected the greatest number of C. trachomatis infections (sensitivity, 96.1%), for some PCR-positive FVU specimens the results could not be confirmed (specificity, 99.6%). PCR and LCR were more sensitive than culture (sensitivities, 92 and 93% versus 79% for culture) in the diagnosis of genital C. trachomatis infection. In conclusion, both tests can be recommended for use in the clinical laboratory and for the screening of asymptomatic C. trachomatis infections.
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Open randomised study of use of levonorgestrel releasing intrauterine system as alternative to hysterectomy. BMJ (CLINICAL RESEARCH ED.) 1998; 316:1122-6. [PMID: 9552948 PMCID: PMC28513 DOI: 10.1136/bmj.316.7138.1122] [Citation(s) in RCA: 191] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES To assess whether the levonorgestrel intrauterine system could provide a conservative alternative to hysterectomy in the treatment of excessive uterine bleeding. DESIGN Open randomised multicentre study with two parallel groups: a levonorgestrel intrauterine system group and a control group. SETTING Gynaecology departments of three hospitals in Finland. SUBJECTS Fifty six women aged 33-49 years scheduled to undergo hysterectomy for treatment of excessive uterine bleeding. INTERVENTIONS Women were randomised either to continue with their current medical treatment or to have a levonorgestrel intrauterine system inserted. MAIN OUTCOME MEASURE Proportion of women cancelling their decision to undergo hysterectomy. RESULTS At 6 months, 64.3% (95% confidence interval 44.1 to 81.4%) of the women in the levonorgestrel intrauterine system group and 14.3% (4.0 to 32.7%) in the control group had cancelled their decision to undergo hysterectomy (P < 0.001). CONCLUSIONS The use of the levonorgestrel intrauterine system is a good conservative alternative to hysterectomy in the treatment of menorrhagia and should be considered before hysterectomy or other invasive treatments.
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Abstract
There is an urgent need to develop safe, effective, and acceptable vaginal products for the prevention of sexually transmitted infections. Preliminary in vitro results suggest that vaginal formulations of sulfated polysaccharides, including iota-carrageenan, have the potential to block mucosal transmission of human immunodeficiency virus (HIV). Twenty-five women in five sites participated in Phase I trials to evaluate the safety of a formulation containing iota-carrageenan (PC 213). The results of this study indicate that a 5 mL 2% gel formulation of iota-carrageenan is not associated with significant irritation of the female reproductive tract when administered once daily in the absence of sexual intercourse. Given the small number of participants in this initial study, careful observation for potential irritation must also be included in larger studies of this and other vaginal formulations.
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Abstract
Forty-two healthy women volunteered to have blood samples drawn at 2, 4, 8, 24, 48, and 168 h (7 days) following placement of levonorgestrel-releasing rod (LNG rod) or of Norplant capsule implants to permit measurement of drug concentrations. Three clinics recruited 10 women each, half of whom used each type of implant. Twelve additional subjects were later enrolled at one site to provide greater detail for the capsule implants. Throughout the week, women with Norplant implants had apparently higher mean drug concentrations than did women with LNG rod implants, but the differences were significant only in the first 48 h after placement (p < 0.05). Maximum levels for capsule implants were found at the 24-h sample (mean, 1358 to 1474 pg/mL) and for the LNG rod implants at 48 h (772 pg/mL). Body weight was negatively correlated with levonorgestrel concentrations at all times (p < 0.05). For several sampling times, differences between clinics in mean concentrations were statistically significant after weight adjustment. Despite differences by implant type, weight, or clinic location, drug concentrations compatible with contraceptive effect were attained within 24 h in users of LNG rod or of Norplant implants, insofar as all women had levonorgestrel concentrations above 250 pg/mL at the 24-h sample.
