What is the difference between bloating before menstruation and bloating during pregnancy?

Generally, the differences between premenstrual bloating and pregnancy-related bloating include different causes, body temperature variations, and differing symptoms, as analyzed in detail below:

1. Different Causes

Premenstrual bloating mainly occurs due to a drop in estrogen levels, which can hinder the shedding of the uterine lining and lead to chronic pelvic congestion, potentially causing bloating. In contrast, bloating during pregnancy is often caused by the growing fetus. As the fetus develops, the uterine cavity gradually expands and may compress surrounding organs, resulting in bloating.

2. Different Body Temperatures

Prior to menstruation, hormonal changes cause a slight decrease in body temperature, typically by 0.3°C to 0.5°C, which returns to normal by the second day of menstruation. In pregnant women, higher levels of progesterone increase metabolic rate, leading to an elevated basal body temperature—about 0.3°C to 0.5°C above normal—that generally remains consistently high without dropping.

3. Different Symptoms

In addition to bloating, premenstrual symptoms may include insomnia, abdominal pain, and increased vaginal discharge. Pregnancy symptoms, however, may also involve weight gain, constipation, and breast enlargement.

Additionally, the duration of symptoms differs. If someone has recently had unprotected sexual intercourse and experiences the above symptoms, pregnancy should be suspected. It is recommended to visit a hospital for blood tests to confirm diagnosis.