Ask the doctors: Good sleep hygiene is key for sleeping on a plane

Q: We are flying overseas, and although I would love to snooze through most of the 15-hour flight, I'm generally not able to sleep on a plane. Melatonin doesn't work for me. I've taken Ambien in the past, but I'm concerned about the negative effects I've read about. Do you have any advice?

A: Long-haul flights can be arduous. Unless you've splurged on the pricey luxury of lie-flat seats, you're faced with sleeping conditions that are less than optimal. This includes being packed into close quarters and being seated upright with limited legroom and minimal privacy. Add in the 75 to 85 decibels of ambient aircraft noise - that's in the neighborhood of a hair dryer or a vacuum - and falling asleep becomes a real challenge.

Some travelers swear by melatonin, a hormone secreted by the brain in response to darkness. Melatonin influences the rhythms of the internal 24-hour clock, and it plays a role in preparing the body and brain for sleep. While melatonin can be helpful in setting the stage to slip into sleep, it does not act as a sedative. That effect is conferred by prescription sleeping medications.

Prescription drugs can induce sleep, but they have potential side effects. These include lingering dizziness, fatigue or grogginess upon awakening. Some types of prescription sleep medications can result in abnormal sleep-related behaviors, such as sleepwalking.

Although occasional use is considered to be safe, these drugs have addictive and abusive potential and should be taken with caution.

If someone opts for a sedative, we encourage using a trial dose at home, prior to the flight, in order to ensure tolerance. Anyone using a sleep medication should time the dose in order to have a few waking hours at the end of the flight. This provides a window of time to recover from any grogginess or other possible aftereffects.

Whenever discussing sleep, it's important to remember that the physical environment plays a role. Dress in comfortable, loosefitting layers, as plane interiors have wide swings in temperature. Studies show that swapping your shoes for a pair of thick, warm sleep socks can speed the onset of sleep and help you sleep longer.

Ear plugs or noise-canceling headphones to mitigate engine noise, along with a well-fitted sleep mask, improve your chances of dropping off and staying asleep. Lavender oil, which is soothing and calming, has been found to increase slow-wave sleep. That's the refreshing deep sleep we all hope for.

Given the limited degree that most aircraft seats can recline, passengers need to get creative about finding a comfortable position. This includes using a neck pillow that will provide complete support and keep your head from bobbing. Creating a footrest with a carry-on or other device can not only ease discomfort, but it can help prevent blood clots.

Standard sleep hygiene also applies. That means abstaining from screens, caffeine and alcohol, each of which can interfere with the onset of sleep, and also sustained sleep. And when you're not asleep, remember to get up periodically to walk and stretch, and to counteract the dry airplane air by drinking plenty of water.

Q: If my doctor won't order a PSA or other screening test, can I pay for it myself? We are always told about the importance of early detection. So why aren't screening tests recommended for seniors? I get a more comprehensive overview of my car's health when I get an oil change!

A: A screening test is used to determine if someone who is asymptomatic has developed a disease or condition. The intent is to identify a medical issue at an early stage, when treatment is more likely to result in a positive outcome. This may be curing the disease or managing it to improve longevity and quality of life.

Health data show that these types of screenings can save and extend lives. But it's important to note that the guidelines for these tests are only that - guidelines. They are not hard and fast rules. Rather, they are recommendations based on the analysis of a complex range of scientific data.

How, when and by whom a screening test is used depends on each individual person. The decision takes into account someone's general health, their medical and family histories and age. It also includes the determination of whether the test itself may lead to potential harm. This includes stress and worry, physical harm, inaccurate results and unneeded follow-up tests or procedures.

Older adults are often living with health conditions that make treating a disease, such as cancer, its own health risk. When this is the case, certain types of screening tests are recommended only when the potential benefits outweigh the potential harms.

The prostate-specific antigen (PSA) test you mention falls into that category. While effective at detecting certain hormonal changes that occur when someone has prostate cancer, it can return false positive results. The PSA test has been overused in the past, which has led to unnecessary, and possibly harmful, treatment.

The current recommendation for men between the ages of 55 and 69 is to decide on the use of a PSA test on a case-by-case basis. That means evaluating someone's general health, their risk for prostate cancer and their ability to move forward with further testing and treatment if needed. Here at UCLA, for example, we recommend that Black men of all ages, who are at increased risk of developing prostate cancer, work with their doctors to tailor PSA testing to their unique and specific needs.

When working with our own patients, we have in-depth discussions about the potential risks of the test versus the possible benefits. We view our relationships with our patients as a coaching partnership rather than a paternalistic one. We believe strongly in shared decision-making. Some patients, after learning the risks, decline the test. Others enthusiastically accept it.

It is possible to find a lab where you can order your own PSA test. However, we think your energies are better spent looking for a different doctor. Find someone who is willing to let you share in these important health care decisions. That you feel your mechanic offers better care than your current doctor says a lot about that relationship. We think you can find a better match.

Q: Can you please talk about placenta accreta? It happened to my sister, and she had serious medical issues when she had her baby. How can you know that you have it? Does it run in families? My husband and I are ready to start our own family, but this has me scared.

A: Let's begin with the placenta, which is a temporary organ that forms in the uterus over the course of a pregnancy. It serves as the medium through which oxygen and nutrients pass from the mother to the developing baby. The placenta also performs a wide range of complex functions that, once the baby is born, will be carried out by other organs and structures. These include the lungs, liver, gastrointestinal tract, kidneys and endocrine system.

During the first trimester of pregnancy, the placenta forms gradually. In the second trimester, its growth parallels that of the baby. Although it continues to develop in the third trimester, its growth slows significantly. By the time the baby reaches full term, the placenta is a spongy disc of tissue 8 to 10 inches in diameter, about an inch thick and weighs about 18 ounces. In order for a pregnancy to be successful, and to result in a safe delivery, proper development of the placenta is essential. This includes not only the physiological structure of the organ, but also its position and placement within the uterus.

The term placenta accreta refers to a serious pregnancy complication in which the placenta becomes too deeply attached to the wall of the uterus. This can lead to a preterm delivery, and it can cause excessive bleeding during pregnancy, labor and following the birth. The degree of penetration into the lining of the uterine wall can prevent the smooth separation of the organ that occurs during delivery in a normal pregnancy.

A hysterectomy is often required to save the mother's life. Risk factors include previous cesarean section, previous uterine surgery and older maternal age. There is no evidence of a genetic component, or that the condition runs in families.

Placenta accreta often occurs without symptoms. In some cases, it can cause certain changes to maternal blood profiles, but these are not reliable indicators. A study published in 2020 suggests there may a biomarker associated with the condition. However, more research is needed for this to be developed into a test. As a result, there is no blood test for the condition at this time. It can sometimes be spotted in the course of imaging studies, most often with an ultrasound.

Due to the cycle of placental growth that we described, diagnosis commonly takes place in the second or third trimester of pregnancy. When the condition is discovered, a planned C-section is often recommended. If someone is at risk of placenta accreta, it is recommended they seek care with an OB-GYN with experience in the condition and plan delivery in a facility with a robust blood bank.

For women at risk, the National Accreta Foundation (preventaccreta.org) is a good resource.

• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.