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Intracervical and fundal administration of levonorgestrel for contraception: endometrial thickness, patterns of bleeding, and persisting ovarian follicles. Fertil Steril 1997; 68:59-64. [PMID: 9207585 DOI: 10.1016/s0015-0282(97)81476-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE(S) To study the prevalence of persisting ovarian follicles and to assess the endometrial changes and patterns of vaginal bleeding over 1 year of use of a 20 micrograms/24 h levonorgestrel-releasing intracervical contraceptive device. DESIGN Prospective, randomized study. SETTING Two family planning clinics in Helsinki, Finland. PATIENT(S) Women requesting intrauterine hormonal contraception. INTERVENTION(S) Insertion of a levonorgestrel-releasing intracervical contraceptive device into the cervical canal (group 1, n = 151) or fundally into the uterine cavity (group 2, n = 147) for contraception. MAIN OUTCOME MEASURE(S) Transvaginal ultrasonography of the ovaries and endometrium at insertion and 3, 6, and 12 months after insertion. Data on bleeding were collected using menstrual diary cards. RESULTS Persisting ovarian follicles were found in < 8% of women. In both groups, the amount of endometrial tissue decreased significantly in 3 months. The incidence of amenorrhea during the 1st year was higher in the fundal insertion group. CONCLUSION(S) The number of persisting follicles was low. Follicles resolved within 6 to 8 weeks. No association was found between persisting follicles and problems of bleeding. Compared with intracervical insertion, fundal insertion resulted in more uniform endometrial suppression and fewer days of bleeding and spotting.
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Pharmacokinetics and pharmacodynamics of 7alpha-methyl-19-nortestosterone after intramuscular administration in healthy men. Hum Reprod 1997; 12:967-73. [PMID: 9194649 DOI: 10.1093/humrep/12.5.967] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
7alpha-Methyl-19-nortestosterone (MENT) is a potent synthetic androgen that is resistant to 5alpha-reductases and therefore less prone to over-stimulate the prostate. It is a good candidate for implant administration in long-term androgen replacement therapy for hypogonadal men or as part of a male contraceptive system. To investigate the pharmacokinetics of MENT after i.m. administration, single i.m. injections of 2, 4 or 8 mg of micronized MENT were given in aqueous suspension to 18 healthy men in two clinics. Blood was sampled frequently for 8 h and 1, 2, 3, 4 and 9 days after the injections. Serum MENT concentrations were determined by radioimmunoassay. Peak MENT concentrations were dose-dependent and were reached about 1-2 h after the injections. Doubling the dose of MENT resulted in an increase of 60% in peak serum MENT concentrations. The mean +/- SE clearance rate was 1790 +/- 140 l/day. The antigonadotrophic activity of MENT was investigated by giving six consecutive daily i.m. injections of 1, 2 or 4 mg of MENT to 24 healthy men in two clinics. Blood was sampled before each injection and up to 24 days after the last injection. Serum testosterone and gonadotrophin concentrations (determined by radioimmunoassay and fluoroimmunoassay respectively) decreased in a dose-dependent and statistically significant manner. The highest dose caused a 74% fall in testosterone, a 70% fall in luteinizing hormone, and a 57% fall in follicle stimulating hormone concentrations. MENT injections did not cause any side-effects. The results show that MENT is a potent antigonadotrophic agent in men.
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Abstract
The effects of short-term administration of the antiprogestin and antiglucocorticoid, mifepristone, have been well characterized. However, little is known about the effects of prolonged administration of mifepristone. We analyzed hormonal parameters in four female and three male patients with unresectable meningioma who were treated with mifepristone (200 mg/d) for 20 to 40 months. Serum samples were collected at monthly intervals approximately 24 hours following mifepristone ingestion. Serum thyrotropin (TSH), thyroxine (T4), free T4 (fT4), 3,5,3-triiodothyronine (T3), prolactin, and cortisol were analyzed by fluoroimmunoassay, and androstenedione by radioimmunoassay (RIA). Levels of mifepristone and its three most proximal metabolites were measured by high-performance liquid chromatography. TSH values increased significantly (P < .005, one-way ANOVA), with the most pronounced increase evident during the first 3 months of mifepristone treatment. Despite these changes, concentrations of TSH remained within the normal range throughout the treatment period. There were no significant changes in serum T4, fT4, T3 or prolactin; however, a transient decrease in serum T4 was noted at 2 to 3 months. Cortisol and androstenedione values increased significantly and in parallel (P < .05), suggesting an adrenal origin also for androstenedione. As during short-term administration, levels of mifepristone and its metabolites remained stable in the micromolar range. Individual levels of mifepristone were significantly correlated with those of TSH and cortisol. This suggests that the alterations in the pituitary-thyroid and -adrenal axes occurred in a concentration-dependent manner. It is concluded that long-term mifepristone treatment results in resetting of the pituitary-thyroid balance. As in the case with cortisol and androstenedione, it is likely that the alterations in serum TSH are due to the antiglucocorticoid properties of mifepristone. The clinical significance of these biochemical alterations in thyroid homeostasis remains to be determined. However, monitoring thyroid function during long-term mifepristone treatment appears to be warranted.
