This is a time when many women go through perimenopause, the years leading up to actual menopause. If you are trying to have a child, it could be increasingly difficult to become pregnant.

Women over 40 who do succeed in becoming pregnant are at a higher risk of experiencing complications before and during birth. This includes high blood pressure, diabetes, miscarriage, and various birth defects.

During perimenopause, your estrogen levels will fluctuate and cause your period to be lighter, heavier, shorter, or longer. The time between each period could also vary.

Some women only experience perimenopause for two years before they reach menopause, the stage in which you’ll cease menstruation and become infertile. Some other symptoms include hot flashes, fatigue, memory lapses, night sweats, and mood swings. 

Your metabolism slows as you age in general, but after 40 it becomes significantly harder to lose weight. Exercise is key, and combining weight-lifting with cardio is important. Try to shoot for 30 minutes of activity each day.

If you don’t eat well or exercise enough, you could readily gain more fat in the belly area. This increases your risk of heart disease, diabetes, and cancer.

Skipping meals will slow your metabolism, and when your metabolism is already slowing with age, it can have adverse effects on your health. Not eating causes your blood sugar to fluctuate and nearly two-thirds of adults with diabetes are diagnosed between ages 40 and 64 — so eat up.

Many women resort to following fad diets because it’s hard to keep off weight. But many lack the nutrients needed to preserve bone density and muscle mass. And don’t even think about crash dieting! Apart from becoming malnourished, you could also develop gallstones, dehydration, hair loss, and an abnormal heart rate.

Cutting carbs is often thought of as the quickest way to shed pounds, but fiber is really important for anyone over 40. Make sure you’re getting at least 25 to 30 grams of fiber every day by eating whole-grain bread, pasta, or oats. It’ll help to lower your cholesterol.

Egg whites may seem healthy because they have less fat and calories than whole eggs, but they also contain fewer nutrients. The yolk contains vitamins D, A, E, K, and B-12, which is necessary for adequate brain health. It also helps your blood flow properly.

Studies show that sitting all day can be as damaging to your health as smoking. Try using a standing desk at work, or make it a point to go for small walks throughout the day to avoid blood clots.

To keep your muscles flexible in old age, you need to stretch. Serious injuries can land you in the hospital and consequentially cause severe health problems down the road. The older you get, the harder it is to heal.

Washing your hands is important for people of all ages, especially after using the bathroom and before you eat. As you age, your immune system weakens and infections such as E. coli are easier to contract, and can be deadly to those who aren’t fully healthy.

It’s never too late to quit smoking cigarettes, even if you’ve been lighting up your entire life. Immediately after you stop, your blood pressure drops, your oxygen levels improve, and your risk of having a heart attack or developing heart disease declines.

Women in their 40s may begin to lose their cognitive abilities. With all the technology entertaining people today, reading books has become less common. Making a point to read something every so often will keep your mind sharp, and ward off brain degenerations like Alzheimer’s.

The word “fat” has a negative connotation to it, but eating them is actually a good thing. Foods like olive oil, salmon, and avocado can increase or maintain your cognitive function, keep your cholesterol down, and help you live longer.

Your dentist probably lectures you about the importance of flossing every time you have a visit, but she’s right. Flossing protects you from gum disease, which usually appears in people in their 30s and 40s.

If you have a family and a full-time job, making time for others can be hard. Loneliness can actually hurt your heart though, so for the sake of your mental and physical health, try your best to meet up with friends (or mom) when you can.

Women 40 and older are expected to get a mammogram every one to two years. This procedure tests for breast cancer, and can detect abnormalities up to three years before they can be felt.

Every day spent out in the sun unprotected might start to catch up to you. Have your doctor check for abnormal markings on your skin. If something looks fishy, a sample will be taken and sent to the lab. It could be melanoma or another form of skin cancer.

When you were younger, small aches and pains may have been nothing to write home about. Fast forward to your middle age, and those seemingly insignificant ticks may be warning signs for bigger issues at bay. Don’t ignore them! See your doctor if anything suspicious arises.

