Gastroesophageal Reflux and Related Discomfort During Gestation

Physiological Changes in the Digestive System

Gestation prompts several significant alterations in a woman's body, impacting the gastrointestinal system. Hormonal fluctuations, particularly increased progesterone levels, contribute to smooth muscle relaxation. This relaxation affects the lower esophageal sphincter (LES), reducing its tone and allowing stomach contents to reflux into the esophagus. Furthermore, elevated levels of estrogen may also influence gastric emptying.

Mechanical Factors

As the uterus expands to accommodate the growing fetus, it exerts increasing pressure on the stomach. This mechanical pressure can displace the stomach and compress it, reducing its capacity and increasing the likelihood of stomach contents being forced upwards into the esophagus. Later in gestation, this effect becomes more pronounced.

Hormonal Influences

Progesterone's impact extends beyond LES relaxation. It also slows down gastric motility, meaning that food remains in the stomach for a longer period. This prolonged gastric emptying contributes to increased pressure and distention, making reflux more probable.

Dietary and Lifestyle Considerations

Certain dietary habits and lifestyle choices can exacerbate these symptoms. Large meals, high-fat foods, caffeinated beverages, and carbonated drinks can all contribute to increased gastric pressure and reflux. Lying down shortly after eating can also facilitate the upward movement of stomach acid.

Pre-existing Conditions

Individuals with a history of gastroesophageal reflux disease (GERD) or hiatal hernia may experience a worsening of their symptoms during this time. The physiological and mechanical changes of gestation can compound existing vulnerabilities in the gastroesophageal system.

Delayed Gastric Emptying

Studies have shown that the rate at which the stomach empties its contents slows down as pregnancy progresses. This delayed emptying increases gastric distention and the risk of acid reflux. Several factors contribute to this including hormonal changes and possible compression of the stomach by the growing uterus.