Raised BP affects roughly one pregnancy in ten. Pre-eclampsia complicates about 3–5% of pregnancies worldwide, and reported rates in India are higher. It is one of the main causes of serious illness in mothers and babies. Much of that harm can be reduced when the condition is expected, picked up early and managed to a plan.
Some women already have high BP before they conceive (chronic hypertension). Others develop it for the first time after 20 weeks (gestational hypertension). Pre-eclampsia is different from both. It involves the placenta and can affect other organs - the kidneys, liver, blood clotting, brain and the baby's growth. It can also move from mild to severe within a few days.
Divine Women's Hospital is NABH-certified, and its labour ward, operating theatre and neonatal support run 24×7.
High BP in Pregnancy: The Four Kinds I See
Each kind carries a different level of risk and needs a different amount of monitoring. I diagnose high BP when a reading of 140/90 mmHg or more is confirmed on a repeat measurement after you have rested.
| Kind | What it means | How I manage it |
|---|---|---|
| Chronic hypertension | High BP before pregnancy, or found before 20 weeks | Tablets suitable for pregnancy, aspirin and growth scans; about 1 in 4 women go on to develop pre-eclampsia |
| Gestational hypertension | New high BP after 20 weeks, with no protein in the urine and no organ signs | Checks once to twice a week; about 1 in 4 progress to pre-eclampsia |
| Pre-eclampsia | High BP after 20 weeks with protein in the urine or signs that other organs are involved | Blood tests, growth and Doppler scans, often admission, and a planned delivery |
| Severe pre-eclampsia, HELLP, eclampsia | Severe-range BP, low platelets, liver involvement or seizures | Hospital care, magnesium sulphate, urgent BP control, and delivery once the mother is stable |
Pre-eclampsia can be diagnosed even without protein in the urine, if blood tests, symptoms or the baby's growth show that organs are affected.
What is high blood pressure in pregnancy called?
When BP rises for the first time after 20 weeks without other problems, the medical name is gestational hypertension, which many reports and older textbooks call pregnancy-induced hypertension (PIH). If the raised BP comes with protein in the urine or signs that organs are under strain, it is called pre-eclampsia. High BP that was present before pregnancy, or is found before 20 weeks, is chronic hypertension. The name matters because it decides how often I see you and which tests I order.
Pre-eclampsia Causes and Who Is More Likely to Get It
The process starts in early pregnancy, when the blood vessels supplying the placenta do not remodel fully. A placenta under strain then releases substances, one of which is called sFlt-1, that damage the lining of the mother's blood vessels. The result is a rise in BP and leakage of protein through the kidneys. Because this begins so early, the risk can be estimated in the first trimester - and partly changed.
Higher-risk factors
- pre-eclampsia or HELLP in an earlier pregnancy
- chronic hypertension
- chronic kidney disease
- type 1 or type 2 diabetes
- lupus or antiphospholipid syndrome
Moderate-risk factors
- a first pregnancy
- age 40 or above
- more than 10 years since the last pregnancy
- a BMI of 35 or more at booking
- pre-eclampsia in your mother or sister
- twins or more
Pregnancy after IVF, particularly with donor eggs, also adds to the risk. If you have one higher-risk factor, or two moderate ones, I advise aspirin to help prevent it.
The 11–14 Week Risk Check and the Prevention I Offer
At your NT scan I bring together your history, your mean arterial pressure, a Doppler of the uterine arteries and, where it is available, a blood test called PlGF. These are combined using the Fetal Medicine Foundation algorithm. This picks up a larger share of women at risk than history alone.
Aspirin. For women at raised risk, I recommend aspirin 150 mg taken at night, starting between 12 and 16 weeks and continuing to about 36 weeks. In the large ASPRE trial this cut preterm pre-eclampsia by more than half. Aspirin started after 16 weeks works less well - so if you have risk factors, please book in the first trimester.
Calcium. A typical Indian diet, especially one with little milk or curd, may not provide enough calcium. For women whose intake is low, WHO advises 1.5–2 g of elemental calcium a day. Take calcium and iron tablets at different times of day, because each reduces how well the other is absorbed.
Pre-eclampsia Symptoms to Watch For
Many women feel completely well until pre-eclampsia has taken hold. That is why I check your BP and urine at every visit, and often suggest a BP machine at home. Swelling of the ankles on its own is common in normal pregnancy and is not a reliable sign.
Tell us promptly if you have:
- a headache that does not go away with paracetamol and rest
- blurred vision, flashing lights or spots in front of the eyes
- pain under the right ribs or in the upper abdomen - sometimes mistaken for acidity
- new nausea or vomiting in the second half of pregnancy
- swelling that appears suddenly in the face, the hands or around the eyes
- breathlessness, passing less urine, or the baby moving less
Pre-eclampsia Test: Checks I Arrange Once Your BP Is Raised
How closely I monitor depends on how severe things are:
- BP checks once or twice a week - more often if you are in hospital.
