DEAR DR. DONOHUE: My older sister had a strep infection when she was pregnant with her first child. They told her that the infection could be deadly to her baby. I am pregnant. I had strep throat when I became pregnant. Does this carry the same danger that my sister’s strep infection carried? – C.R.

You can relax. Your sister’s infection was not a strep throat. She had a special kind of strep, a group B strep, in her birth canal. The strep that causes strep throat is a group A strep. The two germs have the same last names but entirely different significance.

Group B strep hardly ever cause problems. However, during pregnancy, when it resides in the vagina, it can be a great danger for the baby. The baby can pick it up during its passage through the birth canal. Infant infections are a threat to life. The strep can infect the baby’s brain coverings – meningitis. It can infect the lungs – pneumonia. And it can get into the infant’s blood – sepsis.

In the 1970s, when there was not too much information about the infection, 50 percent of infected infants died. In the 1990s, when there was much more information about this germ and when there were good tests to detect it before delivery, infant mortality from this strep infection fell to less than 15 percent.

Now almost all doctors check their pregnant patients for the presence of group B strep between the 35th and 37th weeks of pregnancy. If the mother-to-be harbors strep in the vagina, antibiotics are given prior to and during delivery. This has cut, by 70 percent, the number of newborn infections.

DEAR DR. DONOHUE: Two weeks ago, I happened to look in the mirror after taking a bath. I saw a large black spot on my back. I thought for sure it was a melanoma, and I made an appointment with my doctor. She examined me and said that it isn’t a melanoma; it’s a seborrheic keratosis.

I was so relieved to hear it wasn’t cancer that I forgot to ask some questions I would like answered.

How did I get it, and how should it be treated? The doctor didn’t suggest any treatment. – R.W.

Most adults have at least one seborrheic keratosis. Some have many. They’re oval patches that vary in diameter from one-third inch (0.12 cm) to, rarely, as large as 3 inches (7.6 cm). Their color ranges from tan to black. Their surfaces look sort of crusty, and the whole affair appears to be glued to the skin.

Mainly they’re found on the chest, back, neck and face. An occasional one itches. They mostly appear during middle age.

Seborrheic keratoses are not cancer and don’t become cancer. The cause for them hasn’t been found.

People often think they’re melanomas, the most deadly skin cancer. Doctors can usually identify them correctly with an eyeball inspection. You were quite smart in taking yourself to the doctor. Any dark skin patch that’s suspicious merits a doctor’s appointment. Melanomas kill.

If you don’t want the thing treated, it doesn’t have to be. If you’d like to get rid of it, a doctor can freeze or scrape it off, or do both.

DEAR DR. DONOHUE: I am 79 and in great health. I don’t take a single medicine. I work 40 hours a week. But one thing does puzzle me. All my life, doctors haven’t been able to take my blood pressure in my right arm. Now I tell anyone taking my pressure to use my left arm. What’s wrong with my right arm? Why can’t the pressure be detected there? – A.L.

You can be sure, after living 79 years of good health and never having had any symptoms in your right arm, that the inability to hear blood pressure there is nothing more than a curiosity. The main artery in that arm might take a different path on its way to the hand than it does in most people.

This isn’t something to lose sleep over.

DEAR DR. DONOHUE: What’s the meaning of “MCV” and “MCH” on a blood report? – G.T.

ANSWER: “MCV” is “mean corpuscular volume,” the average size of red blood cells. “MCH” is “mean corpuscular hemoglobin,” the average content of hemoglobin within red blood cells. The values aid in determining what kind of anemia a person has.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from

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