Ovarian Cyst and Baby Delivery: Ovarian cysts are fluid-filled sacs that can form on the ovaries. They are common in women of all ages, and they are especially common during pregnancy. Most ovarian cysts are harmless and do not cause any problems. However, some ovarian cysts can grow large enough to cause pain, pressure, or other symptoms. In rare cases, an ovarian cyst can rupture, which can be a serious medical emergency. If you have an ovarian cyst during pregnancy, your doctor will monitor y