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Abstract
In a three-year randomized trial that included 398 women, blood samples were collected for the purpose of assaying levonorgestrel concentrations in women using a new two-rod contraceptive implant system or an earlier implant formulation, Norplant-2 implants. Sample collection was at 1, 3, 6, 9, and 12 months after placement and semiannually thereafter through three years. Resulting assays and analyses showed that levonorgestrel concentrations of each implant formulation decreased significantly with time after placement, with increasing body weight, and with ponderal index. In the third year, several measures indicated that concentrations of the contraceptive drug were higher in women using the LNG ROD implants than in users of the original formulation. No pregnancies occurred among women in either group in the three years. This study provides evidence that the minimum levonorgestrel concentration needed to protect against pregnancy is below 200 pg/ml, and possibly is below 175 pg/ml.
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Three-year follow-up of the use of a levonorgestrel-releasing intrauterine system in hormone replacement therapy. Acta Obstet Gynecol Scand 1997; 76:145-50. [PMID: 9049288 DOI: 10.3109/00016349709050071] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND The efficacy of a levonorgestrel-releasing intrauterine system in opposing endometrial proliferation and in preventing bleeding was studied in peri- and postmenopausal women receiving estrogen replacement therapy. METHODS This was an open, non-controlled follow-up study of the use of a levonorgestrel-releasing intrauterine system during continuous estrogen replacement therapy carried out by using oral, transdermal or subdermal estradiol. The efficacy of the progestin therapy was evaluated by transvaginal ultrasonography and by examination of endometrial biopsy samples taken 20 months (mean, range 17 - 22; first evaluation) and 34 months (mean, range 31 - 38 months; second evaluation) after insertion of the levonorgestrel-releasing intrauterine system, and by studying patterns of bleeding. Twenty-five women participated in the first evaluation, and 29 in the second. RESULTS Seventy-six percent of the women were amenorrheic at the first evaluation, and 79% at the second evaluation. Others had spotting for 1-2 days monthly or less often. The mean time until amenorrhea was reached was 6 months (range 2-13 months) after insertion of the levonorgestrel-releasing intrauterine system. The median endometrial thickness assessed by ultrasound was 2 mm at both evaluations. No signs of proliferation were observed in any of the endometrial samples. CONCLUSIONS Local progestin delivery via a levonorgestrel-releasing intrauterine system was effective in suppressing the endometrium and in eliminating bleeding in women receiving estrogen replacement therapy, and the intrauterine progestin therapy was also well accepted.
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Selection and performance of the levonorgestrel-releasing intrauterine system. ACTA OBSTETRICIA ET GYNECOLOGICA SCANDINAVICA. SUPPLEMENT 1997; 164:69-74. [PMID: 9225643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The levonorgestrel-releasing intrauterine system (LNg IUS) is a hormonal contraceptive that is used in the uterine cavity. To determine whether the reasons for choosing LNg IUS vs. copperreleasing intrauterine devices (Cu IUDs) differ and whether their performances are comparable, we carried out a retrospective study in Finland during the first years of LNg IUS use. METHODS Gynecological and contraceptive histories of 626 LNg IUS and 626 Cu IUD users and the performance of the device were reviewed from patient records. RESULTS Women who accepted the LNg IUS were more likely than Cu IUD acceptors to have a history of menstrual bleeding of 6 days or more (44.4% vs. 28.4%), heavy bleeding (44.8% vs. 8.4%) and moderate or severe dysmenorrhea (15.9% vs. 7.5%). In both groups, 70% of the women had used Cu IUDs earlier. However, the LNg IUS acceptors had had more side effects during previous use of CU IUDs (58.2% vs. 28.8%). They also reported more side effects that resulted in discontinuation of a previous Cu IUD (39.4% vs. 10.1%). However, the 12-month life-table continuation rates of 80.6 (SE 1.9)% vs. 83.4 (SE 1.8)% were alike. Cu IUD users discontinued the current method more often because of problems of bleeding and unwanted pregnancy. Among those women who had previously discontinued a hormonal method because of hormonal side effects, there were no differences in the continuation rates of the two groups. CONCLUSIONS LNg IUS can be successfully used by women who cannot use a CU IUD or who have experienced hormonal side effects with oral contraceptives.
