Nigeria has the highest number of people living with sickle cell disease (SCD) in the world, amounting to 2-3% of the population. SCD is a debilitating illness and in the past, very few people with the condition survived till adulthood. In the past 60 years, with improved care, more people have been surviving. Over 50% of females with SCD now achieve pregnancy due to this increased survival but they have a high incidence of complications during pregnancy including hypertensive disease called preeclampsia, growth restriction of their babies, severe illness that almost results in death (which we call near miss), and actual deaths of the women and their babies during pregnancy and delivery. There clinical course is also variable and although most women have complications, some women have fewer than others and a very small percentage actually have no problems during pregnancy and delivery.

My team and I have done a lot of work in this area, including a major doctoral thesis. During these studies, we found an abnormality in the ratio of certain hormones or chemicals in the body of these women, known as prostacyclin-thromboxane ratio. This same situation has been found in non-sickle pregnancies with preeclampsia and unexplained IUGR but we were the first to report it in sickle cell pregnancy+.

Aspirin was originally conceived as a painkiller but in a lower dose, it has been found to be very useful in many clinical conditions when taken daily e.g. for stroke and heart disease. Over the last 25-30 years, it has also been found useful in pregnancy – to prevent IUGR and preeclampsia due to its correction of the reversed prostacyclin thromboxane ratio,

Aspirin is safe in pregnancy and is recommended in many guidelines for this use – this here is the guideline of the National Institute for Health and Care Excellence in the UK for the Management of Hypertension in Pregnancy and aspirin is being advocated.

See the NICE guideline on antenatal care for advice on risk factors and symptoms of pre-eclampsia. [2010, amended 2019]

Anti-platelet Agents

1.1.2.
Advise pregnant women at high risk of pre-eclampsia to take 75-150 mg of aspirin daily from 12 weeks until birth of the baby. Women at high risk are those with any of the following:

• Hypertensive disease during a previous pregnancy
• Chronic kidney disease
• Auto immune disease such as systemic lupus erythematosus  or antiphospholipid syndrome
• Type 1 or Type 2 diabetes
• Chronic hypertension [2010, amended 2019]

1.1.3
Advise pregnant women with more than 1 moderate risk factor for pre-eclampsia to take 75-150 mg of aspirin daily from 12 weeks until birth of the baby. Factors indication moderate risk are:

• First Pregnancy
• Age 40 years or older
• Pregnancy interval of more than 10 years
• Body mass index (BMI) of 35kg/m or more at first visit
• Family history of pre-eclampsia
• Multi-fetal pregnancy [2010, amended 2019]

Severity and Variability of Sickle Cell Pregnancy

MOTHER

• crises, urinary and respiratory infectons, malaria
• Generally increased morbidity and mortality.

FETUS

• Prematurity
• Intra-uterine growth restriction
• Increased perinatal mortality

There is a great deal of variability in their clinical course. Also many near miss events in the mothers.

Expected Outcomes and Impact

Pertinent References

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