Dictionary HealthFemale Reproductive SystemOocyte Oocyte Reviewed by Ashley Wong, MS, Clinical Embryologist View our Editorial Policy Published: August 6, 2016 What Does Oocyte Mean? An oocyte is an immature egg that needs to mature before fertilization can occur. It is the female germ cell involved in reproduction that develops from within a follicle inside in the ovaries. After becoming a secondary follicle and then Graafian follicle, an egg or ovum is released through the process of ovulation. Normally one follicle will become a mature egg with each menstrual cycle. An oocyte is also known as an immature egg cell. FertilitySmarts Explains Oocyte At birth, a woman has all the oocytes that she will have for life. This number drops with age and after each normal menstrual cycle. An oocyte will mature during the first week of the menstrual cycle. Up to two days before ovulation, the oocyte will be nourished by the surrounding cells. As this process happens, the surrounding cells start to proliferate and produce a high progesterone concentration. Then the follicle will release a fluid along with the oocyte to allow for a smooth flow of the mature egg to the fallopian tubes, where fertilization may take place. An oocyte matures into an ovum. Follicle growth can be followed by conducting an ultrasound. Synonyms ovocyte Ocyte öcyte Share This Term> Related Terms Diminished Ovarian Reserve Related Reading 14 Onesies that Celebrate IVF Babies IVF Pregnancy Announcements Fertility Podcasts Relatable Words After a Miscarriage Let’s Stop Arguing About Whether or Not Stress Causes Infertility Books About Infertility Tags Ovulation Egg Menstrual Cycle Health Female Reproductive System Ovaries Embryo Development Trending Articles Pregnancy IVF Pregnancy Announcements Egg Retrieval From Eggs to Blastocysts: Understanding IVF Attrition Cervical Mucus Identifying Stages of Cervical Mucus Artificial Insemination (AI) Implantation Calendar: What is Happening During the Two Week Wait?