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F163 Intrauterine progestin therapy in HRT: Results of a four-year follow-up study. Maturitas 1996. [DOI: 10.1016/s0378-5122(97)81126-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Detailed analysis of menstrual bleeding patterns after postmenstrual and postabortal insertion of a copper IUD or a levonorgestrel-releasing intrauterine system. Contraception 1996; 54:201-8. [PMID: 8922872 DOI: 10.1016/s0010-7824(96)00189-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Detailed information on the menstrual bleeding patterns in users of copper-releasing intrauterine devices (IUDs) and levonorgestrel-releasing intrauterine systems (IUSs) is lacking. Even less is known about the menstrual bleeding patterns associated with postabortal insertion of IUDs. We postulated that the scarcity of IUD studies including detailed analysis of bleeding could be a result of the lack of an easy-to-use computer program designed for this purpose. We therefore developed a set of graphical user interface (Windows) programs for entering, editing, and analyzing menstrual diary data. With these programs, we reanalyzed the menstrual diaries of the subjects of one of the hospital clinics that participated in a previous multicenter study comparing copper IUDs and LNg IUSs. The group included patients who had the IUD inserted postabortally. Copper IUD users had patterns of bleeding that were stable over time, and clearly more bleeding than LNg IUS users, many of whom had either infrequent bleeding, bleeding completely replaced by regularly occurring spotting, or amenorrhea. Postabortal insertion of LNg IUSs was associated with slightly better patterns of bleeding than postmenstrual insertion. Detailed statistics on bleeding help clinicians in counseling patients regarding these methods. The statistics permit assumptions to be made about the probabilities of specific menstrual disturbances and their changes over time.
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Abstract
Relatively low doses of the antiprogestin mifepristone (RU 486) have recently proven to be efficient for a variety of possible clinical uses of the drug. However, the pharmacokinetics after low single oral doses have not been characterized. We evaluated the pharmacokinetics of mifepristone following single ingestion of 2 and 25 mg in five women as well as repeated ingestion of 8 mg in two women. Maximal serum concentrations were reached rapidly (within 0.5-2 h) with all doses used. Serum mifepristone concentrations were proportional to the oral doses taken. The mean (+/- SD) areas under the concentration curves (AUCs) (0-24 h) were 1134 (+/- 144), 4846 (+/- 64), and 17,015 (+/- 4,421) h x ng/mL following 2, 8, and 25 mg doses, respectively. No cumulative increases in serum concentrations were detected with prolonged daily administration of 8 mg of mifepristone. The study subjects appeared to vary in their ability to metabolize mifepristone, as two different half-lives (t1/2) emerged after both 2 and 25 mg single doses (24.2 +/- 0.6 [SD] h for three subjects; and 44.4 +/- 1.8 [SD] h for two subjects). We conclude that within the dose range of 2-25 mg/day, the pharmacokinetics of mifepristone are linear, unlike those seen following ingestion of higher daily doses. Keeping in mind previously published data on the biological effects of low dose mifepristone administration, these data infer that certain effects of the drug, such as inhibition of ovulation, might be achieved at serum concentrations of approximately 100 ng/mL.
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MESH Headings
- Abortifacient Agents, Steroidal/administration & dosage
- Abortifacient Agents, Steroidal/blood
- Abortifacient Agents, Steroidal/pharmacokinetics
- Administration, Oral
- Adult
- Contraceptives, Oral, Synthetic/administration & dosage
- Contraceptives, Oral, Synthetic/blood
- Contraceptives, Oral, Synthetic/pharmacokinetics
- Dose-Response Relationship, Drug
- Female
- Half-Life
- Humans
- Mifepristone/administration & dosage
- Mifepristone/blood
- Mifepristone/pharmacokinetics
- Time Factors
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A 12-month comparative clinical investigation of a levonorgestrel-releasing intracervical device situated in the uterine cavity or cervical canal. Contraception 1996; 54:187-92. [PMID: 8899261 DOI: 10.1016/s0010-7824(96)00175-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A randomized study was performed in two clinics in order to compare the efficacy, safety and acceptability of a new model of a levonorgestrel-releasing intracervical device situated either in the cervical canal (group I) or in the uterine cavity (group II). Group I included 151 women (age 18-43) and group II, 147 women (age 19-43). The number of nulliparous women was 145. The total expulsion rate was 9.1%. The expulsion rate was lower among nulliparous women (4.8%) than among parous women (13.1%). There was also a significant difference in the expulsion rates between the two clinics. Two pregnancies occurred in both groups and two of these were ectopic, one in each group. The other two occurred after unnoticed expulsion. These figures give 12-month cumulative pregnancy rates of 1.3% and 1.4% in groups I and II, respectively. Total infection rate was 0.3%. The continuation rates were 82.1% in group I and 85.0% in group II after the first year. At three-month follow-up there were significantly fewer menstrual problems in group I than in group II (p = 0.0266). It is concluded that expulsion is still a problem with a small device but it may be diminished by intrauterine insertion and by selecting the users carefully.
