Avtor/Urednik		Korošec, Sara; Tomaževič, T; Virant-Klun, I; Meden-Vrtovec, H
Naslov		Characteristics of twin-prone women undergoing in vitro fertilization and double blastocyst transfer - the Slovenian experience
Tip		članek
Vir		Geburtshilfe Frauenheilkd
Vol. in št.		Letnik 67
Leto izdaje		2007
Obseg		str. 1109-13
Jezik		eng
Abstrakt		Purpose: To identify a subgroup of twin-prone women undergoing in vitro fertilization (IVF) with blastocyst transfer. Materials and methods of investigation: In a retrospective cohort study, 2539 IVF cycles (7334 classical IVF and 1205 intracytopfasmic sperm injection (ICSI) cycles) in 1641 couples in the 3-year period were included. The cycles resulting in blastocysts were analysed in terms of female age, number of IVF attempts, infertility indication, number of developed blastocysts, and pregnancy, twin pregnancy and abortion rates. Results: Blastocysts developed in 52% of cycles. The pregnancy rate per blastocyst transfer was 43% and the twin rate per pregnancy 20%. We found a negative correlation between twin pregnancy rates, female age and number of IVF attempts, and a positive correlation between twin pregnancy rates and number of developed blastocysts. ICSI compromised blastocyst development without directly affecting pregnancy and twin pregnancy rates. Significantly higher twin pregnancy rates (39% per pregnancy) were observed in women younger than 34 years who had 3 or more developed blastocysts. Discussion, conclusions: The subgroup of twinprone women undergoing blastocyst transfer is characterized by age < 34 years, and number of developed blastocysts >-3. Elective single blastocyst transfer in these selected women would hypothetically reduce twin pregnancy rates from 20 to 8% per pregnancy.
Deskriptorji		FERTILIZATION IN VITRO EMBRYO TRANSFER OVULATION INDUCTION PREGNANCY, MULTIPLE TWINS GONADOTROPINS, CHORIONIC MATERNAL AGE