High blood pressure, or hypertension, is a chronic health condition that can lead to many medical complications, but having high blood pressure does not directly make it more difficult to become pregnant. Hypertension itself does not affect a woman’s supply of eggs, her ability to ovulate or the health of her eggs and embryos. Although there is some suggestion in the scientific literature that high blood pressure might affect the lining of the uterus, which could interfere with an embryo’s healthy implantation, this issue is mostly theoretical. A diagnosis of high blood pressure, however, is still significant to a woman who wants to conceive, for a number of reasons.
Most women of reproductive age who have hypertension also have one or more associated conditions that do have a negative effect on fertility. Common examples include obesity, smoking and being older than 40. Each of these circumstances is strongly associated with an increased risk for hypertension as well as decreased fertility. Polycystic ovarian syndrome, or PCOS, is another condition frequently related to obesity and infertility, as well as high blood pressure.
Many blood pressure medications are not safe to use during pregnancy. Before becoming pregnant, women who take anti-hypertensives may need to talk with their doctor about switching to a blood pressure medication that is safely compatible with pregnancy. Medicines with a pregnancy category of A or B are preferable; category C medications are sometimes acceptable, but must be discussed with a doctor.
Once pregnant, women with chronic high blood pressure are at significantly higher risk for pregnancy complications, such as miscarriage, pre-eclampsia, poor fetal growth and premature placental separation. A pre-conception consultation with a high-risk obstetrician to discuss possible risks and optimise medications and management before becoming pregnant can help decrease the chance of potential complications.