Dear Doctor: I’m a healthy and active 42-year-old, but I’ve been noticing a change in my periods lately. They’re not as regular as before, and they’re a lot shorter. Could this be perimenopause? What’s going on, and what else is going to happen?

Dear Reader: Perimenopause is the transitional time that leads up to a woman’s final menstrual cycle. For some women, perimenopause can last for as little as a few months or a year. More often, it lasts for several years. In some instances, the changes associated with perimenopause can take place over the course of a decade. Although the symptoms can differ from woman to woman, they arise from the same cause. That is, certain hormonal changes within the body that precede the end of a woman’s reproductive years.

Perimenopause is the period of time during which a woman’s ovaries gradually begin to produce less estrogen, which is one of the hormones involved in the complex process that signals the uterus and the breasts to prepare for possible pregnancy. Although this shift in estrogen production is most common when a woman is in her mid-40s, it can happen earlier, when she is in her 30s. Perimenopause ends when a woman has gone a full year without a menstrual cycle, which is the start of menopause.

The symptoms that you mention are consistent with perimenopause. Many women experience changes to their menstrual cycles during this time, including fluctuations in flow, duration and regularity. These can be erratic because estrogen levels often diminish at an uneven pace, both rising and falling. However, it’s important to distinguish the normal changes that accompany the transition to menopause and symptoms that may signal other causes. If the changes that you see become extreme, such as persistent heavy bleeding, the presence of blood clots, spotting between periods or after sex, or an increase in frequency of menstruation, please check with your doctor. Other conditions such as fibroids, endometriosis or, rarely, cancer may be the cause.

The final phase of perimenopause sees the sharpest drop-off in estrogen production. This is a time during which additional symptoms often appear. These can include fatigue, breast tenderness, changes to mood, hot flashes, a worsening of the symptoms of PMS, urinary incontinence, night sweats, sleep disruption, vaginal dryness and changes to sex drive. This decline in estrogen leaves women at risk of osteoporosis, a disease in which bones gradually become porous and, thus, more fragile. Women also begin to lose the protective heart effects of estrogen, which is believed to help keep blood vessels more flexible.

Considering your age, along with the symptoms that you mentioned, it’s possible that you are experiencing perimenopause. However, due to the ongoing fluctuations in hormone levels, no one test can provide a definitive diagnosis. Instead, your health care provider will evaluate your symptoms, along with your age and menstrual history. If your symptoms begin to interfere with quality of life, they may offer treatment that can include lifestyle changes, hormone replacement therapy or antidepressants. Each has risks and benefits, so be sure to have these explained to you in detail.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: It seems like gut microbes are part of every kind of health issue now. I just read that having the wrong bacteria causes pulmonary hypertension, which is something our dad had before he died. Is that really true? How can it be fixed?

Dear Reader: We’re right there with you in being amazed by the breadth and depth of the role of the gut microbiome in health and well-being. The emerging research these days is fascinating, and it continues to shape and expand our understanding of how the body functions. In your question, you’re referring to the results of research published last February in the American Heart Association’s journal Hypertension. According to the study, researchers found that a specific assortment of gut bacteria may not only contribute to a certain type of pulmonary hypertension, but also may be useful in predicting its onset.

Let’s start by talking about the condition itself. When someone has pulmonary hypertension, it means that something has caused high blood pressure in the arteries of their lungs. This is in contrast to general hypertension, which is high blood pressure in the arteries throughout the body. The study that you’re asking about focuses on a specific subset of the disease, known as pulmonary arterial hypertension, or PAH. That’s when progressive scarring damages the walls of the small arteries within the lungs, which makes them stiff and narrow and slows down blood flow. As blood pressure rises, the right side of the heart has to work harder. Over time, this extra workload taxes the heart and causes it to become enlarged and weakened, which leads to a new set of problems.

Symptoms of PAH include fatigue, shortness of breath, heart arrhythmias, and swelling in the feet, legs, abdomen and neck. Although the condition can arise on its own, it has been associated with congenital heart disease, COPD, chronic liver disease and drug use.

PAH is a serious and progressive disease, and there is no known cure at this time. Because the symptoms are common to many conditions, it can be hard to diagnose in its earliest stages. When PAH is suspected, diagnosis begins with blood tests, chest X-rays, scans of the heart and lungs, and endurance tests. The condition is confirmed with a procedure known as right heart catheterization, which allows a direct measurement of blood pressure within the main pulmonary arteries. Treatment focuses on managing symptoms with blood thinners, diuretics and supplemental oxygen.

The new PAH findings hint at a radical new approach to the disease. In the study, researchers analyzed stool samples from 18 PAH patients and 12 people with no history of cardiopulmonary disease. They were surprised to find the PAH patients’ microbiomes harbored a specific collection of bacteria that were absent in the stool of the healthy test subjects. According to the study results, the presence of those specific bacteria predicted a diagnosis of PAH with 83% accuracy. It’s a small study, and many questions remain. But if the results are corroborated in future research, this new direction holds promise for new avenues in PAH diagnosis and therapy.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Hello, dear readers, and welcome to this month’s letters column. In the midst of so much turmoil and uncertainty, we’re more grateful than ever for this chance to communicate with you.

-- Several of you wrote about the frustration of seeing someone exit a public restroom without washing his or her hands. “I find this upsetting at the best of times, but during the COVID-19 outbreak, I am more concerned than offended. What can be done?” a reader asked. Unfortunately, you can’t force people to practice good hygiene. However, you can take steps to protect yourself from the effects of their bad habits. Push swinging doors open with a shoulder, elbow or knee. Use toilet paper or a paper towel to protect yourself from any surfaces that you have to touch, such as the lock on the stall door, faucets on the sink and the door handle on the way out. Don’t rest personal items, such as a purse, on a public bathroom countertop. Be sure to dispose of the used barrier paper safely in a trash can. And, of course, wash your hands.

-- On the topic of hand-washing, we received a lot of mail asking about the effectiveness of hand sanitizers. The short answer is that 20 seconds of thorough hand-washing with soap and water is the preferred method of protecting against all types of germs and microbes. However, when this isn’t possible, an alcohol-based hand sanitizer of at least 60% concentration is a good alternative. The problems arise when people fail to use a large enough volume of hand sanitizer, or when they wipe the product off of their hands before it has completely dried. The takeaway here is to use the proper-strength products and read and follow the directions.

-- In that same vein, some of you told us you are confused that hand sanitizers, which are marketed as antibacterial, are being recommended for use during a virus outbreak. The answer is that hand sanitizers do not target a specific microbe; they work by damaging the exterior membranes of a wide range of organisms. This includes bacteria and some viruses. Although not all viruses have an exterior membrane, the coronavirus does, so hand sanitizers are useful at this time. However, as we noted, the proper alcohol concentration is crucial to the work of destroying the membrane, so use the right product and follow the instructions.

Thank you to everyone who has written with kind words. Knowing that these columns are useful means a lot to us. (And to Glenda in Tulsa, who just turned 83, your note about who you want to be “when I grow up” made us laugh out loud.) We appreciate the time and care you all put into your letters and emails, and we will revisit some topics with your thoughtful suggestions in mind. We look forward to our next batch of mail and to seeing you here again next month. Please take care of yourselves -- and stay safe.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)