Bladder pressure in primigravidas increases from 8 cm H20 early in pregnancy to 20 cm H20 at term (Iosif, 1980). To compensate for reduced bladder capacity, absolute and functional urethral lengths increased by 6.7 and 4.8 mm, respectively. Concurrently, maximal intraurethral pressure rises from 70 to 93 cm H20, and thus continence is maintained. Still, at least half of women experience some degree of urinary incontinence by the third trimester (Abdullah, 20 16a). Indeed, this is always considered in the diferential diagnosis of ruptured membranes. Near term-particularly in nulliparas, in whom the presenting part often engages before labor-the entire base of the bladder is pushed ventral and cephalad. his converts the normally convex surface into a concavity. As a result, diiculties in diagnostic and therapeutic procedures are greatly accentuated. Moreover, pressure from the presenting part impairs blood and lymph drainage from the bladder base, often rendering the area edematous, easily traumatized, and possibly more susceptible to infection.
As pregnancy progresses, the stomach and intestines are displaced cephalad by the enlarging uterus. Consequently, the physical findings in certain diseases are altered. he appendix, for instance, is usually displaced upward and somewhat laterally. At times, it may reach the right lank.
Pyrosis (heartburn) is common during pregnancy and is most likely caused by reflux of acidic secretions into the lower esophagus. Although the altered stomach position probably contributes to its frequency, lower esophageal sphincter tone also is decreased. In addition, intraesophageal pressures are lower and intragastric pressures higher in pregnant women. Concurrently, esophageal peristalsis has lower wave speed and lower amplitude (Ulmsten, 1978).
Gastric empying time is unchanged during each trimester and compared with nonpregnant women (Macfie, 1991; Wong, 2002, 2007). During labor, however, and especially after administration of analgesics, gastric emptying time may be appreciably prolonged. As a result, one danger of general anesthesia for delivery is regurgitation and aspiration of either food-laden or highly acidic gastric contents.
Hemorrhoids are common during pregnancy (Shin, 2015). hey are caused in large measure by constipation and elevated pressure in rectal veins below the level of the enlarged uterus.
Liver size does not enlarge during human pregnancy. Hepatic arterial and portal venous blood flow, however, increase substantively (Clapp, 2000).
Some laboratory test results of hepatic function are altered in normal pregnancy (Appendix, p. 1257). Total alkaline phosphatase activity almost doubles, but much of the rise is attributable to heat-stable placental alkaline phosphatase isozymes. Serum aspartate transaminase (AST) , alanine transaminase (AL T), 1-glutamyl transpeptidase (GGT), and bilirubin levels are slightly lower compared with nonpregnant values (Cattozzo, 2013; Ruiz-Extremera, 2005).
The serum albumin concentration declines during pregnancy. By late pregnancy, albumin levels may be near 3.0 g/dL compared with approximately 4.3 g/dL in nonpregnant women (Mendenhall, 1970). Total body albumin levels rise, however, because of pregnancy-associated increased plasma volume. Serum globulin levels are also slightly higher.