位置、形态与功能

子宫( uterus,拉丁语：发源地)是一个肌肉状器官，位于两侧卵巢之间、略靠下，约在下腹部的中央。这个大约3英寸（7cm）长的器官，其形状像似一个倒置的小鸭梨。在其顶端的两侧，有输卵管进入。其宽阔的上端，称为子宫底，倚靠在圆隆的膀胱上方，而且与略微缩小的窄小下端相分隔。子宫的这个窄小下端部分称为子宫颈，其末端向下延伸入阴道。子宫颈有一个开口，精子通过这个开口能够从阴道进入子宫。但是，除排卵的特定时间以外，子宫颈的开口由难以渗透的粘液所栓塞。

子宫壁
厚厚的子宫壁由三层结构所组成：

子宫内膜由特殊的组织所组成，当子宫预备为受精卵植入作好准备时，它按月会增厚。如果没有植入发生，子宫内膜会在月经期溃破和通过子宫颈和阴道排放出去（既形成月经-译者注）。

妊娠期的子宫
假若怀孕了，子宫会随着胎儿的生长而扩张。子宫肌层的这些非凡的肌肉结构不仅适应于如此的膨胀，而且在胎儿最终分娩时收缩，提供必需的压力。在性高潮期，子宫肌也会收缩。

Location, form and function
The uterus (lat.: womb) is a muscular organ which is situated between and slightly below the ovaries, approximately in the center of the lower abdomen. The shape of the uterus, which is about 3 inches (ca. 7 cm) long, resembles that of a small pear turned upside down. The Fallopian tubes enter the uterus on either side near the top. The wide upper part, known as the body of the uterus, is usually tilted forward over the dome of the urinary bladder, and it is separated from the narrow lower part by a slight constriction. This lower part is called the cervix or neck of the uterus, and it ends in the deep portion of the vagina. The cervix contains a small opening through which sperm cells can travel from the vagina into the uterus. However, except for a certain period during ovulation, the cervical opening is plugged by an impenetrable mucus.

The three layers of the uterine wall
The thick walls of the uterus are made up of three layers:

This endometrium consists of special tissue which thickens every month as the uterus prepares for the possible implantation of a fertilized egg. If no implantation occurs, the endometrium deteriorates and is discharged through the cervix and the vagina during menstruation.

The uterus during pregnancy
In case of a pregnancy, the uterus expands with the growing fetus. The extraordinary muscular structure of the myometrium not only allows for such vast expansion, but also provides the necessary pressure during labor when the fetus is finally expelled. The uterine muscles also contract during orgasm.