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Question about Casts
AlwaysPeachy posted:
I have had 2 uterine casts in the past. Both were associated with use of birth control pills including a regular combination pill and a low-estrogen form of the pill as well. Considering this hasn't afflicted me outside of the use of birth control, I have not taken any form for the last 5 years.

Originally I was placed on birth control to regulate my cycle as I am known to have extremely irregular and extremely heavy cycles. Occasionally I will have a regular cycle but always heavy.

I have noticed most feminine doctors I have met do not know about uterine/decidual casts. However, I have moved a bit since I was diagnosed with the issue in earlier years by a previous doctor whom I do not see since I have moved.

Most doctors want to just put me on a different form of the pill without learning more about my issue. I have limited information on this topic. My current doctor, whom prob won't be when I find another, has suggested trying the mini-pill, a progesterone only form of birth control. From what I have read, this issue is caused by progesterone. My pharmacist however is looking more into the issue and is getting back to me this week. I do not want to risk taking another form of birth control and having another cast. I have not had any reason to worry about pregnancy since it seems I can not get pregnant. One doctor suggested PCOS, which was then later contradicted by another doctor who said there was no possibility of PCOS after testing and multiple exams.

I want to know if this issue with casts, if it has effect on potential for pregnancy and also if there is just a normal hormone imbalance that can be tested for and fixed.
Jane Harrison Hohner, RN, RNP responded:
Dear AlwaysPeachy: VERY rarely a woman will pass a "uterine cast". This is when the lining is passed as a triangular shaped bit of tissue similar to the shape of the inside of the uterus. The predisposing condition for passing a uterine cast is abrupt cessation of high dose progesterone therapy. I have also seen a cast associated with an ectopic/tubal pregnancy.

Here is one of the few citations on this from the National Library of Medicine site:

J Pediatr Adolesc Gynecol. 2007 Jun;20(3):191-4. Links Decidual cast in a girl receiving depot medroxyprogesterone acetate--a case report.Singh V, Talib N, Strickland J. Departments of Pathology, Pediatrics, and Gynecological Surgery, Children's Mercy Hospital, Kansas City, Missouri 64108, USA.

BACKGROUND: The passage of tissue per vaginam in a young girl raises several diagnostic considerations that include aborted pregnancy, benign polyp, rhabdomyosarcoma, and rarely decidual cast. CASE: A 9-yr-old girl who was receiving depot medroxy-progesterone acetate [DepoProvera---JHH> to suppress menstruation passed tissue per vaginam. Pathological examination of the tissue showed a decidual cast with no chorionic villi, while a serum hCG test was also negative. CONCLUSIONS: Decidual cast formation is a rare side effect of progestogen use and should be considered in the differential diagnosis of passage of tissue per vaginam.

So AlwaysPeachy, your history of two casts is some what unusual. You are correct, the minipill, is composed of synthetic progesterone--but a very small dose. It is perhaps 1/10 the dose received in a day of DepoProvera. I honestly have not heard of any cases triggered by our current low dose combined contraceptive pills. I have not heard of any adverse impact of casts on conception or pregnancy. Nor have I any knowledge that a hormonal imbalance is a cause. A cast merely means the shedding of the uterine lining ("endometrium") in its progesterone influenced phase ("decidualized").

Hopefully you can find a GYN who can give you the benefit of their own experience with uterine casts.


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