Only one ovary can be seen on one side of the uterus when an ultrasound is done, either due to a congenital absence of one ovary or due to interference from excess intestinal gas. Normally, there is one ovary on each side of the uterus, and you should be able to see both ovaries during the ultrasound. If only one ovary is visible on ultrasound, consider the following factors: 1. Congenital absence of one ovary. A few female patients have congenital abnormalities of uterine and ovarian development, such as having a unicornuate uterus, and only one ovary will be seen on ultrasound. 2. Excessive interference of gas in the intestines. If there is too much gas in the intestines during the abdominal ultrasound, one ovary may not be seen due to gas interference. If you suspect that this is the case, you can use laxatives to promote gas and bowel movement, and then do ultrasound again. There may be other reasons why only one ovary is visible during the ultrasound, and it is recommended that a definitive diagnosis be made under the guidance of a medical professional.