Take a Poll

If HG continued past mid-pregnancy, did you experience complications during delivery related to your poor health such as a strained ligaments/joints, pelvic floor damage, prolonged or weak pushing, fainting, low blood pressure, low pain tolerance, forceps/assisted delivery, broken bones, nerve damage, low amniotic fluid, fetal problems due to difficult delivery, etc.?


View Results »

Other Theories & Links

Links & abstracts to various other physiological and immunological theories.

New Approaches:

Nausea and vomiting of pregnancy: an obstetric syndrome.
Goodwin TM.
University of Southern California, USA.
Am J Obstet Gynecol 2002 May;185(5 Suppl Understanding):S184-9.

Although the cause of nausea and vomiting of pregnancy is not known, there is strong evidence linking human chorionic gonadoptropin or estrogens. Evidence is presented to show that the incidence and severity of nausea and vomiting of pregnancy is linked to temporal and pathologic alterations in these hormones during pregnancy. The way in which the pregnant woman responds to the primary stimulus to nausea and vomiting of pregnancy appears to depend on her susceptibility mediated by vestibular, gastrointestinal, olfactory, and behavioral pathways. Conceiving of nausea and vomiting of pregnancy as a syndrome suggests new pathways of investigation and possible therapies.

Other Physiological:

The etiology of nausea and vomiting of pregnancy
Peter von Dadelszen
Nausea and Vomiting of Pregnancy: State of the Art 2000 Conference

Morning sickness and salt intake, food cravings, and food aversions.
Crystal SR, Bowen DJ, Bernstein IL.
Department of Psychology, University of Washington, Seattle 98105, USA.
Physiological Behavioral 1999 Aug;67(2):181-7 (ISSN: 0031-9384)

Evidence for an association between early pregnancy sickness and offspring salt (NaCl) preference has been obtained from studying offspring as young adults and as infants. To determine whether the association between early pregnancy sickness and salt preference of offspring is secondary to familiar similarity in salt preference, the present study examined the self-reported salt intake and dietary cravings and aversions of pregnant women. Women who reported little or no vomiting (n = 108) were compared to women who reported moderate to severe vomiting (n = 21) during pregnancy. The women's self-reported salt use and reported cravings and aversions for common food were measured via survey for time periods prior to and during their current pregnancy. Women did not differ in reported salt use prior to pregnancy as a function of their pregnancy symptoms. Women reported more aversions during, than prior to, pregnancy (p < 0.05). Women with more severe vomiting reported a greater number of aversions (p < 0.05) both prior to and during pregnancy. There was a significant association between experiencing cravings and aversions prior to pregnancy and experiencing craving and aversions during pregnancy (p < 0.05). These findings do not provide evidence for an association between dietary levels of sodium and the likelihood of experiencing severe pregnancy symptoms. Therefore, these data do not support the suggestion that reported elevations in salt preference in offspring of women with moderate to severe vomiting during pregnancy are mediated by familial dietary practices.


Sympathetic Nervous System:

Mechanisms underlying immunologic states during pregnancy: possible association of the sympathetic nervous system.
Minagawa M, Narita J, Tada T, Maruyama S, Shimizu T, Bannai M, Oya H, Hatakeyama K, Abo T.
Department of Immunology, Niigata University School of Medicine, Niigata, 951-8510, Japan.
Cellular Immunology 1999 Aug 25;196(1):1-13

Cell-Free Fetal DNA:

Cell-free fetal DNA is increased in plasma of women with hyperemesis gravidarum.
Sekizawa A, Sugito Y, Iwasaki M, Watanabe A, Jimbo M, Hoshi S, Saito H, Okai T.
Department of Immunology, Niigata University School of Medicine, Niigata, 951-8510, Japan.
Clinical Chemistry. 2001 Dec;47(12):2164-5

Helicobacter Pylori Infection:

Detection of Helicobacter pylori seropositivity in hyperemesis gravidarum and correlation with symptoms.
Erdem A, Arslan M, Erdem M, Yildirim G, Himmetoglu O.
American Journal of Perinatology. 2002 Feb;19(2):87-92.

Helicobacter pylori and severe morning sickness.
Reymunde A, Santiago N, Perez L.
American Journal of Gastroenterology. 2001 Jul;96(7):2279-80

Vestibular Disorders:

Maternal susceptibility to nausea and vomiting of pregnancy: is the vestibular system involved?
Black FO.
American Journal of Obstetrics and Gynecology. 2002 May;185(5 Suppl Understanding):S204-9

Evolutionary Protective Mechanisms:

Nausea and vomiting of pregnancy in an evolutionary perspective.
Sherman PW, Flaxman SM.
American Journal of Obstetrics and Gynecology. 2002 May;185(5 Suppl Understanding):S190-7


Hyperolfaction and hyperemesis gravidarum: what is the relationship?
Erick M.
Nutrition Reviews. 1995 Oct;53(10):289-95

The exact etiology of hyperemesis gravidarum (pernicious vomiting of pregnancy) is unknown, but hyperolfaction may be one contributing factor. The net result of hyperolfaction in pregnancy may be a mechanism cuing the pregnant woman to seek a cleaner, quieter, more temperate environment.

Linking olfaction with nausea and vomiting of pregnancy, recurrent abortion, hyperemesis gravidarum, and migraine headache.
Heinrichs L.
American Journal of Obstetrics and Gynecology. 2002 May;185(5 Suppl Understanding):S215-9

In a small sample of women with congenital anosmia, nausea and vomiting of pregnancy occurred in only 1 pregnancy, suggesting that olfaction is a highly selected trigger for nausea and vomiting of pregnancy.

Long-chain L-3-hydroxyacyl-coenzyme a dehydrogenase deficiency:

Long-chain L-3-hydroxyacyl-coenzyme a dehydrogenase deficiency: a molecular and biochemical review.
Rakheja D, Bennett MJ, Rogers BB.
Laboratory investigation: a journal of technical methods and pathology. 2002 Jul;82(7):815-24

Updated on: Apr. 18, 2013

Copyright © 2000-2015 H.E.R. Foundation • 9600 SE 257th Drive • Damascus, OR 97089 USA