1) This is in reference to your Missed periods Q&A. Another cause of missed or late periods is PCOS (polycystic ovary syndrome). A lot of health care providers don't seem to be aware of this syndrome. In this syndrome, missed or irregular periods are caused by unusual hormone levels, sometimes in combination with insulin intolerance. Because missed and irregular periods cause scar tissue build-up in the uterus (which may cause endometrial cancer) and may cause infertility, it is important that your readers know to ask their health care provider about this syndrome. There are obviously other symptoms and complications, but I just thought that I might mention it to you so that you might read up on it for your readers. Thank you.

2) I was recently diagnosed with polycystic ovary syndrome (PCOS). I'm only 17 and am afraid that this will affect my chance of having children. Should I worry? Also, I know birth control pills will help me regulate my period, but if I take them, will it stop the effects PCOS has on me? Like me gaining rapid weight, missed periods, and losing my hair? This is really worrying me. Can you inform me on this syndrome?

Recently I bought a sun protection cream from a health food store. The cream claims to provide sun protection (it's labeled SPF 15) by a plant complex made of PABA, willow bark extract, myrtle and myrtus leaf extract. It says that myrtle and myrtus leaf help protect from both UVA and UVB.

My questions are as follows:

1) Can this PABA complex provide the sun protection it claims (SPF 15 for both UVA and UVB rays)? The reason I am asking this is because until now I had only heard of sun protection by titanium dioxide or chemicals like octyl mexaoxycinnamate (did I get it right?). So I am curious to find out.

2) I notice a slight burning sensation in my eyes after I apply the product on my face. Is it true that PABA is a common irritant? (Since I notice many products proudly claiming PABA-free I wonder if it's really not good for you.)

Please help. I hope this question falls within your realm of expertise. After all, you are the 'know it all' around here, aren't you?

Someone told me that ChapStick was addictive and the way I'm going through it, I believe them. Is it truly addictive? Can I get help?

I have a friend who will be going through chemotherapy and radiation. What can she do to build herself up to keep her body in the best condition possible?

Ever since high school, I've had very oily hair and skin, but it became worse in college. Now I'm in my mid-twenties and have to shampoo my hair about 10 times each day to get it clean. Then by evening it's already oily again. This isn't my scalp trying to moisturize itself after being over cleaned, because I've tried not washing it completely and it's even oilier the next day.

Are there any special shampoos or medications that help reduce oily skin? I've tried some facial products from my dermatologist, but they haven't reduced the oil production. This is an embarrassing problem and limits the overnight activities I can do, like camping or staying with friends.

I've come down with chickenpox. Should I stay home from classes even though 90 percent of adults have already had it and are thus immune? If I take great care washing my hands and avoiding coughing anywhere but into the crook of my arm, will I be reasonably assured of not spreading it?

I have an invisible disability and I'm really getting into disabilities activism. Even in liberal circles ableism is still pretty accepted and this upsets me. However, when I try to educate people around me, it sometimes goes awry. I had one friend get upset when I called her out for using the word "retard." Another got upset when I pointed out that her Facebook post of inspirational people with disabilities (that just showed people with disabilities doing normal things) was a little offensive and tried to tell her about "inspiration porn." I get that using the word "retard" is normal as is "inspiration porn." I just don't think it should be.

I know my friends are caring, socially conscious people. I expect people to be a little upset, but ultimately I would also expect them respect the fact that it's really not OK to objectify people with disabilities in the way that inspiration porn and the use of words like "retard" do. What I want to know is how do I point out that people are expressing a harmful social bias, without having them get so upset that they write me off as an over sensitive concern troll?

Is there any cure for itching when I wear wool clothes? In the winter time, I love to wear my wool pants and sweaters, but they make me itch. I've tried wearing pantyhose underneath, but it doesn't work.

Help.

I have two piercings in each earlobe; however I have not worn earrings in the second set of holes for several years. Recently I tried to insert earrings into the seldom-used pierce holes. One earring went in with no problem, but the second did not go through after several attempts (I actually gave up because my last attempt bent the earring post). I have tried inserting other earrings but they also will not go all the way through. Is this something I can fix myself? Do I have to get the same hole professionally re-pierced? Will there be problems with scar tissue at the site?

I am African-American, but my skin is not that dark. I was never told that I needed sunscreen and when I worked in a daycare I was told in a very delicate manner that only the paler children needed sunscreen. I've been out in the sun for extended periods of time and was wondering if sunscreen is necessary for someone of my complexion. If so, what strength?