Any kind of stress, such as moving or changing jobs, can interfere with ovulation.   Often this will cause a late period followed by irregular bleeding.  Usually the bleeding will resolve by itself without any treatment. 

Long standing ovulation can cause extremely heavy menstrual bleeding.  If a woman is trying to conceive, then it is usually possible to induce ovulation with medication.  More often, conception is not desired.  Cycling with progesterone will usually control this type of bleeding.  This usually involves taking natural or synthetic progesterone for 12 to 14 days a month.  The progesterone causes the endometrium (lining of the uterus) to become spongy, and when the progesterone is stopped the lining is shed.  Often the first few periods are quite heavy as the thickened lining is shed, but usually becomes much lighter after several cycles.

Another alternative is taking oral contraceptive pills (birth control pills).   These contain both estrogen and progesterone, and also offer a reliable method of contraception.

Bleeding from fibroids and unexplained bleeding:

Even if a woman is ovulating normally, bleeding will often be lighter if she takes birth control pills.  Cramping is also usually less when she is on the pill.   Some women who otherwise would require surgical treatment can avoid surgery by taking oral contraceptives.  With new low-dose pills, the risks are low, and most physicians agree that women can take them until menopause.  One major exception is women who smoke, as the risk of birth control pills in women over the age of 35 in smokers is unacceptable. 

Anti-prostaglandins, such as ibuprofen and naproxen sodium can decrease menstrual bleeding as well.  Even more effective are Meclomen™ and Ponstel™.   These medicines can cause a significant decrease in menstrual flow as well as a decrease in cramping.  They may, however, increase the length of the period.   This is less of a problem if a woman has short but heavy periods than if she bleeds for a number of days.

Progesterone coated IUD:

The progesterone coated Mirena IUD may decrease menstrual bleeding.  It also can be effective with adenomyosis. 

 I have seen a many women for surgical consultations in whom we were able to avoid surgery by using medications.