The fundus of the uterus is the uppermost portion of the organ. It’s generally defined as the area above the level of the uterine tubes, the part of the uterus that is closest to the stomach. The fundus plays an important role in pregnancy and during childbirth.
The fundus produces hormones that are essential for pregnancy, such as progesterone and estrogen. During pregnancy, the fundus helps to support the growing fetus. It also helps keep the blood vessels in the placenta healthy and regulates blood flow to the placenta. It serves as a storage area for blood and nutrients. It also stores urine until it’s time to be expelled from the body (this is why you might feel like you have to urinate more frequently in early pregnancy). During labor and delivery, it acts as a shock absorber for the baby. After childbirth, the fundus helps to expel the placenta from the body. During this time the fundus also shrinks back down to its pre-pregnancy size. This process is called involution.
Complications Associated with Fundus
Complications can arise if the fundus isn’t functioning properly. For example, if the fundus doesn’t contract correctly after childbirth, it can cause bleeding or retained tissue. In some cases, surgical intervention may be necessary to correct the problem. Problems with the fundus, such as an abnormal shape or size, can also be a contributing factor for miscarriage. Moreover, an abnormal fundal height measurement could indicate an issue with your pregnancy, such as twins or triplets (if it measures larger than expected), intrauterine growth restriction (if it measures smaller than expected), or preeclampsia.
Other Related Terms
Some terms that are closely associated with “fundus” include:
- Corpus luteum
- Endometrium
- Myometrium
- Placenta.
This image shows how often the term ‘Fundus’ is used in relation to other, similar birth terms:

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