Abdominal pain during pregnancy
Mitchell S.Cappell,MD,PhD,FACG a,b,*,
David Friedel,MD c
a Division of Gastroenterology,Department of Medicine,Woodhull Medical Center,
760Broadway Avenue,Brooklyn,NY 11206,USA
b State University of New York Downstate Medical School,450Clarkson Avenue,
Brooklyn,NY 11203,USA
c Division of Gastroenterology,Department of Medicine,
Temple University School of Medicine,3401North Broad Street,Philadelphia,
PA 19149,USA
Abdominal pain is a common complaint of female inpatients and outpatients of all ages [1],including women during their childbearing years,and thus often occurs during pregnancy.Abdominal pain during pregnancy presents unique clinical challenges.First,the differential diagnosis during pregnancy is extensive,in that the abdominal pain may be caused by obstetric or gynecologic disorders related to pregnancy,as well as by intraabdominal diseases incidental to pregnancy.
Second,the clinical presentation and natural history of many abdominal disorders are altered during pregnancy.Third,the diagnostic evaluation is altered and constrained by pregnancy.For example,radiologic tests and invasive examinations raise issues of fetal safety during pregnancy.Fourth,the interests of both the mother and the fetus must be considered in therapy during ually,these interests do not conflict,because what is good for the mother is generally good for the fetus.Sometimes,however,maternal therapy must be modified to substitute alternative but safer therapy because of concerns about drug teratogenicity (eg,substituting a histamine 2receptor antagonist for misoprostol,an abortifacient that is contraindicated during pregnancy)[2,3].Rarely,the maternal and fetal interests are diametri-cally opposed,as in the use of chemotherapy for maternal cancer,a therapy that is potentially life-saving to the mother but life-threatening to the fetus [4].These conflicts raise significant medical,legal,and ethical issues.
Gastroenterologists,as well as obstetricians,gynecologists,internists,and surgeons,should be familiar with the medical and surgical conditions Gastroenterol Clin N Am
32(2003)
1–58
*Corresponding author.Department
of Medicine,Woodhull Medical Center,760
Broadway Avenue,Brooklyn,NY 11206.0889-8553/03/$–see front matter Ó2003,Elsevier Science (USA).All rights reserved.PII:S 0889-8553(02)00064-X
2M.S.Cappell,D.Friedel/Gastroenterol Clin N Am32(2003)1–58
that can present in pregnancy and how these conditions affect and are affected by pregnancy.This article reviews obstetric,gynecologic,medical, and surgical causes of abdominal pain during pregnancy,with a focus on aspects of abdominal diseases unique to pregnancy.
Abdominal pain during pregnancy:general considerations Neurophysiology of abdominal pain
Nociception involves affective or autonomic reflexes from abdominal viscera to the cerebral cortex involving three levels of neurons.Thefirst-order neurons are either C or A-deltafibers.Cfibers are narrow,slowly conducting,and unmyelinated and produce a dull and nonlocalized sensation of pain.A-deltafibers are wider,partly myelinated,and faster conducting and produce a sharp and localized sensation of pain.Thefirst-level afferent neurons travel from abdominal structures to synapse in the dorsal horn of the spinal cord.The second-order neurons cross the mid-line to the contralateral side of the spinal cord to ascend through the spinothalamic and spinoreticular tracts to the thalamic and reticular areas of the pons and medulla[5].Third-order neurons travel to the limbic system and sensory cortex where pain is perceived[6–8].
Abdominal pain can be visceral,arising from gastrointestinal organs; parietal,arising from peritoneal irritation;somatic,arising from the abdominal wall;neurologic,arising from diseases affecting abdominal nerves;extraintestinal,from referred pain;or cerebral,from neuropyschi-atric disorders or factitious disease.Visceral pain tends to be dull,poorly localized,and perceived in the midabdomen because afferent nervefibers from abdominal viscera typically are Cfibers and receive multisegmental and bilateral afferent innervation from the spinal cord.Visceral pain may be accompanied by autonomic concomitants of nausea,diaphoresis,and pallor.Abdominal viscera are most sensitive to mural stretch.Parietal pain tends to be more acute,intense,and focal because it is conveyed by a mixture of A-delta and Cfibers and tends to have more discrete innerva-tion from the spinal cord[9].Parietal pain is exacerbated by coughing, movement,and deep inspiration.Somatic tissue in skin,subcutaneous tissue,and muscle is innervated predominantly by A-delta nervefibers so that somatic pain is focal and sharp.
Referred pain is felt remotely from the affected area because of the convergence of visceral and somatic afferent neurons to the same level of the spinal cord and the use of the same second-order neurons.For example, pain from gastrointestinal disorders,such as acute cholecystitis,or pain from obstetric disorders,such as ectopic pregnancy,may be referred to the shoulder or back[10].Conversely,pain from an extraabdominal condition, such as a migraine headache,may be referred to the abdomen.