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Effects of a sequential regimen of mifepristone-medroxyprogesterone acetate on ovarian function, endometrial development and hormonal parameters. Contraception 1996; 54:79-86. [PMID: 8842583 DOI: 10.1016/0010-7824(96)00138-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The efficacy of a low dose of mifepristone, 5 mg/day for the first 15 days of the menstrual cycle, followed by medroxy-progesterone acetate (MPA), 10 mg/day for the next 13 days, for inhibiting ovulation was assessed in ten volunteers who were treated for three successive cycles. Hormonal determinations in blood and urine samples, ovarian ultrasonography and an endometrial biopsy taken on day 21-24 of the third treatment cycle were used to monitor the cycles. Ovulation was confirmed in 11 of the 30 treated cycles and, in these 11, the LH peak and follicular rupture occurred during MPA treatment periods. Out of 19 anovulatory cycles, 16 had no increase in progesterone levels and another 3 developed a luteinized unruptured follicle. Progestin administration induced secretory changes in the endometrium, but irregular or delayed development was found. Regular withdrawal bleeding occurred in all subjects. These data indicate that the sequential regimen can suppress ovulation while maintaining regular bleeding but increased efficacy is needed for phase II clinical trials.
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Abstract
The antiprogestin RU 486 has been proposed for use as a contraceptive because it disturbs folliculogenesis and inhibits ovulation when given continuously. In order to achieve regular and predictable withdrawal bleeding and to counteract the continuous influence of estrogen on the endometrium, a sequential, cyclic progestin regimen has been added. The drawback has been the frequent rise in the concentration of serum P, suggesting ovulation. The present pilot study with three subjects was carried out to test whether simultaneous administration of RU 486 and progestin during the second half of the cycle would eliminate the rise in serum P concentrations. Based on elevated serum P values, five of the seven cycles were apparently ovulatory. RU 486 alone, when given throughout the cycle at a dose of 8 mg per day without added progestin, resulted in anovulatory cycles, but the lengths of these cycles were prolonged. We conclude that both simultaneous and sequential cyclic co-administration of progestin with RU 486 abolishes the antiovulatory action of RU 486. This decreases the possibility of using antiprogestins in non-estrogenic contraceptive regimens (unless contraceptive effects of RU 486 exist at the endometrial level).
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Endometrial response to hormone replacement therapy as assessed by expression of insulin-like growth factor-binding protein-1 in the endometrium. Fertil Steril 1996; 65:776-82. [PMID: 8654638 DOI: 10.1016/s0015-0282(16)58213-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE To assess endometrial response to parenteral levonorgestrel in hormone replacement therapy by means of morphological criteria and immunohistochemical staining of insulin-like growth factor-binding protein-1 (IGFBP-1). DESIGN Endometrial samples were collected from 35 postmenopausal women after 12 to 22 months of continuous combined estrogen-progestin therapy. All subjects were treated with parenteral progestin. A group of 8 women was treated with a subdermal levonorgestrel-releasing implant, and 27 women had a levonorgestrel-releasing intrauterine device (IUD). Sections of formalin-fixed paraffin-embedded biopsies were used for immunohistochemistry and after hematoxylin-eosin staining for routine histologic examination. RESULTS Atrophic epithelium with pronounced decidual reaction in the stroma was detected by histologic examination in all endometrial samples obtained from 27 women treated with the levonorgestrel-releasing IUD. In contrast, the endometrium was proliferative in seven of eight (87.5 percent) biopsies obtained from women treated with the levonorgestrel-releasing implant. Immunoreactive IGFBP-1 was detected in decidualized stromal cells in all endometrial samples obtained during intrauterine levonorgestrel therapy, whereas only one of eight samples obtained from women treated with subdermal levonorgestrel exhibited weak staining for IGFBP-1. CONCLUSIONS Our data show that both the morphological and biochemical response of post- menopausal endometrium to parenteral levonorgestrel was strikingly different, depending on the route of progestin administration, and that the decidual reaction and epithelial atrophy induced by intrauterine levonorgestrel were associated with expression IGFBP-1 in decidualized stromal cells.
