Pre-eclampsia and high blood pressure in pregnancy
Routine monitoring for pre-eclampsia during pregnancy
As part of ‘routine antenatal care’, pregnant women are offered regular checks and tests at their appointments with doctors and/or midwives. Checking a pregnant woman’s blood pressure, urine and blood is part of this ‘standard’ medical care. Picking up pre-eclampsia can be a case of trying to piece together a ‘jigsaw’ of signs and symptoms which can change over time. These jigsaw pieces might include high blood pressure readings or results from testing for protein in the urine.
Some women we talked to were offered extra monitoring because they had possible ‘risk factors’ for pre-eclampsia. Extra monitoring often meant being seen more frequently than the standard ‘routine’ antenatal appointments and being seen by different health professionals instead of, or in addition to, the ‘standard’ antenatal care team of GPs and/or midwives. Ruth X had “consultant care” with her second baby because she had developed gestational diabetes and had pre-eclampsia in her first pregnancy. Because Philippa had pre-eclampsia in her first pregnancy, she saw her midwife fortnightly and had regular appointments with a consultant during her second. This extra care made her feel “really well looked after” and “added to me being calmer”. However, not all women found the extra monitoring helpful.
Ruth X had extra monitoring from 28 weeks into her first pregnancy through a specialist maternity care unit.
Ruth X had extra monitoring from 28 weeks into her first pregnancy through a specialist maternity care unit.
Abigail was classed as having a ‘high risk’ pregnancy and was seen by a consultant for her antenatal care, but didn’t find this very helpful.
Abigail was classed as having a ‘high risk’ pregnancy and was seen by a consultant for her antenatal care, but didn’t find this very helpful.
Samples of urine are regularly checked for protein (proteinuria). Normally, when the kidneys are working well, protein is filtered out of the blood. Pre-eclampsia can cause damage to the kidneys which make them less effective at removing the protein, although there can be other causes too for leaking protein into the urine.
Testing for proteinuria involves using a dipstick to test the urine, which changes colour depending on the result. If the dipstick shows there is protein in the urine, then more detailed tests may be carried out. Other tests can give more detailed information, for example by indicating how much proteinuria is present. Proteinuria was sometimes measured as a single positive number: 1+, 2+, 3+ or 4+ based on ranges of grams of protein in the urine.
Emma gave a urine sample when she was first admitted to hospital. The nurse asked for a second sample to check the results, which showed proteinuria.
Emma gave a urine sample when she was first admitted to hospital. The nurse asked for a second sample to check the results, which showed proteinuria.
So, I got there and I remember quite a sort of assertive nurse told me to take a urine sample, and then she came back and went, "No, no you’ve got to take another one; you’ve not done it properly." And then I came back and did another one and she went, "Ah," because I'd had obviously a high protein read and she wanted to check it was right.
And then she took my blood pressure and she just sort of said, "Yeah you're not going home," and tagged me and put me in a bed so [laughs].
So it was very quick, it was, you know it was no hanging around.
Blood tests were often taken at antenatal appointments. There are lots of different tests that can be run on blood samples, including one to check the platelet count. Platelets are important because they help the blood to clot and to stop bleeding. Low levels of platelets mean that the woman is at risk of serious bleeding. The results of a platelet count were usually given as a number in the thousands per microliter of blood.
Some women remembered having blood tests taken. Lyndsey was admitted to hospital with high blood pressure and protein in her urine, but she doesn’t remember it being explained why low platelets levels in her blood would be an important result. Paige remembered having lots of blood tests, her arms were full of bruises “where they were just sticking stuff in, pulling blood out”.
Michael thought that his wife’s doctors wanted to deliver their baby by caesarean section quite quickly but there were some delays waiting on blood results.
Michael thought that his wife’s doctors wanted to deliver their baby by caesarean section quite quickly but there were some delays waiting on blood results.
Blood pressure measures the strength that blood is moved around a person’s body through their arteries. Blood pressure is usually measured using a monitor connected to an arm cuff which automatically inflates or by a trained health professional using equipment such as a hand pump and stethoscope. Blood pressure is recorded in millimetres of mercury (mmHg) and readings are made up of two numbers: systolic pressure (the pressure when blood is being pushed out by the heart) and diastolic pressure (the pressure when the heart rests between beats). For example, if a person’s systolic pressure was 120mmHg and their diastolic pressure was 80mmHg then their blood pressure reading would be 120/80.
Blood pressure often changes during pregnancy. Usually, blood pressure goes down for the first couple of months and then, around the half-way point (about 4-5 months), blood pressure tends to rise again back up to similar pre-pregnancy levels. However, for some, blood pressure doesn’t follow this pattern. Instead, their blood pressure may rise up higher than is ‘normal’ or earlier on in their pregnancies. This can indicate a high blood pressure problem, such as pregnancy-induced hypertension or pre-eclampsia. Regular checks track how a woman’s blood pressure is changing and pick up signs of what may be happening or likely to happen later on in her pregnancy.
