Once inside a woman's body, sperm embark on a journey to fertilize an egg, aided by the female reproductive system.
Here's a breakdown of what happens:
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Vaginal Environment: Immediately after ejaculation, sperm are deposited into the vagina, which is an acidic environment. Semen helps to neutralize this acidity, protecting the sperm.
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Cervical Mucus: The sperm then navigate towards the cervix, the opening to the uterus. Cervical mucus plays a crucial role. Around ovulation, the mucus becomes thinner and more hospitable, allowing sperm to pass through more easily. The cervical mucus acts as a reservoir, protecting sperm and extending their survival.
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Uterine Journey: After navigating the cervix, contractions in the uterine walls propel the sperm upward into the fallopian tubes. This journey can be surprisingly rapid, with some sperm reaching the tubes within minutes.
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Fallopian Tubes and Fertilization: The fallopian tubes are where fertilization typically occurs. Sperm can survive in the fallopian tubes for several days, awaiting the arrival of an egg. If an egg is present, sperm will attempt to penetrate its outer layer. It's important to note that the first sperm to arrive are not necessarily the ones that fertilize the egg.
Key Stages Summarized:
| Stage | Description |
|---|---|
| Vagina | Sperm are deposited in the vagina, where semen neutralizes the acidic environment. |
| Cervix | Sperm navigate through the cervical mucus. |
| Uterus | Uterine contractions propel sperm towards the fallopian tubes. |
| Fallopian Tubes | Fertilization occurs in the fallopian tubes. |
In essence, sperm deposited in the vagina navigate through the cervical mucus, are propelled by uterine contractions into the fallopian tubes, where they may encounter and fertilize an egg.