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[Patients in menopause]. DUODECIM; LAAKETIETEELLINEN AIKAKAUSKIRJA 1996; 112:1031-2. [PMID: 10593001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
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The effect of local intrauterine levonorgestrel administration on endometrial thickness and uterine blood circulation. Hum Reprod 1995; 10:2390-4. [PMID: 8530672 DOI: 10.1093/oxfordjournals.humrep.a136305] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
To evaluate non-invasively the role of levonorgestrel releasing devices in direct contact with the endometrium on menstrual spotting and endometrium inactivation, we inserted levonorgestrel releasing devices (20 micrograms/24 h) either into the cervical canal or the uterine cavity of 30 fertile women. Both before insertion and over the following 3 months, we used transvaginal sonography to measure the endometrial thickness in 20 of the women and Doppler flow to measure the uterine blood flow in the remaining 10 women. The women were asked to keep records of menstrual bleeding and they gave blood samples for the measurement of serum oestradiol, progesterone and levonorgestrel. By 10 weeks after insertion there was a significant decrease in endometrial thickness in both groups. Intracervical levonorgestrel release allowed the endometrium to maintain cyclic changes, whereas direct intrauterine levonorgestrel release eliminated the cyclical changes. The total number of spotting days was significantly less (P = 0.0249) in the intracervical release group at 3 months; 1.2 +/- 0.6 versus 8.1 +/- 1.8 (mean +/- SE). There were no significant differences in hormone concentrations between the groups. The pulsatility index did not change significantly during the study. We concluded that the inactivation process of the endometrium can be monitored by transvaginal sonography and that locally administered levonorgestrel does not change circulatory conditions detectable by Doppler flow. Our results also suggest that the inactivation process of the endometrium is different between intracervical and intrauterine levonorgestrel administration and may explain the difference in the number of spotting days.
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Antiovulatory actions of RU 486: the pituitary is not the primary site of action in vivo. J Clin Endocrinol Metab 1995; 80:1859-68. [PMID: 7775633 DOI: 10.1210/jcem.80.6.7775633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Continuous administration of RU 486 impairs follicular development and inhibits ovulation in women. Yet, the mechanism of ovulation inhibition remains unknown. To characterize the mechanism(s) of ovulation inhibition, we studied six regularly menstruating cynomolgus monkeys for three consecutive (control-rest-treatment) cycles. Monkeys received 1 mg/kg.day RU 486 in between cycle days 2-22. Basal and GnRH-stimulated (1 and 50 micrograms GnRH, iv, 2 h apart) secretion of LH and FSH was assessed using serial blood samples (every 15 min for 12 h) collected on cycle day 10. Serum levels of estradiol (E2), progesterone (P4), RU 486, cortisol, LH, FSH, and PRL were analyzed by RIAs, the bioactivity of LH was assessed using a mouse Leydig cell assay. The mean cycle length was prolonged by RU 486 treatment from 31.8 to 69.8 days (P = 0.008). During RU 486 treatment, patterns of E2 secretion varied considerably; the mean +/- SD E2 level was 204 +/- 139 pmol/L. LH peaks and P4 profiles compatible with luteal function were seen only before resumption of menstruation. However, one monkey had an increase in P4 after the GnRH challenge-induced LH secretion. Basal levels of LH varied between suppressed and apparently normal values, whereas basal FSH seemed little affected by RU 486 treatment. In two monkeys with E2 secretion indicative of normal follicular development, minor peaks of LH, but no rises in serum P4, were seen. The ratio of bioactive/immunoactive LH was reduced in these monkeys during RU 486 treatment compared to that during the washout period of the treatment cycle. Surprisingly, the pituitary responsiveness to acute GnRH challenge was not affected by RU 486 administration. The individual levels of RU 486 were similar during the treatment period (mean, 40 nmol/L). A resumption of ovulatory cycles occurred when RU 486 concentrations were below 2.5 nmol/L. We conclude that in cynomolgus monkeys, inhibition of ovulation by RU 486 occurs mainly at the level of the hypothalamus, with possible additional effects on the granulosa cell function and alterations of LH bioactivity.