The fasting plasma glucose test measures blood sugar, which is an indicator of diabetes. Women usually start getting these blood tests every three years when they’re 45, but it’s suggested that they get one even earlier if they’re overweight, have hypertension, or have high cholesterol.

A woman’s risk for certain cancers including breast, ovarian, and uterine increases in her middle age.

In your mid 30s and early 40s, your body’s collagen production will naturally taper off. The rubbery protein gives structure to your skin cells, and is responsible for making it strong and firm. Without it, you will likely develop stretch marks and other cosmetic deficiencies.

Your vision begins to deteriorate after you hit 40. Your eyes lose elasticity and they become unable to focus. You might need to head to the eye doctor for some prescription lenses.

While most hearing loss occurs in the elderly, women in their middle age can experience it, too. Noises become muted when the hair cells in your inner ear are damaged or die. They don’t grow back, so the loss is permanent. Exposure to loud noises, family history, smoking, diabetes, and chemotherapy drugs can also play a role in hearing loss.

As women get older, their estrogen levels decline. Sufficient levels of estrogen account for a thick head of hair, so without much of it, strands can become thin, dry, brittle, or fall out altogether.

Lady parts will become dryer as women age. This could make sexual intercourse difficult and even painful. Vaginal dryness could make a woman more vulnerable to developing a urinary tract infection, too.

Even though menopause is linked to a decrease in sexual desire, some studies say that female libido is highest when a woman is in her 40s. One psychologist claims women become more interested in sex as their fertility comes to an end.

To hinder bone density loss, opt for strength training and extra calcium intake — about 1000 mg per day through supplements or three servings of dairy. You can also take a vitamin D supplement.

Heart disease has long been the number one killer of adults in the U.S., and women aged 40-59 are at a much greater risk than their younger counterparts. Symptoms can include chest pain, tightness, or pressure; shortness of breath; pain, numbness, weakness, or coldness in your arms or legs; and pain in the neck, jaw, throat, upper abdomen, or back.

The pigment cells in your hair follicles will start to perish, and the strands won’t be able to maintain as much melanin. This is why hair turns gray, silver, or white. But don’t worry, the color has been on-trend for years now. Just ask Judi Dench, Jamie Lee Curtis, Lady Gaga, and Ellie Goulding.

Wrinkles are likely the least surprising bullet on this list. They come naturally with age because the skin gets drier, thinner, weaker, and less elastic. People who don’t expose themselves to UV rays will be more protected from wrinkling.

If you’re not actively doing anything to keep your muscles in tight shape, they will likely begin to sag along with your skin. A woman’s breasts will also droop, because the breast tissue that helps maintain structure will start to give way.

Although it’s the largest organ, skin is the least likely to be properly taken care of. Take care of dry skin with lotion, and don’t forget to use a moisturizer on your face after washing it before bed.

Osteoarthritis is the most common form of arthritis. Pain generally affects the joints in your hands, knees, hips, and spine. This degenerative disease can happen at any age, but it’s more likely to occur in women in their 40s and 50s. Staying active and maintaining a healthy weight can slow the progression.

Uterine fibroids are noncancerous growths on the uterus. Size ranges from undetectable by the human eye to a bulky mass that can reach your ribcage. Symptoms include heavy menstrual bleeding for a long period of time, pelvic pressure or pain, frequent urination, difficulty emptying the bladder, constipation, and back or leg pain. This is most common in women in their 30s and 40s.

Not getting enough sleep can take a scary toll on your mental and physical health. Women in their 40s need seven to nine hours per night. To ensure a good night’s rest, stay on the same sleep schedule, keep your room dark, shut the TV off, and turn on the AC.

The way you metabolize alcohol will change. You’ll get a worse hangover and higher degree of toxicity from your drink. It’s best if you drink in moderation.

Who cares if you have wrinkles? You’re awesome! Regardless of all the potential woes on this list, one study says women 40 and older are actually more confident and depend on people less. Don’t we all aspire to feel this way? If you're nearing the next big birthday milestone — or you're already there — there are 50 things every woman over 50 should know about her health.

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