Professor Andersen's major research contributions have been in ovarian endocrinology, oocyte maturation, cryopreservation of gonadal tissue, human embryonic stem cells and development of new principles for ovarian stimulation including the introduction of the agonist trigger and novel approaches to luteal phase support.
He has published more than 300 peer-reviewed scientific papers. He is a much-requested international lecturer and is currently giving around 30 international lectures annually. His current H-index is 65 with more than 14.000 citations. His is currently chief editor on the Reproduction section in Frontiers in Endocrinology.