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Abstract
OBJECTIVE To compare the effects of intrauterine and subdermal administration of levonorgestrel on control of bleeding and on the endometrium in postmenopausal hormone replacement therapy. INTERVENTIONS Nineteen women started continuous oral E2 valerate therapy (2 mg daily) together with continuous parenteral progestin therapy. The subjects randomly received either a subdermal levonorgestrel-releasing implant (n = 9) or an intrauterine device (IUD) releasing levonorgestrel (n = 10). MAIN OUTCOME MEASURES Serum concentrations of estrone, E2, FSH, sex hormone-binding globulin (SHBG) and levonorgestrel were followed. Endometrial biopsies and transvaginal ultrasonography were used to evaluate the endometrium. The subjects kept daily records of bleeding. The observation time was 1 year. RESULTS Serum concentrations of the hormones mentioned above and SHBG were similar in both groups during the observation time, but the patterns of bleeding differed. In the IUD group there were 0.9 days (mean, range 0 to 4 days) of spotting and no days of bleeding during the last month of the follow-up year. In the implant group there were 8 days (mean, range 0 to 25 days) of spotting and 3.4 days (mean, range 0 to 14 days) of bleeding. In histological examination there was uniform atrophy in the endometrial samples from the IUD group, and a weak or absent progestin effect in the implant group. CONCLUSIONS In spite of similar serum levonorgestrel concentrations, local intrauterine administration of levonorgestrel resulted in better control of bleeding and in more effective endometrial suppression than subdermal administration.
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Effects of intermittent antiprogestin RU486 combined with cyclic medroxyprogesterone acetate on folliculogenesis and ovulation. Hum Reprod 1995; 10:287-92. [PMID: 7769050 DOI: 10.1093/oxfordjournals.humrep.a135929] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The results of several studies have suggested an inhibitory effect of the antiprogestin RU486 on late stages of folliculogenesis and ovulation. To assess the feasibility of using this property to inhibit ovulation without losing cycle control, an intermittent administration of RU486 alternated with medroxyprogesterone acetate (MPA) was tested in a phase I study. RU486 at a dose of 50 mg/day was given on menstrual cycle days 9-11 and 27-29, and 10 mg/day of MPA was given on cycle days 17-26 for three consecutive cycles to six Finnish and five Chilean women. Blood samples were collected two to three times a week for serum progesterone and oestradiol assays in three treatment cycles. One control cycle and one post-treatment recovery cycle were also monitored by serum samplings. Ultrasonography was carried out to measure follicular diameters in the treatment cycles. In 29 of 32 cycles, bleeding commenced within 3 days after the last MPA pill intake. Out of 32 treatment cycles, 20 were without luteal activity (serum progesterone < 9 nmol/l). Although 12 treatment cycles showed luteal activity (serum progesterone > or = 9 nmol/l), a clear rupture of a pre-ovulatory follicle > 15 mm, verified by ultrasonography, was seen in only one treatment cycle. During the treatment cycles with luteal activity (serum progesterone levels > or = 9 nmol/l), serum oestradiol concentrations were significantly higher on cycle days 9-18 and significantly lower at the end of the cycle compared with the cycles without luteal activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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Sustained-release estradiol implants and a levonorgestrel-releasing intrauterine device in hormone replacement therapy. Am J Obstet Gynecol 1995; 172:562-7. [PMID: 7856686 DOI: 10.1016/0002-9378(95)90573-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE Efficacy and acceptability of continuous combined parenteral hormone replacement consisting of subdermal estradiol delivery and intrauterine progestin delivery was studied. STUDY DESIGN Thirty-six volunteer postmenopausal women seeking treatment for climacteric symptoms participated in this open, randomized study. The subjects received either one or three subdermal implants with a controlled daily release of estradiol in vitro. Progestin therapy was carried out with a levonorgestrel-releasing intrauterine device. Climacteric symptoms and serum concentrations of estrone, estradiol, follicle-stimulating hormone, and sex hormone-binding globulin were followed up for 1 year. The subjects kept daily records of bleeding. RESULTS Serum estradiol concentrations with the set of three implants were stable during the follow-up period; the range of mean serum estradiol concentrations was 45 to 57 pg/ml. Four women, all from the group with one implant, discontinued the study after 6 months because of the return of climacteric symptoms. In spite of different daily estradiol doses, the patterns of bleeding were similar in both groups. At the end of the follow-up year 72% of the women had had no bleeding or spotting in the previous 3 months. CONCLUSION Our results suggest that by combining subdermal and intrauterine steroid delivery systems postmenopausal hormone replacement therapy can be carried out successfully without daily effort and with minimal or no bleeding.
