Sickle Cell Disorder and Pregnancy
Sickle cell disorder (SCD) is an inherited, genetic blood disorder that is passed down through families. Both parents need to carry the sickle gene for their baby to have sickle cell anemia (Hb SS).
If you have SCD and you’re trying to conceive or you’re pregnant, see your doctor as soon as you can. Your doctor will refer you to a specialist sickle cell care team at the hospital. They will monitor your symptoms, as you may have more episodes of pain during pregnancy and your anemia may become worse. Taking extra folic acid, eating a healthy diet and drinking plenty of fluids (non-alcoholic) can help maintain good health. The team will also monitor you and your baby throughout your pregnancy to keep you both as well as possible. With SCD, there is a higher risk of having complications such as miscarriage, pre-eclampsia, premature labor or your baby being too small for your stage of pregnancy. You may also need blood transfusions to help your baby grow well.
How Does Pregnancy Affect SCD?
Some women have no change in their SCD during pregnancy. However, sickle cell crises (painful events) may still occur in pregnancy and may be treated with medications that are safe to use during pregnancy. Pre existing kidney disease and congestive heart failure may worsen during pregnancy, even with proper treatment. The ability of the blood cells to carry oxygen is especially important in pregnancy. The anaemia may result in lower amounts of oxygen going to the fetus and cause slowed fetal growth. Due to the fact that the sickle cell disorder affects so many organs and body systems, women with SCD are more likely to have complications in pregnancy. Complications and increased risks for the mother may include but are not limited to the following:
- Infection, including urinary tract (especially kidney) and lungs.
- Heart enlargement and heart failure from anaemia
Complications and increased risks for the fetus may include, but are not limited to the following:
- Intrauterine growth restriction (poor Fetal Growth)
- Preterm birth (before 37 weeks of pregnancy)
- Low birth weight (less than 5.5 pounds)
- Stillbirth and newborn death
How is SCD managed during pregnancy?
Early and regular care is important for pregnant women with SCD. More frequent prenatal visits allow for close monitoring of the woman and of fetal well being. General pregnancy care includes a healthy diet, prenatal vitamins, folic acid supplements and preventing dehydration. Some women may benefit from blood transfusions to reduce the proportion of sickle cells in circulation. These may be done several times during the pregnancy to help increase the blood’s ability to carry oxygen.
Fetal testing may begin in the second trimester and include:
- Ultrasound scans (to measure fetal growth)
- Non stress test- measures fetal heart rate in response to fetal movement
- Biophysical profile – a test that combine an ultrasound scan with the non stress test
- Doppler flow studies – a type of ultrasound scan which uses sound waves to measure blood flow.
During labor, intravenous (IV) fluids are given to help prevent dehydration. Most women will receive extra oxygen through a mask during labor and a fetal heart rate monitor is often used to watch for changes in heart rate and signs of fetal distress. There are no special recommendations for the type of delivery for women with SCD and most can deliver vaginally, unless there are specific reasons requiring assisted or operative delivery.
It is important that a woman living with SCD and her family are counseled on limiting family size. A woman with SCD has a higher risk of problems occurring during pregnancy and delivery. The Progesterone-only contraceptive (e.g. mini pill), depo-provera, mirena (levornogesterel) and intra uterine device are safe. The combined pill can also be used as a second line therapy. Bilateral tube ligation is preferred for women with SCD who have completed their families. It is usually recommended that they do not have more than two children.
Although the age at puberty is higher than in Hb AA girls, there is no evidence of decrease in fertility in women with Hb SS or Hb SC.