Tamminga, P.

mortality perinatal study children health birth singleton perinatal mortality ivf twins outcome pregnancy netherland ivf singletons risk factors embryo transfer embryo transfer factor sample strategy health problems health outcomes registry centre reprod hospital result analysis data collection information problem cost-effectiveness embryo transfer strategies dutch perinatal mortality risk department model group maastricht university university prevalence parent collection det strategies anomaly decline number dutch perinatal mortality twinsing study treatment patient van heesch 18- year ivf treatment base sample research pediatrics maastricht twinsing preterm child gestation heesch birth weight risk groups change complication category outcome data mortality risk markov model evers jl health status ethnicity figure measure obstetric women death hemminki e