High blood pressure (hypertension) can increase the risk of pregnancy complications for women and their babies.

High blood pressure during pregnancy can affect the growth of the placenta, which supplies nutrients and oxygen to the baby. This can lead to early delivery, low birth weight, placental separation (abruption), and other complications for the baby.

With the proper management of high blood pressure, though, pregnant people with this condition can minimize the risk of these complications. Your healthcare provider will also closely monitor your condition and pregnancy if you have high blood pressure.

Five things you should know about high blood pressure and pregnancy:

High blood pressure and fertility

Fertility issues linked to high blood pressure can affect both parents. Barring the condition itself, medications used to treat high blood pressure can affect fertility as well.

Females living with high blood pressure may have more trouble conceiving. One study revealed that the risk of pregnancy loss, or miscarriage, increased by 18% for every 10 mmHg increase in a person’s diastolic blood pressure.

Chronic high blood pressure before pregnancy is also linked to poor egg quality due to excessive estrogen production. If a poor-quality egg is fertilized, the embryo may not be able to implant in the uterus. Even if the embryo succeeds at implanting, it may not be able to develop properly. And may result in a miscarriage.

High Blood Pressure and Heredity

An estimated 30% to 50% of cases of hypertension are linked to genetics. Make sure you talk to your doctor about your family history and any health risks you may have if you are trying to become pregnant, especially if you are having trouble conceiving.

High Blood Pressure and Gestation

High blood pressure may increase your risk of complications during pregnancy. You can have hypertension in pregnancy either as a continuance of a chronic problem that you had before you were pregnant or as a new problem that develops during your pregnancy, which is called gestational hypertension or preeclampsia.

Pregnancy and Recommended Blood Pressure Range

Some increases in blood pressure are expected because your blood volume will rise and the pregnancy will be more demanding on your cardiovascular system. Normal blood pressure is a systolic blood pressure less than 120 mmHg and a diastolic blood pressure less than 80 mmHg.

The American College of Obstetricians and Gynecologists (ACOG) urges treatment for high blood pressure if your systolic blood pressure is 160 mmHg or higher or if you have a diastolic blood pressure of 110 mmHg or higher. Sometimes treatment is recommended at lower levels in women with other risk factors.

High Blood Pressure and Postpartum

Even after delivery, your healthcare team will continue to monitor your blood pressure closely. Your blood volume and fluid levels shift dramatically in the postpartum period. This can cause significant fluctuations in blood pressure. Eclampsia or preeclampsia can develop up to six weeks after delivery.