Mazal tov on the recent birth of your baby!
While our general recommendation is to wait until 24 hours after the staining has subsided before resuming relations, in situations where there may be continual staining issues, there is more flexibility. It is important to note that abstaining for 24 hours while staining is not a halachic requirement – rather a recommended precaution to help avoid the halachically problematic situation of finding blood during/after intercourse.
Therefore, if staining may be a continual issue and waiting 24 hours after each episode will effectively bar you from being intimate with your husband, we recommend checking shortly before relations to see whether you are staining. Do not perform a bedikah; rather, you can externally wipe yourself with toilet paper (not after urinating) to see whether you are staining. If you are not staining, go ahead with intercourse. If you are still staining, try again the next day.
After relations, you should wait a few minutes before getting up. Make sure that your sheets are colored, and that you and your husband wipe yourselves with colored towels. Do not look to see if there was any staining on you or your husband. If you do use the diaphragm, when you rinse it off, do not look. Close your eyes, or turn off the lights if necessary. There is no obligation to look for any stains at a time you are not expecting your period, and you should take precautions against finding any staining.
Once the staining seems to subside, you should not continue to check for further staining. You may also want to avoid looking at your toilet paper, and take care to wear colored underwear to avoid becoming niddah should the staining resume. You can read our article on stains for further details.
Note that a diaphragm should be refitted after childbirth, or after any weight gain or loss of about ten pounds (five kilograms).
Please feel free to get back to us with any further questions.