Pregnancy headaches are mainly due to the factors such as increased blood volume, hormonal changes and the initial stresses in the first three months. But usually poor posture is the main cause of pregnancy headaches in the final three months. Poor posture can usually result in pressure on the parts of the body and these discomforts are communicated with the brain and leads to pregnancy headaches

On the other hand, there are some migraineurs who report experiencing fewer pregnancy headaches. The hormones such as estrogen and progesterone in women mainly regulate the pregnancy and menstrual cycle.

These hormones also affect the chemicals in the brain that are related with the pregnancy headache. As the level of estrogen increases or decreases in the blood, the level of serotonin also changes accordingly. Serotonin is one of the brain chemicals, which helps to regulate the pain messages. The pregnancy headache improves when the estrogen level is high and headache become worse when the estrogen level is low. Estrogen level tends to increase rapidly and remains high throughout the pregnancy period. In this case, the pregnancy headaches improve or disappear.

Estrogen levels can be stabilized with the lactation. Lactation also increases the levels of other hormones that are related with the sensitivity of pain. The pregnant women need to be cautious about the headache medications during the breast feeding.

Most of the pregnancy headaches are occurring from causes that are not dangerous to the health. But the patient needs to consult the physician if the headaches get frequent or the patient experience swelling of the hands or face.

Sometimes, pregnancy headaches can also become a symptom for any other serious problem. Headache might be a sign of severe preeclampsia in the second or third trimester of pregnancy. Preeclampsia is one of the serious pregnancy-induced syndromes including protein in the urine, high blood pressure, and other changes. If the pregnancy headache occurs due to tension, the patients feels like compressing pain on the back of the neck or on both sides of the head.

Usually pregnancy headache disappears during the second trimester. This is due to the stabilization of the flood of hormones and the adaptation of body with the altered chemistry. At the first and last trimesters, pregnant women need to take some precautions to avoid such headaches. They need to consult their health care provider if the headache is sudden, explosive and includes a violent pain, which awakens from the sleep.

Pregnancy headache, which occurs with fever, stiff neck, nasal congestion, pain and pressure on the underneath of eyes, also needs consultation with a physician. All these factors show that pregnancy headaches need to be taken seriously than normal headaches.