Hypertension during pregnancy is still a major cause of death and morbidity of mothers and infants in the world. The incidence rate ranges from 1-8 percent. Hypertension during pregnancy is divided into four types: Preeclampsia-eclampsia, chronic hypertension, chronic hypertension with preeclampsia, and gestational hypertension.
Research on the impact of preeclampsia-eclampsia on mothers and fetuses has been widely carried out. However, chronic hypertension during pregnancy is still a topic that is rarely discussed. So, we conducted a study on the effects of chronic hypertension during pregnancy, related to the severity of hypertension.
Chronic hypertension can be defined as an increase of blood pressure before pregnancy (or gestational age <20 weeks), or if only happens during pregnancy, will persist after 12 weeks postpartum. Chronic hypertension can be divided into two groups according to The Seventh Joint National Committee (JNC 7): stage 1 (systolic blood pressure 140-159, diastolic: 90-99) and stage 2 (blood pressure> 160/110 mmHg).
In other words, stage 2 is more severe clinically than stage 1. Chronic hypertension during pregnancy is diagnosed by looking at the history of blood pressure testing and drug use before pregnancy. The two groups were compared to pregnancy outcomes both in terms of the mother and fetus. This research was conducted at Dr. Soetomo, Surabaya from January 2013 to December 2017.
From 6,950 patients who gave birth at Dr. Soetomo in this period, we got 352 pregnant women with chronic hypertension. From what we know, this is the first publication about pregnancy with chronic hypertension complication in Indonesia.
The incidence of chronic hypertension in this study was around 5 percent but did not reflect the incidence in the general population, because the location of the study was carried out at Dr. Soetomo, which is a tertiary referral center, which only accepts high-risk cases.
Year by year, we get an increasing number of cases with chronic hypertension during pregnancy. It may be due to the increasing number of risk factors for hypertension in pregnant women such as obesity, maternal age> 35 years, hormonal therapy, diabetes, autoimmune diseases, and kidney.
Our research showed that stage 2 group had worse pregnancy outcomes for both mother and fetus than stage 1. The risk of maternal death increased 7.2-fold in stage 2. This result was in accordance with a variety of literature which states that high blood pressure will increase the risk of stroke and mortality in mother.
We got eight maternal deaths in this study and 6 of them in the stage 2 group. The main problem in cases of maternal death was the delay in referral to the hospital so that patients come in a state of severe complications. Moreover, there is also low compliance of patients in getting checked out during pregnancy to a health facility, so the diagnosis is often late.
Pregnancy complications greatly increased in stage 2 hypertension, including the incidence of preeclampsia, eclampsia, placental bleeding, treatment in the Intensive Care Unit (ICU), and the use of ventilators. What’s interesting about our findings is that the rate of preeclampsia complication is very high in both groups.
It was consistent with various systematic studies which stated that chronic hypertension increases the risk of preeclampsia. Other factors in our study that increase the risk of preeclampsia include the high number of patients aged> 35 years, obesity, and the presence of other comorbidities. In this study 58-60 percent of patients gave birth by cesarean section, the main indications included the presence of fetal distress in the uterus, placenta previa, history of recurrent cesarean delivery, abnormal fetal position and multiple pregnancies. The stage 2 group also requires far more anti-hypertensive drug therapy than stage 1. Patients in stage 2 require a combination of nifedipine and methyldopa drugs to control blood pressure, whereas in stage 1 only require one drug or none at all.
High blood pressure is also associated with worse fetal outcomes, including low birth weight, low Apgar score, and complications in pregnancy (fetal distress, stunted growth, and fetal death). The number of babies with low birth weight in our study was quite high.
The high-risk was from a high rate of preterm birth, either spontaneously or medically indicated because of complications in the mother and fetus. It is in line with many other studies which stated that high maternal blood pressure is associated with an increased risk of stunted fetal growth, preterm birth, and respiratory problems for newborns, associated with impaired blood flow in the fetus and placenta.
Chronic hypertension during pregnancy in Indonesia is still a major risk factor for poor pregnancy outcomes both mother and fetus, and especially stage 2 is associated with an increased risk of maternal death, maternal complications, and poor fetal outcomes. Pregnant patients with stage 2 require early diagnosis and referral to tertiary health facilities so that treatment can be carried out completely with a multidisciplinary approach. (*)
Author: dr. Muhammad Ilham Aldika Akbar, SpOG(K)
Details of this research available at:
Muhammad Ilham Aldika Akbar, Muhammad Arief Adibrata, Aditiawarman, Rozi Aditya Aryananda, Muhammad Dikman Angsar, Gustaaf Dekker, 2019. Maternal and perinatal
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