Yuan An et al, J Assist Reprod Genet. 2013 Jan; 30(1): 35–41
264 women undergoing IVF were tested periodically for cortisol and noradrenaline status. Additionally they completed assays to determine anxiety and depression. Lower levels of the stress hormones were found in women who were successful in conceiving and having a live birth. This is likely one of the mechanisms whereby acupuncture can help to improve IVF outcomes.