Exacerbation of a maternal hiatus hernia in early pregnancy presenting with symptoms of hyperemesis gravidarum: case report and review of the literature

We report on a 30-year old woman presenting with symptoms of hyperemesis gravidarum and subsequent vomiting at the end of the first trimester (12 + 0 weeks of gestation). The patient was initially presented with nausea and vomiting, without any signs or symptoms of intra-abdominal disorders. On the 2nd day, symptoms became worse and she complained right sided upper abdominal pain, therefore abdominal ultrasound was performed, showing no remarkable findings, explaining the disorder. Clinical symptoms increased and the patient complained suddenly severe dyspnoea and intractable cough. Therefore, immediately an X-ray examination of the thorax was performed showing a severe left sided diaphragmatic hiatus hernia with consecutive displaced stomach into the thoracic cavity, making immediate surgical intervention necessary.

Diaphragmatic hernias complicating pregnancy are a rare event, they normally occur in later periods of pregnancy due to the rising intra-abdominal pressure mainly caused by the enlargement of the uterus. Also maternal diaphragmatic hernias during pregnancy are usually associated with minor complains. However, they can be life-threatening, due to mediastinal shift and cardio-respiratory failure. The majority of maternal diaphragmatic hernias complicating pregnancies occur in antenatal period, most of them in the third trimester. More than 90% of maternal diaphragmatic hernias complicating pregnancy are localized on the left side of the maternal diaphragma. We present a case of an early onset life-threatening maternal diaphragmatic hernia. Usually, maternal diaphragmatic hernias become clinically obvious in advanced stage of pregnancy, in contrast hyperemesis gravidarum is normally occurring in the first trimester and is usually self-limiting. Guiding symptoms for hyperemesis gravidarum are nausea and vomiting, but these clinical findings can also be unspecific symptoms of a maternal diaphragmatic hernia. Therefore, especially mild variants of maternal diaphragmatic hernias in early pregnancy can be misdiagnosed as hyperemesis gravidarum. Nevertheless, the rising intra-abdominal pressure while vomiting obviously can trigger exacerbation of a pre-existing maternal diaphragmatic hernia. We therefore speculate that there could be an association between physiological changes in early pregnancy, for example in gastric motility, and the exacerbation of the pre-existing maternal hiatus hernia.

Hence a diaphragmatic hernia should always be excluded, if symptoms of nausea and vomiting are intractable, mediastinal shift with dyspnoea occurs, failure of conservative treatment especially after 20th week of gestation and in late onset of assumed hyperemesis gravidarum.