For many women, headaches during pregnancy are difficult to avoid and can make the stress and challenges of pregnancy even more pronounced. These headaches may be minor annoyances or can become debilitating in nature. Some women complain of these headaches throughout their term, while others say that the headaches are more common in the first and third trimesters.
Clearly, there is some variability in this condition, but since so many women experience headaches during pregnancy, there is quite a bit of anecdotal evidence and research on the subject. If you are pregnant or looking to have a child in the future, it is important to understand the causes of this condition, as well as potential treatments and home remedies. 
Causes of Headaches During Pregnancy
There are many potential causes of headaches during pregnancy but the most known are a poor body posture, imbalanced hormones, changes in blood volume and a lack of sleep, among others.
Hormonal Changes: During pregnancy, your body experiences a rush of hormones that can change your metabolism, mood and bodily processes in many ways. It can also lead to an increase in headaches, as the body attempts to re-balance its hormone levels. For example, a rush of progesterone in the body, particularly in the first trimester, may cause the blood vessels in your head and womb to relax. So, when the blood rushes in to fill that space, it can cause an acute headache. 
Posture Issues: As your body changes during pregnancy, your posture is inevitably affected, which can put pressure on your back, neck, spine, head, and shoulders. Even these slight changes in posture can cause muscle tension, which can lead to a headache. 
Blood Volume: As mentioned above, hormones can cause changes in the blood volume due to the relaxing effect certain hormones have on hypertension. Any changes in blood pressure, both dropping and rising, can result in quick and painful headaches that can be difficult to handle.
Sinus Congestion: Your immune system may be weak during pregnancy, as your body is devoting so many resources to develop a healthy fetus. This can make it easy to suffer from sinus infections and other common illnesses, which can increase pressure in the sinus cavities and lead to headaches. 
Sleep Quality: When you are pregnant, you may find it difficult to get a full night’s sleep, as you may be uncomfortable or may need to switch positions quite often. A lack of sleep can lead to exhaustion and is one of the most common causes of headaches during pregnancy. 
Preeclampsia: This is a serious condition of high blood pressure that can affect women and pose a threat to a healthy pregnancy. A headache is the most notable symptom of this condition. If your headaches don’t respond to home remedies or basic medications, consult your doctor. 
Stress Levels: Stress and anxiety may seem like natural emotions during pregnancy. An increase in stress hormones in the body can not only lead to inflammation and headaches but can also be harmful to your unborn child.
Are Headaches During Pregnancy Common?
Experiencing an increase in headaches during pregnancy is completely common. It can be worrying to suddenly experience more headaches than normal, they pose a very little risk, and are generally considered an annoyance more than a health concern. In fact, some women who regularly suffer from migraines find an improvement in this condition during pregnancy.
That being said, headaches can still be debilitating and painful. Severe or chronic headaches can be a sign of a more serious underlying condition and should be checked out by a doctor. Fortunately, there are a number of effective treatments for headaches during pregnancy to relieve this discomfort.
Some of the most effective treatments for headaches during pregnancy include the use of certain painkillers and cold compresses, among others.
Taking medication during pregnancy is something that should always be discussed with your doctor beforehand. However, acetaminophen is usually considered safe for pregnant women. This medication can reduce inflammation in the capillaries and thin the blood to lower your blood pressure and relieve pain. Drugs like ibuprofen and aspirin, are not always safe and should be avoided unless specifically prescribed by a doctor. 
In the case of headaches during pregnancy, a cold compress can be applied to the temples, back of the neck or forehead to reduce tension in those areas. The cold temperature can also reduce inflammation and swelling, which can quickly reduce a headache. 
Home Remedies & Therapies
There are quite a few home remedies and natural treatments for headaches during pregnancy, such as optimizing your diet, getting more physical activity, taking enough time to relax, steam inhalation, closing the blinds, and the use of spinach, peppermint oil, and omega-3 fatty acids.
Breathing deeply over a pot of boiling water can help to ease pressure in the sinuses and reduces inflammation. This can soothe the mind and body and even lowers blood pressure in some cases. 
Staying active while pregnant may seem difficult, but it is important to keep your blood flowing and enjoy the release of feel-good hormones, like dopamine and serotonin, which can counter the effects of headaches.
Omega-3 Fatty Acids
These “good” forms of fat are well known to reduce inflammation in the body and reduce the occurrence and severity of headaches. Ask your doctor about omega-3 supplements or whether adding fish to your pregnancy diet is appropriate. 
The relaxant and anti-inflammatory nature of peppermint oil can quickly relieve discomfort and ease the mind and help you sleep. A few drops on your pillow should do the trick. 
Some pregnant women become very sensitive to sunlight, which causes squinting, tension in the temples, and a much higher risk of headaches. Wear sunglasses or sit in a darkened room to give your eyes a break. 
One of the best foods to eliminate headaches is spinach, as it is rich in magnesium, a key pregnancy mineral. It also helps the body to monitor blood pressure, while soothing the body and increasing the release of “feel-good” hormones. 
Prevention of Headaches During Pregnancy
If you want to be proactive and avoid headaches before they ever develop, some excellent techniques include improving your posture, trying relaxation techniques, avoiding headache triggers and weaning yourself off of sugar and caffeine.
Try yoga or meditation in your first trimester and you will experience fewer headaches, as these practices soothe both the body and the mind. 
Sitting up straight is critical for avoiding headaches, as is wearing the right shoes, avoiding uncomfortable furniture, and not sitting in the same position for too long.
There are plenty of headache triggers for every individual, such as specific foods, activities, movements or postures. Constantly monitor your personal triggers and avoid them gradually, if not at once.
Avoid Sugar & Caffeine
Cutting out excess caffeine and sugar from your diet is a good choice as a pregnant woman, but going “cold turkey” can result in withdrawal symptoms, including severe headaches. Gradually weaning off of these substances during pregnancy is highly recommended.