Generally, colonics are contraindicated for clients with diverticulitis because of the danger that the pressure used during the colonic that is necessary for the water to reach the upper portion of the ascending colon near the cecum could cause one or more of those little pouches to burst.
If that happened, you would have toxic bacterial waste breaching the protective wall of the colon and that would lead to a very serious, potentially fatal situation.
#10846 in the posting above is correct in advising against colonics for you. A daily salt solution enema of one to 3 pints, and allowing a few ounces in at a time with the bag hanging no more than 18-24 inches above the level of your hips would be far preferable, and will not interfere with your attempt to conceive. Stop the inflow as soon as you feel uncomfortable cramping or fullness and eliminate.