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Featured researches published by Peter Sjöblom.


Human Genetics | 1999

A high degree of aneuploidy in frozen-thawed human preimplantation embryos

Erik Iwarsson; Monalill Lundqvist; José Inzunza; Lars Ährlund-Richter; Peter Sjöblom; Örjan Lundkvist; Niklas Simberg; Magnus Nordenskjöld; Elisabeth Blennow

Abstract We have studied the chromosomal content in 68 normally fertilised freeze-thawed human embryos of good morphology from 34 patients with an average maternal age of 32,6 years. Forty embryos showed post-thaw cellular division and twenty-eight post-thaw cleavage arrest. After spreading of the embryos on microscope slides, analysis of chromosomes X, Y, 15, 16, 17 and 18 was performed using two rounds of fluorescent in situ hybridisation (FISH). According to the results, the embryos were divided into four groups: (I) normal, all nuclei uniformly diploid, (II) diploid mosaics, normal diploid blastomeres in combination with abnormal blastomeres, (III) abnormal, all nuclei abnormal, (IV) chaotic, the chromosome constitution varies randomly from cell to cell. Approximately 25% of the embryos had normal number of the chromosomes tested, while the majority of the embryos were abnormal. Most of the abnormal embryos were diploid mosaics (57%). This was true for the embryos showing cleavage division as well as the embryos showing cleavage arrest. Our data show a slightly higher incidence of abnormal embryos compared to those obtained with FISH in non-cryopreserved embryos and confirm that the majority of preimplantation embryos fertilised in vitro contain abnormal blastomeres. The results, mechanisms, significance and implications are discussed.


Journal of Assisted Reproduction and Genetics | 1998

Outcome of IVF in Patients with Endometriosis in Comparison with Tubal-Factor Infertility

Annica Bergendal; Sophie Naffah; Christina Nagy; Agneta Bergqvist; Peter Sjöblom; Torbjörn Hillensjö

Purpose:The aim of this retrospective study was to compare the outcome of in vitro fertilization and embryo transfer in women with endometriosis and a control group with tubal-factor infertility.Methods:Forty-eight patients with endometriosis underwent 65 cycles of in vitro fertilization and embryo transfer at Huddinge University Hospital. The matched control group with tubal-factor infertility consisted of 98 cycles in 98 patients. These groups were retrospectively analyzed regarding stimulation, fertilization, embryo development, implantation, and pregnancy outcome.Results:The fertilization rate was significantly lower in women with endometriosis, but the cleavage, implantation, and pregnancy rates did not differ.Conclusions:Our results show that women with endometriosis have a lower fertilization rate compared with women with tubal-factor infertility. However, once the oocyte is fertilized, it seems that the preembryo has a normal chance of implantation, leading to similar pregnancy rates.


Prenatal Diagnosis | 2000

Highly abnormal cleavage divisions in preimplantation embryos from translocation carriers

Erik Iwarsson; Helena Malmgren; José Inzunza; Lars Ährlund-Richter; Peter Sjöblom; Björn Rosenlund; Margareta Fridström; Outi Hovatta; Magnus Nordenskjöld; Elisabeth Blennow

We have developed preimplantation genetic diagnosis (PGD) for carriers of chromosomal abnormalities using fluorescent in situ hybridisation (FISH). Here we present the detailed analysis of 64 biopsied, normally developing embryos obtained from four Robertsonian and three reciprocal translocation carriers in 11 treatment cycles of which four resulted in normal pregnancies (three simplex, one duplex). In order to investigate the degree of mosaicism and segregation mode in the embryos, the primary analysis of the biopsied cells was extended with the analysis of all cells from the non‐transferred embryos. The analysis also included a second hybridisation with two additional probes, not involved in the translocation (chromosomes 1 and 9), in order to investigate the overall degree of mosaicism. Seventeen out of 64 analysed embryos were balanced for the chromosomes involved in the translocation and 14 of these were transferred. Forty‐seven out of 64 embryos (73%) were mosaic regarding the chromosomes involved in the translocation and alternate segregation mode was the most common mode of segregation. Moreover, we have found a higher degree of mosaicism for the chromosomes involved in translocations as compared to control chromosomes. This difference was more pronounced for the embryos from reciprocal translocation carriers. The results, mechanisms, significance and implications of our findings are discussed. Copyright


Hypertension in Pregnancy | 1999

Are Women with Polycystic Ovary Syndrome at an Increased Risk of Pregnancy-Induced Hypertension and/or Preeclampsia?

Margareta Fridström; Henry Nisell; Peter Sjöblom; Torbjörn Hillensjö

OBJECTIVE To study whether there is an increased risk of glucose intolerance and hypertensive complications during pregnancy in women with polycystic ovary syndrome (PCOS) and if there is an adverse pregnancy outcome. METHODS In a retrospective case-control study, pregnancies and neonatal outcome were compared in 33 women with PCOS and 66 women without PCOS. The women were treated at Huddinge University Hospital; antenatal care was given at associated outpatient units. MAIN OUTCOME MEASURES Blood glucose and blood pressure during the different trimesters. Pregnancy outcome in terms of gestational length, birth weight, and need for neonatal intensive care. RESULTS No significant differences were found in blood glucose levels between the groups. There were also no differences in blood pressure during the first and second trimester. However, during the third trimester and labor, the PCOS group had a significantly higher blood pressure than the control group. Apart from a tendency toward reduced growth of twins in PCOS mothers, the babies were healthy, overall, with few problems in the neonatal period. CONCLUSIONS No major differences with regard to perinatal outcome in pregnant women with and without PCOS were found. An increased risk of hypertensive disorders in the third trimester and during labor was demonstrated in the PCOS group. This suggests that in the antenatal care of women with PCOS, attention should focus on blood pressure in order to reduce the risks of morbidity associated with hypertension.