- urine protein:creatinine ratio
- blood tests: haemoglobin, platelets, liver enzymes, creatinine and uric acid
- growth scans every two weeks, umbilical artery Doppler, and CTG where needed
- the sFlt-1/PlGF ratio, where available, between 20 and 37 weeks
A ratio of 38 or below makes pre-eclampsia within the following week very unlikely, so many women can be looked after at home rather than admitted.
High BP in Pregnancy: Medicine and the Tablets I Use
I aim for a BP of around 135/85 mmHg. Tighter control of this kind has not been shown to harm the baby, and it lowers the chance of severe hypertension. Please do not stop your tablets because one reading is normal - the normal reading is usually the tablets working.
| Medicine | How it is taken | Points to know |
|---|---|---|
| Labetalol | Often my first choice; 2–4 times a day | Avoided in asthma; can cause tiredness or a tingling scalp |
| Nifedipine (slow-release) | Once or twice a day; first choice if you have asthma | Headache and flushing in the early days are common and settle |
| Methyldopa | Long-established; 2–3 times a day | Can cause drowsiness and low mood; usually changed after delivery |
| ACE inhibitors and ARBs (enalapril, telmisartan, losartan) | Not used after the first weeks of pregnancy | Switch when you plan a pregnancy or as soon as it is confirmed; enalapril can be used while breastfeeding |
High Blood Pressure in Pregnancy: Effects on Baby and Placenta
High blood pressure in pregnancy affects the baby mainly through the placenta. When the vessels feeding the placenta are narrowed, less oxygen and nourishment get through, and growth can slow. On the scan the head often keeps pace while the abdomen falls behind. The amniotic fluid may also reduce, because a baby under strain passes less urine. Pre-eclampsia raises the chance of placental abruption too, where the placenta separates before birth and causes pain and bleeding; that is an emergency for both mother and baby.
The most common effect, though, is an earlier birth. Many babies of mothers with pre-eclampsia are delivered before term because carrying on has become riskier than delivery, and those babies may need time in the neonatal unit. This is why my monitoring always has two halves: your BP and blood results, and the baby's growth, fluid and umbilical artery Doppler. If the baby measures small, I follow the plan set out on my fetal growth restriction page. Well-controlled chronic hypertension without pre-eclampsia usually affects the baby far less.
When Pre-eclampsia Becomes Severe: HELLP and Eclampsia
BP in the severe range - 160/110 mmHg or more - needs treatment within the hour to protect against a stroke. This is usually nifedipine by mouth or labetalol into a vein.
Women with severe features are given magnesium sulphate. It greatly lowers the chance of a seizure, and if the baby is likely to be born before 32 weeks it also helps protect the baby's brain.
HELLP - breakdown of red cells, raised liver enzymes and low platelets - can develop even when the BP is only moderately raised. Other complications include placental abruption, fluid on the lungs (pulmonary oedema) and kidney injury. All of these are managed in hospital, with blood, theatre and neonatal care ready.
Deciding When Your Baby Should Be Born
Pre-eclampsia settles only once the placenta is delivered. Every timing decision weighs the mother's safety against how mature the baby is. If birth is likely before 34–35 weeks, I give steroid injections first to help the baby's lungs.
| Situation | Usual plan for delivery |
|---|---|
| Chronic or gestational hypertension, well controlled | Discussed at 37–39 weeks |
| Pre-eclampsia without severe features | Usually advised at about 37 weeks |
| Pre-eclampsia at 34–37 weeks | Decided individually; often delivery if it is getting worse |
| Severe features before 34 weeks | Stabilise and give steroids; deliver if the mother or baby becomes unstable |
| HELLP, eclampsia, abruption or BP that cannot be controlled | Delivery once the mother is stabilised, whatever the gestation |
For many women, induction of labour aiming for a vaginal birth is a good option. A caesarean is chosen when delivery is urgent or there are other obstetric reasons.
Pre-eclampsia Treatment After Birth, and Your Heart in the Long Run
BP often reaches its highest 3–6 days after delivery, so home checks continue. I reduce your medicines gradually over the following weeks, and most women are off tablets by 6–12 weeks. If your BP stays high, I arrange a review with a physician.
Pre-eclampsia is a lifelong signal. Women who have had it carry roughly four times the chance of chronic hypertension, and about double the risk of heart disease and stroke. A yearly BP check, a healthy weight, regular exercise, less salt, and sugar and cholesterol tests from time to time all help.
For your next pregnancy, we start from the first visit: aspirin from 12 weeks, calcium, baseline blood tests and closer growth scans.
High BP in Pregnancy Treatment: My Five-Stage Plan
- Risk check in the first trimesteryour history, BP and the 11–14 week scan tell us whether you need aspirin, calcium and closer monitoring.
