A 37-year-old woman presents for review. She is 26 weeks pregnant and has had no problems with her pregnancy to date. Blood pressure is 144/92 mmHg, a rise from her booking reading of 110/80 mmHg. Urine dipstick reveals the following:
Protein negative
Leucocytes negative
Blood negative
What is the most appropriate description of her condition?
Moderate pre-eclampsia
Mild pre-eclampsia
Gestational hypertension
Normal physiological change in blood pressure
Pre-existing hypertension
Hypertension in pregnancy
NICE published guidance in 2010 on the management of hypertension in pregnancy. They also made recommendations on reducing the risk of hypertensive disorders developing in the first place. Women who are at high risk of developing pre-eclampsia should take aspirin 75mg od from 12 weeks until the birth of the baby. High risk groups include:
hypertensive disease during previous pregnancies
chronic kidney disease
autoimmune disorders such as SLE or antiphospholipid syndrome
type 1 or 2 diabetes mellitus
The classification of hypertension in pregnancy is complicated and varies. Remember, in normal pregnancy:
blood pressure usually falls in the first trimester (particularly the diastolic), and continues to fall until 20-24 weeks
after this time the blood pressure usually increases to pre-pregnancy levels by term
Hypertension in pregnancy in usually defined as:
systolic > 140 mmHg or diastolic > 90 mmHg
or an increase above booking readings of > 30 mmHg systolic or > 15 mmHg diastolic
After establishing that the patient is hypertensive they should be categorised into one of the following groups
Pre-existing hypertension Pregnancy-induced hypertension
(PIH, also known as gestational hypertension) Pre-eclampsia
A history of hypertension before pregnancy or an elevated blood pressure > 140/90 mmHg before 20 weeks gestation
No proteinuria, no oedema
Occurs in 3-5% of pregnancies and is more common in older women Hypertension (as defined above) occurring in the second half of pregnancy (i.e. after 20 weeks)
No proteinuria, no oedema
Occurs in around 5-7% of pregnancies
Resolves following birth (typically after one month). Women with PIH are at increased risk of future pre-eclampsia or hypertension later in life Pregnancy-induced hypertension in association with proteinuria (> 0.3g / 24 hours)
Oedema may occur but is now less commonly used as a criteria
Occurs in around 5% of pregnancies