fertilization nonhuman 62 priority journal 60 article 58 controlled study 54 male 54 female 48 Fertilization 44 Male 44 animal cell 40 Animals 38 Female 36 Spermatozoa 34 spermatozoon capacitation 34 zona pellucida 32 human 30 sperm 28 acrosome reaction 26 spermatozoon motility 24 unclassified drug 24 Sperm 22 epididymis 22 spermatozoon 22 Animalia 20 Humans 20 mouse 20 oocyte 20 Ovum 18 fertilization in vitro 18 protein phosphorylation 18