Polyps are normally quite small. Most are no larger than a small cherry, but some can go on to be the size of an apple. If you are pregnant and have polyps, the increase in the hormone pregnancy can lead the polyps to increase in size faster. Most polyps are symptomless, meaning that you have had no reason to suspect you had them before you became pregnant. When your doctor catches them while you are still trying to conceive, they may well suggest removal. Having uterine polyps while pregnant does increase your risk of having a miscarriage, but surgical removal or hormone replacement therapy to shrink the polyps down is not generally considered safe for women who are expecting a baby.
If you have been diagnosed with uterine polyps, you might have more frequent ultrasounds to monitor whether your polyps are growing. In some cases, removal may be recommended even during pregnancy, especially when they are so large they are interfering with the growing space you baby has. Discuss this with your healthcare provider in detail what are the pros and cons? and even get a second opinion if you are concerned. Women who are undergoing IVF are almost always recommended to remove any uterine polyps before embryos are transferred to the uterus. If you have a history of miscarriage, ask your doctor to check if you may have uterine polyps.