In Africa and Asia obstructed labor affects between two and five percent of deliveries. In 2015 about 6.5 million cases of obstructed labour or uterine rupture occurred. This resulted in 23,000 maternal deaths down from 29,000 deaths in 1990 (about 8% of all deaths related to pregnancy). It is also one of the leading causes of stillbirth. Most deaths due to this condition occur in the developing world. Cause
The main causes of obstructed labour include: a large or abnormally positioned baby, a small pelvis, and problems with the birth canal. Both the size and the position of the fetus can lead to obstructed labor. Abnormal positioning includes shoulder dystocia where the anterior shoulder does not pass easily below the pubic bone. A small pelvis of the mother can be a result of many factors. Risk factors for a small pelvis include malnutrition and a lack of exposure to sunlight causing vitamin D deficiency. A deficiency in calcium can also result in a small pelvis as the structures of the pelvic bones will be weak due to the lack of calcium. A relationship between maternal height and pelvis size is present and can be used to predict the possibility of obstructed labor. This relationship is a result of the mothers nutritional health throughout her life leading up to childbirth. Younger mothers are also at more risk for obstructed labor due to growth of the pelvis not being completed.
Oroantral fistula (OAF) is an epithelialised oroantral communication (OAC). OAC refers to an abnormal connection between the oral cavity and antrum (or maxillary sinus). The creation of an OAC is most commonly due to the extraction of a maxillary (upper) tooth (typically a maxillary first molar) closely related to the antral floor (floor of the maxillary sinus). A small OAC (up to 5mm wide) may heal spontaneously but a larger OAC would require surgical closure to prevent the development of persistent OAF and chronic sinusitis. Classification
Signs and symptoms of an OAC/OAF can include the following
When looking in the mouth, a communication in the upper jaw (i.e. a hole) can be seen connecting the mouth to the maxillary sinus. Sometimes this can be the only sign, as pain (+/- other symptoms) is not always present. Symptoms
· Same side nose blockage (unilateral nasal obstruction). When an OAC or OAF is present, the passage to the maxillary sinus can results in infection and inflammation in the maxillary sinus. This subsequently results in mucus build up presenting as a unilateral nasal blockage
· Sinusitis can progress – this can present as a pain in the midface. Pain can be referred to the upper teeth and be mistaken for toothache· Fluid can flow from the mouth through the communication and into the maxillary sinus.