Gynecologic and Obstetric Investigation | 2000

Production of Interleukins 1β, 6 and 8 and Tumor Necrosis Factor Alpha in Separated and Cultured Endometrial and Endometriotic Stromal and Epithelial Cells

Agneta Bergqvist; Hedieh Nejaty; Berit Fröysa; Christine Bruse; Magdalena Carlberg; Peter Sjöblom; Olle Söder

The production of IL-1β, IL-6, IL-8 and TNF-α was studied in short-time culture of separated stromal and epithelial cells. The cytokine secretion into culture medium was analyzed using immunoassay to evaluate the cytokine protein levels and bioassay to assess the bioactivity of the cytokines. Tissue samples of endometrium and ovarian endometriomas were obtained from 4 patients operated on for clinical reasons. Only IL-8 was found in all samples. IL-1β and TNF-α were detected in the culture medium from most stromal cell samples, but in fewer media from epithelial cell samples. IL-6 was measurable in a few medium samples. Few of the samples displayed a bioactivity. There was no obvious difference between endometrium and endometriotic cell samples besides the production of IL-8 that seems to be lower in endometriotic tissue.


American Journal of Obstetrics and Gynecology | 1989

Serial human chorionic gonadotropin determinations by fluoroimmunoassay for differentiation between intrauterine and ectopic gestation

Bo Lindblom; Mats Hahlin; Peter Sjöblom

A new means for differentiation between ectopic and early intrauterine pregnancy--the human chorionic gonadotropin score--is described. The score relates the rate of serum hCG rise per day to the initial human chorionic gonadotropin level. The positive predictive value for ectopic pregnancy was 94.7%, based on human chorionic gonadotropin scores from 41 women with increasing human chorionic gonadotropin levels in the range of 10 to 4000 IU/L. The method may be useful for identification of ectopic pregnancy in a category of women in whom ultrasonography is of limited diagnostic value.


Journal of Assisted Reproduction and Genetics | 2002

No Decline in Semen Quality Among Potential Sperm Donors in Sydney, Australia, Between 1983 and 2001

Michael F. Costello; Peter Sjöblom; Youala Haddad; Stephen J. Steigrad; Edward G. Bosch

AbstractPurpose: To determine whether the quality of semen has changed over time in men screened for semen donation. Methods: All 448 men volunteering for semen donation between 1983 and 2001 at a donor insemination clinic in Sydney, Australia, were included in this longitudinal single centre observational analysis of semen parameters. There was no selection for fertility or marital status but all volunteers had to be aged between 18 and 40 years. Results: There was no change in the total sperm count during the study period (r = 0.065, P = 0.17) using a linear regression model. The ejaculate volume did not change (r = 0.002, P = 0.97), while an increase in sperm motility was seen (Spearman R = 0.194, P < 0.001). Conclusion: The semen quality of volunteers for sperm donation presenting to our donor insemination clinic in Sydney between 1983 and 2001 has not declined.


Prenatal Diagnosis | 1998

Application of single-needle blastomere biopsy in human preimplantation genetic diagnosis

José Inzunza; Erik Iwarsson; Margareta Fridström; Björn Rosenlund; Peter Sjöblom; Torbjörn Hillensjö; Elisabeth Blennow; B. Jones; Magnus Nordenskjöld; I. Ährlund-Richter

We have tested and subsequently successfully applied a single‐needle approach to obtain blastomere biopsies from human preimplantation embryos for preimplantation genetic diagnosis (PGD).


Acta Obstetricia et Gynecologica Scandinavica | 1995

Human chorionic gonadotropin patterns in early pregnancy after assisted reproduction

Margareta Fridström; Leena Garoff; Peter Sjöblom; Torbjörn Hillensjö

Background. Assisted reproduction implies increased risks of pathological pregnancy, necessitating close follow up of early pregnancy. The use of serum hCG levels two and three weeks after embryo transfer for prediction of pregnancy outcome after in vitro fertilization‐embryo transfer (IVF/ET) or gamete intrafallopian transfer (GIFT) was evaluated.


Journal of Assisted Reproduction and Genetics | 2006

Power doppler ultrasound assessment of the relationship between age and ovarian perifollicular blood flow in women undergoing in vitro fertilization treatment

Michael F. Costello; Sanu M. Shrestha; Peter Sjöblom; Glen McNally; Michael Bennett; Stephen J. Steigrad; Graeme J. Hughes

Purpose: To examine the relationship between age and ovarian perifollicular blood flow (PFBF) in women undergoing IVF.Methods: Serial transvaginal power Doppler ultrasound (PDU) scans to assess ovarian PFBF were performed prospectively throughout the follicular phase of ovarian stimulation in women undergoing IVF. The ultrasound assessment days were categorized according to day of hCG trigger.Results: A total of 1050 ovarian follicles from 34 women undergoing one IVF treatment cycle were used for data analysis. The median age of the women was 38.5 years, ranging from 28 years to 44 years. There was a significant negative correlation between age and ovarian PFBF on the day of hCG trigger or trigger day minus 1, but not beforehand during the follicular phase.Conclusions: There was a significant negative correlation between age and ovarian PFBF in women undergoing IVF which was only observed very late in the follicular phase of ovarian stimulation.

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Bo Lindblom

Sahlgrenska University Hospital

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Michael F. Costello

University of New South Wales

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Erik Iwarsson

Karolinska University Hospital

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Magnus Nordenskjöld

Karolinska University Hospital

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Mats Hahlin

Sahlgrenska University Hospital

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