How pregnancy can affect your heart health
Pregnancy complications - including gestational hypertension, preeclampsia, gestational diabetes, extremely low birth weight, and preterm birth - are associated with an increased risk for heart disease, heart failure, and stroke later in life.
One of the more common complications is preeclampsia, a pregnancy syndrome that results in high blood pressure and often accompanying organ damage. Preeclampsia is on the rise, and is one of the leading causes of preterm birth and major health complications for mothers and babies. Above and beyond the immediate concerns during pregnancy and immediately postpartum, pregnancy related high blood pressure and preeclampsia increase the risk of future heart disease in the mother by as much as 2 to 4 fold. Given that hypertensive disorders affect up to 10% of pregnancies, this is a major risk factor for future heart health in many women. Let’s review
What is pre-eclampsia?
Pre-eclampsia is characterized by high blood pressure that occurs during pregnancy (starting after 20 weeks) as well as either protein in the urine, or evidence of damage to the kidneys, damage to the liver, low platelets, or neurologic complications. If the blood pressure is very high (the top number > 160 or the bottom number > 110), the diagnosis is made regardless of symptoms or lab values. Women can often experience belly pain, visual changes, severe headaches, swelling, or have seizures, but some have no symptoms at all. Depending on how far along a mother is in her pregnancy, the treatment is usually delivery of the baby.
Why does preeclampsia happen?
Preeclampsia is the result of defective formation and implantation of the placenta. For reasons not completely clear, vascular remodeling of the maternal spiral arteries does not occur properly, which results in the placenta receiving an insufficient blood supply. This results in activation of the inflammatory factors and dysfunction of the blood vessels, leading to vasoconstriction (clamping down of the arteries). This increases pressure within the vasculature and results in systemic hypertension (high blood pressure). The vasoconstriction also results in decreased blood flow to different organs, resulting in symptoms such as headache, visual changes, and abdominal pain as well as organ failure, including kidney damage, liver damage, and seizures.
The risk factors for preeclampsia
The major risk factors for pre-eclampsia include genetic predisposition, acquired traditional risk factors for cardiovascular disease, and immunologic or rheumatic disease.
Prior pre-eclampsia, abruption, or stillbirth in another pregnancy
Chronic high blood pressure
Diabetes
Lupus, rheumatoid arthritis, and antiphospholipid syndrome
Chronic kidney disease
Overweight (BMI>25) or obese (BMI>30) prior to pregnancy
Age > 35 years
Twins or multiple births
Assisted reproductive technology like IVF
First pregnancy
First degree relative with pre-eclampsia
Of these risk factors, having had preeclampsia before is the greatest risk factor for having preeclampsia again, with recurrent pre-eclampsia occurring in 16-20% of women.
The long term risks of preeclampsia
Women with pregnancy-related high blood pressure issues are at risk for chronic high blood pressure, heart disease, stroke, heart failure, diabetes, metabolic syndrome, and kidney disease.
It’s not totally clear whether the physiologic demands of pregnancy unmask underlying cardiometabolic disease (pregnancy as a “stress test” theory) or if preeclampsia causes damage to the vasculature and/or triggers an inflammatory or autoimmune response. Research has demonstrated that years after an affected pregnancy, women have persistent markers of inflammation, coagulation, and vascular dysfunction. It’s very likely they all contribute, quite possibly in different ways for different women.
A woman’s risk particularly goes up with preeclampsia that is severe, early (before 34 weeks), and if it recurs. Perhaps most concerning is that women with preeclampsia have been found to have an increased risk of heart attacks and strokes as early as 3 to 10 years after the affected pregnancy. It also appears that even in women without traditional risk factors, the associated increased risk of heart disease remains.
What to do after preeclampsia?
Most importantly, know your risk and discuss your pregnancy history with your doctor!
The American College of Obstetrics and Gynecology recommends that women with a history of pregnancy complications and/or cardiovascular risk factors undergo cardiovascular risk screening within 3 months postpartum. Most women are not offered this or are lost to follow-up.
Women with pregnancy complications should have:
an aggressive cardiometabolic risk assessment, including checking closely for signs of insulin resistance or lipid disorders
close blood pressure follow-up. If blood pressure remains elevated beyond ~3 months postpartum, this is considered chronic hypertension and should be managed as such
With regards to long-term heart health, the American Heart Association and American College of Cardiology considers a history of preeclampsia or pregnancy-induced hypertension a risk-enhancing factor for the development of heart disease. However, it’s not formally included in the typical risk equation that is used to calculate the 10-year risk of cardiovascular disease, and patients and doctors alike are often unaware of the association. Pregnancy complications are independent risk factors for cardiovascular disease, and your doctor should be aware of this when assessing your heart health.
While there is very little data on interventions that may mitigate cardiovascular risk specifically in women with a history of preeclampsia or other pregnancy complications, the research we do have suggests that lifestyle changes are important.
Exercise, in particular, may be very important. One study found that women with normal blood pressure, but who had a history of preeclampsia, had improved autonomic function, endothelial function and plasma volume following an exercise program. Notably, however, they only improved these parameters to that of untrained, healthy controls
Maintaining a normal weight may also be very important for women with a history of preeclampsia. One study found that higher body mass index (BMI > 22.5 kg/m2 and higher) in particularly was associated with increased risk of chronic hypertension in women with a history of hypertensive disorders of pregnancy
Research is ongoing to help us learn more about what causes preeclampsia, how to prevent it, and what to do about it in the future. In the meantime, it should be viewed as just one of many pieces to the puzzle that determines your cardiovascular risk. When possible, optimizing all other risk factors as able, including nutrition and exercise, remain the foundation for future cardiovascular disease prevention!
