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Per Sundström

Publications and source records attributed to Per Sundström.

5 recordsLinked to original sources
PubMed2005

Nuclear status of four-cell preembryos predicts implantation potential in in vitro fertilization treatment cycles.

OBJECTIVE: To assess the value of routine screening of nuclear status of day-2 four-cell preembryos for single embryo transfer (SET) in predicting implantation. DESIGN: Retrospective analysis. SETTING: Private IVF unit. PATIENT(S): A total of 1,985 fresh embryo transfers on day 2 or day 3 were performed from January 2002 to November 2004. In 1,295 (65.2%) of these transfers, SET was performed. All day-2 four-cell preembryos transferred in SET cycles (n = 861) were analyzed retrospectively for outcome in terms of implantation rate and its relation to the number of visible mononucleate blastomeres (MNBs), the degree of fragmentation, and equality of blastomeres. INTERVENTION(S): Light microscopic evaluation of preembryos before transfer on day 2. MAIN OUTCOME MEASURE(S): Implantation rate. RESULT(S): The number of MNBs was found to be related to implantation, whereas blastomere equality and rate of embryo fragmentation were not. The implantation rate was statistically significantly higher in cycles where a four-cell preembryo with four MNBs was transferred than after transfer of a four-cell preembryo with zero to three MNBs (42% versus 22%). In a logistic regression analysis, nucleation of all blastomeres was the only morphologic parameter that was associated with the implantation rate. CONCLUSION(S): Evaluation of nuclear status of four-cell preembryos is important in predicting implantation potential. Visualization of four MNBs in a four-cell preembryo predicted a statistically significant higher implantation rate than in cases where not all four blastomeres were mononucleate.

Adult↗
PubMed2004

Would legislation imposing single embryo transfer be a feasible way to reduce the rate of multiple pregnancies after IVF treatment?

Due to increased maternal and fetal risks, there is a strong opinion in favor of single embryo transfer (SET) in order to reduce the high multiple pregnancy rate after IVF. We have evaluated the effects on pregnancy rate and twinning of recent Swedish legislation on SET. The study comprised three embryo transfer (ET) periods: period I, autumn 2001-spring 2002 (n=609), with a double embryo transfer (DET) policy; period II, autumn 2002 (n=320), a transitional period; and period III, January-September 2003 (n=433), with a SET policy. During the three periods, the SET rates were 25.1, 55.5 and 72.7%, respectively (Kruskal-Wallis test P<0.0001). There was no difference in clinical pregnancy rates (33.3, 32.8 and 37.4%, respectively) (P=0.4), but the twinning rate was significantly lower in the third period (6.2 versus 22.6% in period I and 16.3% in period II) (P<0.005). After introducing a SET policy, the expected decline of twinning was met at an unchanged clinical pregnancy rate. Thus, the SET legislation had no negative consequences for the couples. On the contrary, the lower rate of twinning is expected to reduce the severity and rate of pregnancy complications after IVF. Whether legislation or voluntary SET is the most feasible way to proceed, in order to reduce the multiple pregnancy rates after IVF, can be debated.

Adult↗
PubMed2004

[Good results of single embryo transfer after in vitro fertilization. The first follow-up report after the introduction of a new regulatory guideline].

A legislation was issued by the Swedish National Board of Health from January 1st 2003, stating mandatory single embryo transfer (SET) after in vitro fertilization. Two embryos may, however, be transferred if the risk for twin pregnancy can be considered to be low. Over a period of one year, the rate of SET in our clinic was increased from 25% to 71% of all fresh embryo transfers. In spite of this, we maintained the overall viable pregnancy rate (34%). The twin pregnancy rate, on the other hand, decreased from 23% to 6%. The quality of the transferred embryo(s) was an important factor for success. Transfer of two embryos of good quality did not increase the pregnancy rate compared to transfer of one embryo of good quality but increased the risk for twin pregnancy only.

Embryo Transfer↗