- A BP plan written for youtarget readings, a medicine plan suited to pregnancy, and written limits for when to call or come in.
- Surveillance on a scheduleurine, blood tests, growth scans and Doppler arranged by severity, with ratios such as sFlt-1/PlGF where they help.
- A prepared, well-timed deliverysteroids, magnesium sulphate, labour or caesarean, and neonatal support arranged at Divine Women's Hospital.
- Follow-up after the birthBP checks in the first two weeks, reducing medicines, and a long-term plan for heart health.
Reasons to See Me About Blood Pressure in Pregnancy
- A BP of 140/90 mmHg or higher, at home or in a clinic.
- Pre-eclampsia, HELLP or eclampsia in an earlier pregnancy.
- Chronic hypertension, kidney disease, diabetes, lupus or APLA.
- A first pregnancy at 40 or over, an IVF pregnancy, or twins.
- Taking enalapril, telmisartan or losartan and planning a pregnancy.
- A BP review needed after a pregnancy that was complicated by high BP.
Pre-eclampsia Danger Signs: Come In the Same Day
- A home BP reading of 160/110 mmHg or higher.
- A severe headache that will not settle, or blurred vision and flashing lights.
- Pain in the upper right abdomen or under the ribs, with or without vomiting.
- A seizure, confusion or extreme drowsiness.
- Breathlessness or chest pain - including in the first week after delivery.
- The baby moving less, or differently.
With any of these, skip the OPD queue. Divine Women's Hospital keeps its labour room and emergency desk staffed day and night, 24×7. If you can, telephone while someone drives you in, and bring your home BP machine and readings.
What People Often Get Wrong About BP in Pregnancy
Belief: Swollen feet mean pre-eclampsia.
Ankle swelling is common in pregnancy. What concerns me is sudden swelling of the face or hands, high BP, or protein in the urine.
Belief: BP tablets will harm the baby, so it is better to manage without them.
Labetalol, nifedipine and methyldopa have a long record of use in pregnancy. Uncontrolled BP is far more dangerous for mother and baby.
Belief: Cutting out salt will prevent pre-eclampsia.
Severe salt restriction does not prevent it. Early aspirin for women at risk, enough calcium and regular monitoring are what make the difference.
Belief: Once the baby is born, the BP problem is over.
BP often peaks after delivery, and pre-eclampsia raises lifelong risk, so follow-up continues.
Questions Patients Often Ask Me About Pre-eclampsia
What BP reading is normal in pregnancy?
In healthy pregnant women BP often runs at about 100–120 systolic and 60–80 diastolic, with a dip in the middle trimester. A reading of 140/90 mmHg or more after rest needs to be reviewed.
What are the early symptoms of pre-eclampsia?
Often there are none, which is why routine checks matter. Warning symptoms include a headache that persists, changes in vision, pain under the right ribs, new vomiting, and sudden swelling of the face or hands.
Why is aspirin prescribed in pregnancy, and does it affect the baby?
Low-dose aspirin improves blood flow to the placenta. Taken as 150 mg at night from 12–16 weeks to about 36 weeks, it lowers the chance of early pre-eclampsia in women at higher risk. At this dose it is considered appropriate for the baby, but take it only on medical advice.
Which BP machine should I buy for home?
Choose an automatic upper-arm machine validated for pregnancy rather than a wrist device. Sit quietly for five minutes, rest your arm at heart level, take two readings, and bring the machine to a clinic visit so we can compare it with ours.
Will BP tablets affect my baby?
These three medicines - labetalol, nifedipine and methyldopa - have decades of use behind them in pregnant women and are regarded as suitable. Leaving high BP untreated is the bigger risk to the baby.
Can I have a normal delivery if I have pre-eclampsia?
Often, yes. Induction of labour aiming for a vaginal birth is reasonable for many women, and an epidural can help with BP control. A caesarean is chosen when delivery is urgent, when the cervix is very unfavourable in severe disease, or for other obstetric reasons.
Does pre-eclampsia affect the baby?
It can reduce blood flow through the placenta, which can result in a small baby, low amniotic fluid or an early delivery. That is why growth and Doppler scans are part of the monitoring.
Can I breastfeed while taking BP medicines?
Yes. Labetalol, nifedipine, amlodipine and enalapril are compatible with breastfeeding. Methyldopa is usually changed after delivery because it can worsen low mood.
Will pre-eclampsia come back in my next pregnancy?
The chance is about one in six overall, and higher if it was early or severe last time. Aspirin from 12 weeks and a monitoring plan from the first visit lower that risk.
How is pre-eclampsia different from eclampsia?
Pre-eclampsia is high BP with signs that organs are involved. Eclampsia is a seizure in a woman with pre-eclampsia. It has become uncommon where pre-eclampsia is recognised and treated, and magnesium sulphate given to women with severe features greatly lowers the chance of a seizure.