Involution of uterus occurs at the rate of: September 2009
**Core Concept**
Involution of the uterus is the process of the uterus returning to its pre-pregnancy size and shape after childbirth. This process involves the contraction of the uterine muscle and the reabsorption of the decidua, the layer of tissue that was formed during pregnancy.
**Why the Correct Answer is Right**
The involution of the uterus is a physiological process that occurs in the postpartum period. The uterus contracts and shrinks due to the action of oxytocin and prostaglandins, which stimulate the uterine muscle to contract and reduce its size. The decidua is reabsorbed, and the endometrium returns to its pre-pregnancy state. This process usually takes around 6-8 weeks to complete.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not provide a specific rate or time frame for the involution of the uterus.
* **Option B:** This option is incorrect because it is too slow for the rate of involution of the uterus, which typically occurs rapidly in the postpartum period.
* **Option C:** This option is incorrect because it is too fast for the rate of involution of the uterus, which typically takes several weeks to complete.
**Clinical Pearl / High-Yield Fact**
The rate of involution of the uterus is an important clinical indicator of uterine health and can be used to assess the effectiveness of postpartum care. A uterus that does not involute properly may be at risk for complications such as hemorrhage or infection.
**Correct Answer:** C. 5 cm per week