Wallace WHB, Kelsey TW. 2010. Human ovarian reserve from conception to the menopause. PloS One 5(1): e8772. journals.plos.org Opens a new window [Accessed May 2020] The uterus is a muscular bag with a soft lining. The uterus is where a baby develops until birth. The cervix is a ring of muscle at the lower end of the uterus. It keeps the baby in place during pregnancy. Knudtson J, McLaughlin JE. 2019. Female reproductive endocrinology. MSD Manual, Professional Version. www.msdmanuals.com Opens a new window [Accessed May 2020]

Hirsch IH. 2019. Overview of male sexual function. www.msdmanuals.com Opens a new window [Accessed May 2020] Want to work out when you ovulate? Try out our ovulation calculator. Pinpointing the day of ovulation can help you work out your fertile window. An opening between the uterus and vagina called the cervix, allow sperm in and menstrual blood out. The vagina, or birth canal, connects the cervix to the outside of the body.

The function of the male reproductive system is to produce sperm cells - male gametes - and release them inside a female. Humans reproduce through sexual reproduction. This produces offspring that are genetically unique because half of their genetic material - DNA - comes from each parent. Its main function is to allow the exchange of materials such as oxygen and nutrients between the fetus and mother whilst removing waste substances such as carbon dioxide and urea. This relies on a process called diffusion as there is no mixing of maternal and fetal blood in the placenta. BabyCentre's editorial team is committed to providing the most helpful and trustworthy pregnancy and parenting information in the world. When creating and updating content, we rely on credible sources: respected health organisations, professional groups of doctors and other experts, and published studies in peer-reviewed journals. We believe you should always know the source of the information you're seeing. Learn more about our editorial and medical review policies.

In male reproductive organs, the scrotum holds the testes, which produce sperm and sex hormones, including testosterone. During ejaculation, the sperm pass through the sperm duct and combine with seminal fluid produced by the glands to create semen, which exits the body through the penis. Ovulation is usually about 10 to 16 days before your next period starts. The exact time of ovulation depends on the length of your cycle. Several different hormones work together to control the length of your cycle, when your eggs ripen and the timing of ovulation. You can read more about these hormones in our article on the menstrual cycle. To make female sex hormones, which affect the way bodies develop and also regulates the menstrual cycle. Part of the tip of the head of the sperm releases enzymes to digest the egg membrane to allow fertilisation to take place.Each cycle an egg travels from an ovary through the oviduct to the uterus or womb, where it settles. In addition to all the fun, your bodies are building up tension that you hope will end in orgasm. Having an orgasm also has an important biological function. In men, an orgasm propels sperm-rich semen into the vagina and up towards the cervix at roughly 10 miles per hour. The force of ejaculation gives the sperm a good head start on their way to the egg.