# Uterus
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The **uterus** is a part of the [[female reproductive system]] where the baby grows during [[pregnancy]]. It sits above the [[vagina]] and opens into it through a structure called the [[cervix]]. On either side two **uterine tubes** stretch out to partially envelop the [[ovaries]], where they "catch" the ovulated oocyte with finger-like projections called fimbriae. Then the uterine tubes transport the oocyte to the uterus with a combination of cilia on the apical curves that wish the egg along as well as some [[peristalsis]] contractions.
![[uterus and ovaries.png]]
>[!abstract] Eponym elimination
>**Uterine tubes** are commonly referred to as Fallopian tubes, but that term is growing [[eponym elimination|out of favor]]
## Anatomy
There are four main parts of the uterus, the **fundus** as the top, the main part or the **body**, the **isthmus** and the **cervix**. The tissue of the uterine wall in the body is made up of three layers, from outermost to innermost: the perimetrium, myometrium and endometrium. The endometrium is made up of two layers, the **basal layer** and the **functional layer** which is what is shed a menses if a [[menstrual cycle]] passes with no fertilization/implantation.
The cervix has two openings, the **internal os** inside the uterus and the **external os** inside the vagina. The external os has special mucus secreting cells that form a mucus plug, or a physical barrier into the uterus.
## The Uterus During Pregnancy
The uterus grows and changes throughout pregnancy.
At the end of pregnancy the uterus undergoes [[uterine involution]] where it returns to it's non-pregnant state.
The uterus is supported by two rope like bands of connective tissues called the **round ligaments**. They are each about 4 inches in length. When the uterus expands during [[pregnancy]] this can cause tension and pain on the anterior round ligament.
![[round ligament.png]]
## Problems with the Uterus
- [[fibroids]]
- [[endometriosis]]
- [[uterine cancer]]
- [[cervical cancer]]
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