Dr Khan describes the normal changes to a woman’s blood pressure during pregnancy. Monitoring blood pressure and tracking differences in the readings are important.
Dr Khan describes the normal changes to a woman’s blood pressure during pregnancy. Monitoring blood pressure and tracking differences in the readings are important.
When we measure blood pressure, there are two separate numbers. The first is called systolic blood pressure and the second is call diastolic blood pressure. The reason you have to take two separate measurements is because, over the course of one heartbeat, how high or low the pressure is inside a blood vessel changes. When the blood has been forced out from the chambers of the heart into the large blood vessels of the body, the blood pressure initially is relatively high. When the heart muscle subsequently relaxes, so that the chamber can fill up with more blood to be pushed out over the next cycle, the pressure is relatively low. So we look at both numbers because both are important and sometimes we look at the difference between the two.
Some women showed early signs that they might develop high blood pressure problems in pregnancy. Their doctors usually offered extra monitoring to keep an eye on it. At her booking appointment at 10 weeks, Samantha Y was told she had high blood pressure. She saw a doctor or midwife every two weeks so it could be monitored closely. However, others didn’t feel they were monitored enough. Tracey felt that “you’re left to your own devices”.
Aileen talked about the extra care and monitoring she received in her pregnancy when there were signs she might be developing blood pressure problems.
Aileen talked about the extra care and monitoring she received in her pregnancy when there were signs she might be developing blood pressure problems.
Twenty eight yeah.
And they detected protein in my urine, and then they… just basically the same thing as last time, that we have to keep you in.
Yeh
Well actually before that they…yeah they…I had to have a 24 hour blood pressure monitoring.
Mm OK
So they sent me home with the cuff that I had to keep on all the time, and then I had to bring it back the next day, and then they saw that the blood pressure was quite high all the time, and they decided to keep me at 28 weeks.
However, some women felt they had been dismissed by health professionals. Their message to other pregnant women was to be assertive and determined in asking for medical help. Munirah said, “go to your doctor and don’t take ‘no’ for an answer”. If it turns out that everything is fine, then the test results can be reassuring; if a problem is found, doctors can take steps sooner to make the pregnancy safer.
Olivia noticed that her blood pressure was rising when it was checked at routine antenatal appointments. She felt these readings in combination with her other symptoms should have been acted on sooner.
Olivia noticed that her blood pressure was rising when it was checked at routine antenatal appointments. She felt these readings in combination with her other symptoms should have been acted on sooner.
So then again at 30 weeks I had a midwife appointment – blood pressure had gone up again. I think it was about a 133 at that point, still climbing and I thought, 'Mm yeh still climbing, not good, that’s not good.' So, yeah it was the second hospital visit – I left my desk; I'd left everything logged in, I was like… because the day before I'd had a midwife appointment and my blood pressure had been high there but she said, "Oh it's still a few points below what we admit," and I was like, "Right I'll just go home then," you know like. I'm seeing sparkles; I feel weird; I had pain all round here; I had pain here and I was like, 'It's not good, it's not good.' So I thought, 'You know what, I'm going to be back here tomorrow,' and I thought, 'I don’t want to risk my health,'
So yeah the midwife appointment at 37 weeks when I toddled off from my desk and I never went back. I'd borrowed a phone charger off a friend at work, and I've still not given it back to her because she left the office when I was on maternity leave. But I… I got… she took my blood pressure, it was the magic number – it was over the magic number, I think it was like 160 or something over 90, some ridiculous number which for me was like… I mean I was just… I was swollen so badly – everything was swollen. Like, my friends had been saying like my feet were just sticking out my shoes you know. I was like Michelin man, and my friends were like, "You should really see somebody." I'm like, "I'm seeing people, you know I'm having regular visits for goodness sake." This is… you know it wasn’t being monitored. I felt I had to do more to look after myself. So, I had to do more really to look after myself than I was getting from the community team. I had one really good midwife and I made sure I always went back to her. She was the one who said, "Right, your blood pressure is too high," that day, at 37 weeks.
Helen X had high blood pressure at a routine antenatal appointment. She wasn’t worried about it at first and her GP agreed to let her test it again a few hours later. She was admitted to hospital for more tests when her blood pressure remained high.
Helen X had high blood pressure at a routine antenatal appointment. She wasn’t worried about it at first and her GP agreed to let her test it again a few hours later. She was admitted to hospital for more tests when her blood pressure remained high.
Vicki had high blood pressure a few days after giving birth and returning home with her baby.
Vicki had high blood pressure a few days after giving birth and returning home with her baby.
And then I went and saw the midwife and she said, “Are you okay?” And I said, “No, I haven’t been feeling well.” And when she took my blood pressure, it was the highest that she’d ever taken and I think it was up in the 210s, 150, or 130 or something like that. And so she was, you know, instantly, “You need to lie down. You need to get on your left side. We need to call an ambulance.” And I was rushed back into the [hospital] again. So yeah, and then, you know, they just monitored me. They put me on labetalol and more blood pressure medication, that kind of thing.
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