Karl Gösta Nygren

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BACKGROUND The possible excess of congenital malformations in infants born after in vitro fertilization (IVF) has been much discussed in the literature, with controversial conclusions. This population based study is aimed at analyzing the presence of congenital malformations in a large group of infants born after IVF and to compare malformation risk both(More)
BACKGROUND The risk for congenital malformations is increased in infants born after in vitro fertilization (IVF). Some specific malformations appear to be more affected than others. METHODS The presence of congenital malformations in 15,570 infants born after IVF with an embryo transfer between April 1, 2001, and the end of 2006 were compared with all(More)
OBJECTIVE To study long-term morbidity among children conceived by IVF. DESIGN A register study in Sweden of IVF infants compared with all infants born. SETTING National health registers. PATIENT(S) More than 16,000 children born after IVF (30% of them after intracytoplasmic sperm injection) were studied with national health registers. MAIN OUTCOME(More)
BACKGROUND Deliveries among women who had an in vitro fertilization (IVF) are characterized by increased risks for both the mother and the infant/child. Part of these effects may be due to maternal characteristics. METHODS Using reports from all clinics performing IVF in Sweden, 12 186 women who gave birth after such procedures were identified (13 261(More)
OBJECTIVE To compare neonatal outcome of blastocyst and cleavage stage embryo transfers after IVF. DESIGN Register study. SETTING Births recorded in the Swedish Medical Birth Register after IVF performed, 2002-2006. PATIENT(S) Treatments reported from all Swedish IVF clinics. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Some neonatal(More)
OBJECTIVE To compare infant outcome after different IVF techniques. DESIGN A register study in Sweden of IVF infants compared with all infants born. SETTING National health registers. PATIENT(S) We studied 16,280 IVF infants, 30% of whom were conceived by intracytoplasmic sperm injection (ICSI). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S)(More)
OBJECTIVES Studies conducted so far have found no statistically significant increased risk for cancer among children who are born after in vitro fertilization (IVF). METHODS We followed 26,692 children who were born after IVF during the years 1982-2005 by using the Swedish Cancer Register and compared the number of children who had cancer and were born(More)
STUDY QUESTIONS What are the risks of adverse outcomes in singletons born after frozen-thawed embryo transfer (FET)? SUMMARY ANSWER Singletons born after FET have a better perinatal outcome compared with singletons born after fresh IVF and ICSI as regards low birthweight (LBW) and preterm birth (PTB), but a worse perinatal outcome compared with singletons(More)
Modified natural cycle IVF (mnc-IVF) or mild IVF (m-IVF) was offered to selected patients between 1996 and 2007; 43 patients during 129 cycles were treated with mnc-IVF and 145 couples during 250 cycles were treated with m-IVF. Comparison with outcome from conventional IVF cycles during the same time period and in the same clinic was performed. Although(More)
BACKGROUND Various outcomes have been described during pregnancy and among infants born to women after in vitro fertilisation (IVF) treatments. This mini-review summarises recent population-based Swedish studies about the short- and long-term effects of IVF on the infant and child, and also comments on disturbances of pregnancies and deliveries occurring(More)