Pregnancy and Your Heart

In about 1 in 100 pregnancies the mother has a preexisting heart condition often resulting from rheumatic fever or a congenital heart malformation. It is crucial that the obstetrician be informed of any preexisting heart problems. Unless heart damage is severe, quality care usually leads to a healthy outcome for mother and baby. However, even those who feel well and are usually able to tolerate exertion may need additional monitoring and restrictions of activity during pregnancy. The likelihood of favorable outcome for the mother and baby in pregnancies complicated by heart disease is primarily affected by the extent of disease and the likelihood of other complications that could further compromise the heart's function.

Women who have heart disease amenable to surgical correction who want to get pregnant should plan to have the operation before attempting to conceive. The treatment of heart disease in pregnancy varies, depending on the type and severity of disease. Evaluation by a cardiologist before pregnancy and several times during pregnancy is often recommended. Prenatal care will be aimed at avoiding any complications that increase the heart's work load. It is especially important to avoid excessive weight gain minimize salt intake (to avoid fluid retention), and get adequate iron from food and supplements to avoid anemia. Plenty of rest, along with avoidance of all unnecessary exertion, is important even among those who have not had to limit their activity level before pregnancy. The support and cooperation of family members and employers is especially important in order to minimize physical and emotional stress.

Antibiotics may be prescribed as a preventive measure at several points during pregnancy if dental work is needed during labor and delivery, or at the first sign of infection. Contact with people with respiratory infections should be avoided and even a mild cold should be reported to the physician immediately. Some doctors also recommend immunization against pneumonia and influenza.

In spite of the physical effort required in labor and delivery, vaginal delivery is safer and less likely to be complicated than cesarean section. If labor is prolonged, continuous epidural anesthesia and other analgesics are often used to relieve pain, and forceps may be used to assist delivery during the bearing down stage. Proper positioning and use of oxygen can also ease the heart's workload during labor. Postpartum hemorrhage, infection, and thromboembolism occur much more frequently in women with heart disease, even when there has been no indication of heart failure during pregnancy, labor, or delivery. Therefore, the mother will be advised to remain in the hospital for close monitoring after delivery.

In general, heart disease in pregnancy poses a greater risk to the mother than to the fetus. Important exceptions are types of heart disease that interfere of with the transport of oxygen to the fetus which can slow the baby's growth and in severe cases, can lead to miscarriage and premature delivery, and those that must be treated with beta-blocking drugs that cross the placenta.

Chronic Hypertension:

Uncontrolled hypertension (high blood pressure) can be lethal during pregnancy, which is why every pregnant woman's blood pressure should be checked regularly throughout the 9 months. Those with chronic hypertension need to be particularly careful about having blood pressure checked throughout pregnancy and ideally should have baseline prepregnancy levels established for comparison before conception. Kidney function tests are sometimes done throughout gestation to ascertain whether maternal kidney function is deteriorating.

Consistently high blood pressure can reduce the amount of blood flow to the placenta, limiting the supply of oxygen and nutrients reaching the fetus. Fetal death or intrauterine growth retardation are the most serious consequences. To confirm that fetal growth is proceeding normally, a sonogram is usually done before 24 weeks and again at about 34 weeks. If growth is severely compromised, the fetus may be delivered prematurely and cared for in a neonatal intensive care unit. If growth is normal and pregnancy proceeds without any additional problems, a normal vaginal delivery can be expected.

Blood pressure tends to drop during the first half of pregnancy. Mild hypertension that has been successfully controlled with diet and exercise before pregnancy can probably be sustained without antihypertensive medications. Even mothers who have been on medication for years do surprisingly well. During pregnancy, physicians will select antihypertensive medications that do not interfere with blood flow to the uterus. Because it causes a reduction in blood volume, diuretic therapy is not usually started or continued during pregnancy.

Taking a 2-hour rest each day while reclining on the left side can increase blood flow to the kidney and placenta by 15 to 20 percent. Circulation to the fetus can also be improved by refraining from smoking and getting plenty of rest. When hypertension occurs for the first time after 20 weeks of pregnancy, it is labeled gestational hypertension. Pressure usually returns to normal after the pregnancy but gestational hypertension usually puts you at risk of developing hypertension later in life.

Preeclampsia:

The cause of preeclampsia also called toxemia of pregnancy is not known. It occurs only in pregnancy, specifically after week 20. It is more likely to occur in first pregnancies or where there is a history of high blood pressure or vascular disease. Age (under 20 or over 40 years), the presence of diabetes or kidney disease, a family history of high blood pressure, and a mother or sisters who had preeclampsia are also risk factors. Fortunately, a woman who develops it once is unlikely to develop it again in a subsequent pregnancy. A well-balanced diet and good prenatal care provide some insurance against preeclampsia, but it occurs nevertheless in about 5 percent of all pregnancies.

The classic symptoms of preeclampsia are high blood pressure, swelling of the face and hands, and protein in the Urine. In severe cases, there is significant reduction in urine output. These symptms may develop over the course of a fewlays or may appear suddenly in a 24-hour Period. They may appear together, or separately, and in any order. Rarely, vomiting, pain in the upper abdomen, and blurred vision accompany the other symptoms. A physician should be consulted immediately if any of these symptoms occur.

Each prenatal visit includes procedures to screen for preeclampsia: blood pressure check, urinalysis (to test for protein), weight (to detect hidden fluid accumulation), and physical exam to detect swelling or fluid accumulation. If undetected and untreated, preeclampsia can develop into eclampsia, a dangerous condition that puts both mother and baby at risk.

Early treatment usually forestalls this serious development. If the condition is relatively mild, bed rest at home is usually recommended. Lying in bed, on the left side, helps to increase blood flow through the kidneys, increases urination, and so relieves fluid retention. In more severe cases, hospitalization will be needed. If the condition is serious and develops near the time of delivery, intravenous medication will be given to lower the blood pressure and prompt delivery will be considered.

A major complication of preeclampsia is abruptio placentae, or placental separation. Therefore the baby will usually be delivered as soon as possible after the mother's condition has been stabilized. If vaginal delivery seems possible, labor will be induced; if not, a cesarian section  is done.

Eclampsia:

If preeclampsia progresses without treatment, eclampsia may develop, although sometimes this serious condition arises rapidly and without warning. Blood pressure soars and there may be convulsions. Coma, severe headache, confusion, and visual disturbances may precede or follow other signs. Eclampsia is life threatening and immediate treatment is required to save both mother and child. As in severe preeclampsia, medication are given to lower the blood pressure and prevent (or treat) convulsions. Delivery will often be accomplished as soon as possible. Preeclampsia progresses to eclampsia in 1 case in 200, but this rarely happens with good prenatal care.