How to prevent hypertension in pregnancy


Mrs Adams (not real name) was three months pregnant when she was diagnosed with hypertension in pregnancy but she was able to manage it till she delivered the baby safely. The mother of one said her pregnancy wasn’t an easy one with the ailment but added that adhering to her doctor’s prescription and advice helped her.

Experts say hypertension in pregnancy is the most common medical problem seen in pregnancy and complicate five to seven percent of all pregnancies. They said it constitutes a major threat to maternal life during pregnancy, labour and immediate post-partum period. It is also ranked amongst the four most prominent contributors to maternal deaths.

Dr. Victor Ohenhen, a Consultant Gynaecologist and Obstetrician, described hypertension as a systolic blood pressure (SBP) of 140mmHg and above a diastolic blood pressure of 90mmHg and above.

He said early presentation, diagnosis and adequate ante-natal care are very helpful to stop the disorder from further progression in order to save the mother and baby.

According to him, hypertension in pregnancy is in two forms – gestational hypertension and pre-eclampsia. He said: “Gestational hypertension is the development of hypertension in the latter half of pregnancy or during labour without other evidence of pre-eclampsia or chronic hypertensive vascular disease which usually regressed with delivery of the baby (at most 14th day).

“In these patients, there is hypertension but no proteinuria. It may re-occur and they are predisposed to essential hypertension later in life. The outcome of pregnancy is usually good. “Pre-eclampsia is the development of hypertension accompanied by proteinuria with or without oedema, occurring in the second half of pregnancy in a previous normotensive non-proteinuric woman. It is essentially a disease of primigravida and it complicates about 2 to 3 percent  of pregnancies.”

The medical expert said the prevalence of hypertensive disorders in pregnancy, gestation hypertension and pre-eclampsia are 5.2 to 8.2 percent, 1.8 to 4.4 percent and 0.2 to 9.2 percent respectively.

Dr Ohenhen said  some of the  factors that may increase the risk, are nulliparity (a woman’s state or condition of never having been pregnant or given birth to a child or young children), very obese women, family history of pre-eclampsia, pre-existing hypertension, renal disease, pre-existing vascular disease, and  enlarged placenta as in diabetes mellitus.

Others include multiple gestation and extremes of age (more common in 20 years and 35 years as well as change of partner) among others. He said the disorder may  have no symptoms especially in mild cases but there is increase in blood pressure, proteinuria, fluid retention causing oedema (especially non-dependent oedema), brisk reflexes.

According to him, there are cerebral manifestation in severe cases which  include, headaches, dizziness, tinnitus, drowsiness, change in respiration, hyperreflexia, tachycardia and fever.

“The patient may also have visual changes like  blurred vision, diplopia, gastrointestinal symptoms: epigastric pains, nausea and vomiting and signs of help syndrome,” he said. Dr Ohenhen said the  control of hypertension in pregnancy is to stop further progression of the disease and prevent  fits and save the mother followed by delivery of a live, mature baby.

He explained that the ultimate aim of management is safety of the mother first and that in severe cases, the fetus is sacrificed in the interest of the mother. He said the decision between expectant management and immediate delivery depends on the severity of the disease process, maternal condition and gestational age, adding that if a decision is taken for immediate delivery, mode of delivery will depend on the condition of the fetus and cervical effacement.

“For mild cases, bed rest is good therapy for fetal survival because it reduces blood pressure, improves utero-placental flow and aids fetal growth such that the fetus is mature enough to decrease prolonged neonatal intensive care admission. For moderate to severe cases, anti-hypertensive agents are needed and also sedatives. A wide variety of anti-hypertensives are used,” he said.

Dr. Ohenhen, who is also the Head, Department of Gynaecology and Obstetrics, Central Hospital, Benin, said adequate ante-natal care would help reduce late presentation and maternal mortality associated with hypertension in pregnancy. Ante-natal care is the hallmark in achieving better prognosis with hypertension and its complications, he said.