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Maternal adaptations to pregnancy: Gastrointestinal tract

Angela Bianco, MD
Section Editor
Charles J Lockwood, MD, MHCM
Deputy Editor
Kristen Eckler, MD, FACOG


Pregnancy has little, if any, effect on gastrointestinal secretion or absorption, but it has a major effect on gastrointestinal motility. Pregnancy-related changes in motility are present throughout the gastrointestinal tract and are related to increased levels of female sex hormones. In addition, the enlarging uterus displaces bowel, which can affect the presentation of disorders such as appendicitis. Knowledge of the gastrointestinal adaptation to pregnancy is necessary for accurate interpretation of laboratory tests, as well as imaging studies in the gravid patient.

Maternal gastrointestinal tract changes during pregnancy and common gastrointestinal disorders related to pregnancy will be reviewed here.


The mucous membrane lining the oropharynx is responsive to the hormonal changes related to pregnancy. The gingiva is primarily affected, while the teeth, tongue, and salivary glands are spared, although excessive salivation during pregnancy has been described [1]. The effect of pregnancy on the initiation or progression of caries is not clear; pregnancy-related changes in the oral environment (salivary pH, oral flora) or in maternal diet and oral hygiene may increase the risk of caries [2]. (See "Maternal adaptations to pregnancy: Skin, hair, nails, and mucous membranes", section on 'Mucous membranes'.)

Taste — Most studies suggest that taste perception changes during pregnancy [3-6]. The etiology is unknown and the direction of taste change varies among studies.


Gingivitis — Enlargement and blunting of the interdental papillae of the gingiva may result in gingival bleeding, ulceration, and pain. Gingival inflammatory symptoms are frequently aggravated during pregnancy; prevalence rates of 40 to 100 percent have been reported [7]. The cause of pregnancy-induced gingivitis (picture 1) is likely multifactorial and includes pregnancy hormone-related vascular and inflammatory changes [8-12].

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Literature review current through: Sep 2017. | This topic last updated: Aug 03, 2017.
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