Pregnancy-Induced Hypertension Home A-Z Health Information Health Library A-Z Pregnancy-Induced Hypertension Overview Approximately 10‒12% women experience increased blood pressure during pregnancy (hypertensive disorders of pregnancy), and of these, ~6% are diagnosed with pregnancy-induced hypertension (PIH), also known as gestational or transient hypertension, a condition characterised by hypertension without proteinuria (protein in urine). According to the guidelines proposed by the American College of Obstetricians and Gynaecologists, PIH is defined as the presence of blood pressure greater than or equal to 140/90 mmHg at two separate instances (measured at an interval of at least 4 hours) after 20 weeks of pregnancy (when the previous blood pressure was normal). Though PIH generally subsides by the 6th week after delivery, it is a concerning condition as it can affect placenta development and function, meaning that the foetus may not get adequate nutrients, and both the mother and child are at high risk of developing complications (before labour, during labour, and after delivery). If left unmanaged, PIH can progress to serious conditions like preeclampsia, which can cause organ damage, seizures, and complications for the baby. Causes Although the exact cause of PIH has not yet been identified, certain risk factors for this condition have been identified:Age: Women over 35 years of age are at moderate risk of developing PIH.First pregnancy: PIH is more common in first-time mothers.Multiple pregnancies: Carrying twins or triplets increases your chances of developing PIH.Pregnancy-related conditions: Having or PIH or preeclampsia during previous pregnancies can increase the risk of developing PIH.Obesity: Being overweight before pregnancy can also contribute to PIH.Pre-existing illness: PIH risk is higher in case of pre-existing illness, such as chronic hypertension, kidney disease, diabetes, or lupus.Family history: A history of PIH or preeclampsia in the family is also a key risk factor. Symptoms High blood pressure (>140/90 mmHg).Severe headaches that do not go away.Blurred vision or seeing spots.Pain under the ribs (upper abdomen).Sudden swelling of limbs (hands/feet) or face.Fluid retention and subsequently, rapid weight gain.Reduced urine output.Thrombocytopenia (low platelet count). Diagnosis Hypertensive disorders of pregnancy are diagnosed based on consistently high blood pressure measurements (above 140/90 mmHg) during blood pressure monitoring. Additionally, as weight gain during pregnancy can increase the risk of these hypertensive disorders, frequent weight measurements are used to monitor them However, the diagnosis of PIH is more of an elimination analysis, i.e., the patient does not develop preeclampsia (no protein in urine) and the blood pressure values return to normal by week 6 after delivery. In other words, a diagnosis of PIH is made after ruling out other more hypertensive disorders of pregnancy, such as preeclampsia, chronic hypertension, and the superimposition of the two. One or more of the following routine diagnostic techniques are used to diagnose PIH:Urine tests: Urine samples are checked for the presence of protein to rule out preeclampsia.Oedema assessment: Swelling in both legs (bilateral leg oedema) is indicative of PID.Liver and kidney function tests: These tests are used to rule out preeclampsia.Blood clotting tests: These tests are used to rule out preeclampsia.If a diagnosis of PID is made, physicians also perform routine tests to monitor foetal health; these include:Ultrasound: This test helps monitor the baby’s development and check for complications.Non-stress test: This test is used to observe the baby’s heart rate and ensure that they are doing well in the womb.Foetal movement counting: This test involves keeping track of the number or frequency of foetal kicks and movements, a change in which indicates foetal stress.Biophysical profile: This test—usually performed after the 28th week of pregnancy—involves combining the nonstress test with ultrasound to observe the foetus.Doppler flow study: This type of ultrasound is used to measure the flow of the baby’s blood through a blood vessel. Treatment PIH treatment is aimed at managing your blood pressure and preventing it from progressing into more dangerous conditions like preeclampsia. Treatment depends on the severity of your condition and how far along you are in your pregnancy.Lifestyle changes: In mild cases, your doctor may recommend more rest, reducing salt intake, and frequent monitoring.Medications: If blood pressure is too high, your doctor may prescribe antihypertensive medications (medications to control the blood pressure). However, if PIH progresses to preeclampsia, magnesium sulphate may be used to prevent seizures.Hospitalisation: In severe cases, your doctor may recommend a hospital stay for close observation and management.Early delivery: If PIH puts you or your baby at risk, early delivery might be the best option, sometimes through labour induction or a caesarean section. Prevention Though PIH cannot be prevented, the below steps help in reducing PIH risk and ensuring a healthier pregnancy:Maintaining a healthy weight: Patients are advised to attain a healthy weight before pregnancy and follow the doctor’s advice for weight gain during pregnancy.Consuming a balanced diet: Diet comprising fruits, vegetables, proteins, grains, and diary with less salt helps to control hypertension.Staying active: Light to moderate exercise can help manage weight and maintain healthy blood pressure levels. Attending prenatal appointments: Regular check-ups are essential for catching PIH early.Monitoring blood pressure at home: If you are at risk, your doctor may advise you to keep an eye on your blood pressure between appointments.