Estrogen Therapies Are Not All the Same

Q:  I am a 52-year-old female, currently undergoing hormone replacement therapy. Previously, when I was on Loestrin, I had no side effects, other than my blood pressure being raised about 40 points and having to take high blood pressure medication for this problem.

Since that time, I have tried several months on both Prempro Blue and Prempro Pink, and am currently in my second week of trying Ortho Prefest.

With all of these products, I have had varying degrees of breast tenderness, but more distressing symptoms have been severe cramps, bloating and backache. Why have these hormones produced such painful side effects, when the Loestrin did not?

A:  First of all, the amount of estrogen in Loestrin (a birth control pill) is probably 10 times as much as in the Prempro (hormone replacement pills for menopause). Birth control pills suppress your ovaries so they don't produce many hormones, whereas your ovaries may still be working with hormone replacement therapy doses.

All estrogens are not created equal. This will probably come as a surprise to many women, and even as a physician, it's something I've learned about only recently. Loestrin contains a specific type of estrogen (ethinyl estradiol) and progesterone (norethindrone). Prempro is a combination of conjugated estrogens (many types), derived from the urine of pregnant horses (hence the name, Premarin), and progesterone in the form of medroxyprogesterone acetate.

Julianne Newcomer, MD, Associate Professor of Obstetrics and Gynecology at the Medical College of Wisconsin, suggests that you might want to try Femhrt or Activella. These are two new brands for hormone replacement that contain estradiol or ethinyl estradiol and norethindrone, the same hormones found in Loestrin. She has also found that patients have less breast tenderness when using estrogen patches rather than pills, so that would be another possibility for you.

"Dear Doctor" is a compilation of patient questions answered by doctors from the Medical College of Wisconsin.