Yes, it is possible. As long as partial oophorectomy done correctly, your chance of pregnancy is still possible. It also depends on the reason for oophorectomy. I have a patient who had severe endometriosis, and her gynecologist performed bilateral partial oophorectomy, and she developed premature ovarian failure. If patient developed pelvic adhesion, the chance of natural conception will reduced.
Yes. It may be harder. There is a blood test called anti mullerian hormones that can measure the number of eggs you still have left. It may be harder to become pregnant. Surgery may have even caused scar tissue which affected the fallopian tubes. But absolutely you can still become pregnant.
Yes, May be harder. You almost certainly have diminished ovarian reserve or reduced egg supply, and the more normal ovarian tissue was removed at the surgery the less eggs you have left. The surgery may have created scar tissue around your ovaries as well. Your age is a factor, but even young women may have problems. Get ovarian reserve evaluation and treatment plan from reproductive endocrinologist. You may need ivf.
Yes. While such surgery may have diminished your supply of eggs, if no other pelvic damage has occurred in association with the reason you needed to have the parts of the ovary removed, pregnancy is certainly possible. An older technique for improving fertility actually consisted of removing portions of each ovary.