Skip to main content
. 2021 Jun 24;11(6):e051058. doi: 10.1136/bmjopen-2021-051058

Table 3.

Secondary outcomes

Outcome Assessment
Fertilisation Fertilisation rate per aspirated oocyte retrieved (16–20 hours after IVF/ICSI) defined as the appearance of 2 pronuclei
Cycles with total fertilisation failure
Embryo data Embryo quality (ie, good quality blastocysts according to Gardner classification)
Embryo time-lapse kinetics including cleavage patterns
Embryo utilisation rate (number of transferred + cryopreserved embryos per number of 2 PN zygotes)
Freeze Number of frozen blastocysts (time frame: up to 6 days after oocyte pick up (OPU))
Pregnancy Positive pregnancy test (positive urine or serum hCG 11-21 days after embryo transfer)
Multiple pregnancy (period: up to 12 weeks after embryo transfer). Number of intrauterine gestations
Ongoing pregnancy per transfer (fetal heartbeat on ultrasound in gestational week 7–8)
Miscarriage Pregnancy loss rate (period: up to 12 weeks after embryo transfer)
Biochemical pregnancies (positive urine or serum hCG 11-21 days after embryo transfer without any clinical signs of intra- or extrauterine pregnancy)
Ectopic pregnancy/PUL
Birth/offspring All live birth episodes (all live births from the study oocyte collection (including second and further live births)
Preterm delivery (delivery at gestational week 22–36+6)
Birth weight/weight for gestational age
Congenital anomaly diagnosed at birth

ICSI, intracytoplasmic sperm injection; IVF, in vitro fertilisation; OPU, oocyte pick up; PN, pronuclei; PUL, pregnancy of unknown location.