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Abstract
The clinical performance and the in vivo release rate of a single 4-cm Nestorone subdermal implant were investigated. Implants manufactured by two different procedures were compared. Volunteers were 70 healthy women of proven fertility. Forty women provided blood samples twice a week in the pretreatment cycle and for 5-6 weeks at 6-month intervals during treatment. Additional control cycles (n = 31) were studied in 19 Copper T users. No pregnancy occurred in 1570 woman-months. Nestorone plasma levels (x +/- S.E.) declined from 112 +/- 8 to 86 +/- 3 pmol/L (Implant A) and from 145 +/- 8 to 57 +/- 5 pmol/L (Implant B) from the first to the 24th month. Progesterone levels were < 9.5 nmol/L in 166 (93%) of 178 blood samplings taken during treatment. Progesterone levels > 16 nmol/L were found in only 7 sampling periods (3.9%) in treated women and in 70 (98.6%) out of 71 control cycles. No ovulation occurred with Nestorone plasma levels above 105 pmol/L. No abnormal changes were observed in plasma lipoproteins or other clinical chemistry parameters during treatment. The implants were well tolerated. The most frequent complaint was the occurrence of irregular bleeding. Enlarged follicles found during pelvic examination in 8 subjects (11.4%) disappeared spontaneously in 10 days to 6 weeks. Implants were removed because of medical (n = 10, 14.3%) or personal reasons (n = 6, 8.6%) or at the 24th month of treatment (n = 54, 77.1%). The estimated average daily in vivo release rate of Nestorone was 45-50 micrograms/day. A single Nestorone subdermal implant affords efficient contraceptive protection during two years.
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Abstract
Parenterally administered ST 1435 (Nestorone) is highly potent for contraception, and ovulation can be inhibited with very low serum levels of ST 1435. Orally administered ST 1435 is ineffective in various laboratory animals, presumably due to extensive first-pass metabolism. Thus, ST 1435 has been proposed for lactational contraception, to be metabolized by the suckling infant. We have studied the metabolism of ST 1435 in female volunteers following oral (10 mg), intravenous (iv) (0.1 mg) and transdermal (4.5-9.0 mg) routes of ST 1435 administration. Preliminary studies using rats were performed to develop the methodology of high performance-liquid chromatography (HPLC) fractionation and ST 1435-RIA detection. Rat portal serum revealed 4 distinct peaks of immunoreactive material with the retention times (Rt's) of 7.5, 10, 14.5 and 17.5 min (ST 1435 = 10 min). In systemic serum, only the peak with the Rt of 7.5 min could be detected. Therefore, orally administered ST 1435 is very effectively metabolized by the rat liver; this also explains the previously observed lack of biological effects of oral ST 1435. Following oral administration of ST 1435 to two women, the Rt of the major peak was 10 min. The magnitude of the ST 1435 peak decreased rapidly, and at 24h following ingestion, no ST 1435 could be detected by this method. The t1/2 of ST 1435 was approximately 1-2h. In addition, two minor peaks with Rt's of 4.5 and 16 min could be detected with the ST 1435 RIA at 1-4h following oral ingestion. Competitive receptor binding assays using the human uterine progesterone receptors (hPR) revealed that the ST 1435 fraction exhibits strong binding affinity towards the hPR; thus, in the human, a small fraction of biologically active ST 1435 seems to escape from the first-pass metabolism following oral intake. Following iv and transdermal administration of ST 1435, the only detectable peak with ST 1435-RIA was that of ST 1435. Similar magnitude of the ST 1435 peaks following oral administration of 10 mg and iv administration of 0.1 mg indicated that the bioavailability of ST 1435 is low. These data seem to confirm the suspicion that orally administered ST 1435 is also rapidly metabolized in the human, therefore encouraging further evaluation of ST 1435 during lactation. However, the rapid metabolism seen after oral intake can be successfully circumvented by sustained parenteral administration of ST 1435.
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