CAN HCG CAUSE HEADACHES?

Human chorionic gonadotropin, or hCG, is a hormone that plays a crucial role in pregnancy and fertility treatment. It supports the production of progesterone, which helps prepare the uterine lining for implantation and maintain early pregnancy.

While hCG is vital for reproductive health, changes in hormone levels can sometimes trigger unwanted symptoms. One of the most common and uncomfortable of these is headache. Many people notice mild to moderate headaches when hCG levels rise, either naturally during pregnancy or as a side effect of hCG injections used in fertility treatment.

A hCG blood test is the most accurate way to measure your hormone levels, helping you understand whether hCG is contributing to how you feel.

hCG is produced by the placenta shortly after a fertilised egg attaches to the wall of the uterus. Its main role is to maintain the production of progesterone during early pregnancy. Progesterone keeps the uterine lining thick enough to support a growing embryo.

In fertility treatment, synthetic hCG is sometimes used to trigger ovulation or support the early stages of conception. Because hCG interacts closely with the body’s hormone receptors, changes in its levels can cause temporary side effects as the body adjusts.

When hCG levels rise, the body responds in several ways. It increases progesterone and oestrogen production, alters blood flow, and affects how fluids are distributed throughout the body. These rapid hormonal changes can lead to short-term effects such as fatigue, nausea, and headaches.

During early pregnancy, hCG levels double roughly every two to three days. This sharp increase can cause the body to retain more fluid and affect blood vessel tone, both of which may contribute to headaches.

Yes. Both natural and medically administered hCG can cause headaches. These headaches are usually mild and short-lived but can feel similar to tension or hormonal headaches.

When hCG is used as part of fertility treatment, headaches can appear within hours or days of the injection. During pregnancy, they are more likely to occur in the first trimester, when hormone levels are rising most rapidly.

In most cases, hCG-related headaches are not harmful. They are simply a sign that your body is responding to changes in hormone balance.

Headaches are a common symptom in early pregnancy. As hCG levels rise, the body experiences a surge in other hormones such as oestrogen and progesterone, which can affect blood vessels and the nervous system.

Other factors that can make headaches worse in pregnancy include:

• Dehydration
  
  

• Low blood sugar from skipping meals
  
  

• Fatigue or lack of sleep
  
  

• Stress or tension
  
  

• Caffeine withdrawal
  
  

Headaches tend to be most common during the first trimester and often improve as pregnancy progresses. If you are pregnant and experiencing frequent headaches, it’s a good idea to discuss them with your midwife or GP to rule out other causes.

If you are undergoing fertility treatment, you may receive an hCG injection to stimulate ovulation or support implantation. These treatments temporarily raise hormone levels to mimic natural reproductive changes.

Headaches are among the most common mild side effects of hCG medication, alongside tiredness, bloating, and breast tenderness. The cause is thought to be the sudden rise in hormones, which can affect blood vessel dilation and fluid retention.

These headaches usually resolve within a few days of treatment. However, if you are taking other fertility medications, such as gonadotropins, the combined hormonal effects can sometimes make symptoms stronger.

Most hCG-related headaches can be managed safely at home. Here are some practical tips to relieve discomfort:

• Stay hydrated: Dehydration can make hormonal headaches worse. Drink water regularly throughout the day.
  
  

• Eat small, frequent meals: Keeping your blood sugar steady helps reduce headaches caused by hunger or dips in energy.
  
  

• Rest and manage stress: Relaxation techniques such as gentle stretching, deep breathing, or meditation can help ease tension headaches.
  
  

• Avoid strong lights and screens: Bright lights can worsen hormonal headaches. Try resting in a dim room.
  
  

• Use a cold compress: Placing a cool cloth on your forehead or neck can help relieve pressure and pain.
  
  

• Avoid caffeine withdrawal: If you regularly drink tea or coffee, cutting down too suddenly can cause headaches. Reduce your intake gradually.
  
  

Always check with your doctor or pharmacist before taking pain relief such as paracetamol or ibuprofen during pregnancy or fertility treatment.

Although headaches are common during hormonal changes, you should speak to a healthcare professional if you experience:

• Severe or persistent headaches that don’t improve with rest or hydration
  
  

• Visual disturbances such as flashing lights or blurred vision
  
  

• Swelling in the hands, feet, or face
  
  

• Dizziness, nausea, or vomiting that worsens
  
  

These symptoms may indicate conditions such as pre-eclampsia, which require prompt medical assessment.

If you are taking fertility medication, always inform your clinic about any severe or unusual side effects. They can adjust your treatment plan or recommend further testing if needed.

If you’re unsure whether your symptoms are related to hCG, a simple blood test can confirm your hormone levels.

An hCG blood test measures the exact concentration of the hormone in your bloodstream and can help:

• Confirm pregnancy earlier than a home test
  
  

• Monitor hCG changes over time
  
  

• Detect possible complications such as ectopic pregnancy or miscarriage
  
  

• Track fertility treatment response
  
  

At One Day Tests, results are available online within 24 to 48 hours and reviewed by an accredited UK laboratory.