Braxton Hicks contractions, also known as practice contractions or false labor, are sporadic uterine contractions that may start around six weeks into a pregnancy. However, they are usually felt in the second or third trimester of pregnancy. Associated conditions
Braxton Hicks contractions are often confused for labor. Braxton Hicks contractions allow the pregnant womans body to prepare for labor. However, the presence of Braxton Hicks contractions does not mean a woman is in labor or even that labor is about to commence. Another common cause of pain in pregnancy is round ligament pain. Table 1. Braxton Hicks contractions vs. True Labor

Pathophysiology
Although the exact causes of Braxton Hicks contractions are not fully understood, there are known triggers that cause Braxton Hicks contractions, such as when a pregnant woman:
is dehydrated
has a full bladder
has just had sexual intercourse
has been exercising (running, lifting heavy objects)
is under excessive stress
has had her stomach touchedThere are two thoughts for why these intermittent uterine muscle contractions may be occurring. The first is that these early “practice contractions” could be helping to prepare the body for true labor by strengthening the uterine muscle. The second is that these contractions may occur when the fetus is in a state of physiological stress, in order to help provide more oxygenated blood to the fetal circulation. Signs and symptoms
The determination of Braxton Hicks contractions is dependent on the history and physical assessment of the pregnant womans abdomen, as there are no specific imaging tests for diagnosis.
In 1872, he investigated the later stages of pregnancy and noted that many pregnant women felt contractions without being near birth. He examined the prevalence of uterine contractions throughout pregnancy and determined that contractions that do not lead to labor are a normal part of pregnancy. == References ==