Dictionary DifficultySperm ProblemsPolyspermy Polyspermy Reviewed by Ashley Wong, MS, Clinical Embryologist View our Editorial Policy Published: February 10, 2018 What Does Polyspermy Mean? Polyspermy refers to the fertilization of one egg with multiple sperm cells that result in the formation of an embryo with abnormal sets of chromosomes. This typically happens with conventional insemination where the egg and the sperm are placed in the same culture environment for fertilization. Pregnancies that result from polyspermy often result in spontaneous miscarriages during the second or third trimesters of pregnancy and fetuses that survive until childbirth are likely to not survive beyond a few days. Polyspermy can also complicate in vitro fertilization (IVF) by producing non-viable embryos. FertilitySmarts Explains Polyspermy Chromosomes carry the genetic material in the cells. A healthy human cell contains 46 chromosomes arranged as 23 pairs and are known as diploid cells. When gametes (eggs and sperm) are formed, each cell receives one set, which is 23 of these chromosomes. During fertilization, these two sets from the sperm and egg unite to form an embryo with 46 chromosomes. In polyspermy, an abnormal number of sperm fertilize a single egg, resulting in an embryo with an abnormal set of chromosomes. This condition is called triploid syndrome, also called triploidy and is known as a diandric fertilization. In Vitro Fertilization Polyspermy can also occur during in vitro fertilization. But with advances in IVF techniques and preimplantation genetic screening (PGS), the risk of polyspermy leading to a triploid pregnancy is minimized. Share This Term> Related Terms Sperm Concentration Acrosome Reaction Zona Pellucida 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 Egg Sperm Difficulty Sperm Problems 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?