Experiencing heart palpitations and shortness of breath during pregnancy is common. However, it is important to understand why this occurs and what you can do to relieve the discomfort.
What Causes Heart Palpitations During Pregnancy?
You may experience heart palpitations during pregnancy because your body has a significantly larger amount of blood – up to 25% – which means that your heart needs to beat faster and harder. This increased strain on the heart can often lead to palpitations, which feels as though your heart is fluttering or beating extremely quickly. This can be frightening for many and may result in lightheadedness, but this will usually pass.
Heart palpitations can also arise if you are suffering from excess anxiety, pre-existing heart conditions, consuming stimulant chemicals such as caffeine, and using certain medications. While these palpitations are considered normal, if you experience difficulty breathing, coughing up blood or severe tightness or pressure in the chest, you should seek medical attention immediately. 
Causes of Shortness of Breath During Pregnancy
One of the common symptoms of pregnancy, particularly in the first trimester, is shortness of breath. In early pregnancy, the body responds to a huge rush of hormones, including progesterone, which can affect the functioning of your lungs. Basically, your body needs more oxygen because the body demands more resources, which means that you will inhale and exhale forcefully at times. In the first few months, as you adjust to this new situation, it can cause the feeling of shortness of breath. 
Furthermore, as the growing baby puts additional pressure on the diaphragm, it can also cause shortness of breath or a sensation that you can’t get enough oxygen. If you have other medical conditions such as asthma or high blood pressure, it can also create shortness of breath. Similar to heart palpitations, shortness of breath in pregnancy is quite common, but it can signal a more serious problem too. Respiratory complications can make delivery dangerous, and raise the chances of a blood clot, so serious shortness of breath should be discussed with your doctor. 
The best ways to manage heart palpitations and shortness of breath during pregnancy include managing your stress, wearing loose clothing, lying down, drinking water and avoiding stimulants.
Working to lower your anxiety levels is an excellent way to soothe heart palpitations and shortness of breath during pregnancy, as an excess of stress hormones can increase blood pressure. 
If you lie down on your left side, it can help to slow your blood pressure and allow the circulatory system to rest. While this is primarily for heart palpitations, it can also help to relax your body and regulate breathing.
Staying hydrated will help to regulate your blood pressure, which will lower your risk of suffering from heart palpitations. This can also calm your nerves and allow you to breathe normally. 
Do your best to avoid stimulating beverages such as coffee, particularly if you suffer from heart palpitations frequently during pregnancy. This can also help to relieve many respiratory issues and lower blood pressure. 
Wearing Loose Clothes
Tight or restrictive clothing can raise your blood pressure, body temperature, and increase sweating. This can increase your stress hormone levels and may contribute to shortness of breath during pregnancy. Loose and comfortable clothing is a better option for pregnancy, particularly in your third trimester. 
Word of Caution: While heart palpitations and shortness of breath during pregnancy are not necessarily a reason to rush to the hospital, they should be taken seriously, particularly if they are too frequent or occur in a more severe way than you are used to experiencing them. For example, if you feel tightness in the chest or have difficulty breathing, seek medical attention. Any other secondary symptoms of the circulatory system such as blue-tinged fingers, paleness, excessive sweating or the sensation that you may faint, should be taken very seriously.