Your pregnancy

Pregnancy health conditions

8 min read

Health conditions like pre-eclampsia or gestational diabetes which develop during pregnancy can have an impact on your antenatal care and how you plan to give birth.

Share this

Being diagnosed with a pregnancy health condition can come as a shock, especially if you weren’t aware of any risk factors or obvious symptoms.

Having a common condition like pre-eclampsia or gestational diabetes will mean you have more antenatal check-ups and possibly have to adapt your plans for the birth, because your pregnancy will be classified as higher risk. However, it’s very rare for these conditions to pose a serious risk to your or your baby’s health, as long as you get the right treatment.


Pre-eclampsia usually develops in the second half of pregnancy and affects more than one in 20 pregnant women.

You’re more likely to be diagnosed if you’ve had pre-eclampsia in a previous pregnancy or if you have a pre-existing health condition like high blood pressure or a kidney disease; however, all women are at risk of developing the condition.

At every antenatal appointment, your midwife will look out for pre-eclampsia symptoms:

  • high blood pressure
  • protein in your urine
  • blurred vision
  • severe headache
  • severe swelling in your hands and feet.

It’s important that you contact your midwife or doctor straight away if you start to experience symptoms in between your appointments.

Most cases of pre-eclampsia are mild, and you may be offered medicine to help lower your blood pressure and manage the condition. Your maternity team will keep a close eye on you during the rest your pregnancy to make sure the condition isn’t getting worse.

Because the only way to cure pre-eclampsia is to give birth, you may be advised to have an induction or c-section when it’s safe for your baby to be born, usually around 37-38 weeks.

If you’re severely affected by pre-eclampsia, you might be admitted to hospital for monitoring and treatment, and your baby may need to be delivered before you’re full-term and possibly spend some time in special care.

Gestational diabetes

During pregnancy, you need to produce extra insulin for your baby. If your body can’t keep up with the increased demand, you develop gestational diabetes.

One in 20 pregnant women get gestational diabetes, and anyone can develop it. However, you’re a bit more likely to be diagnosed if you have any of the following risk factors:

  • at your booking appointment, your BMI is over 30
  • you’ve previously had a baby weighing 4.5kg (10lbs) or more at birth
  • you’ve had gestational diabetes in a previous pregnancy
  • your parents or siblings have diabetes
  • your family origins are south Asian, Chinese, African-Caribbean or Middle Eastern.

If you have any risk factors, you’ll be offered a glucose tolerance test when you’re 24-28 weeks pregnant.

If you’re found to have gestational diabetes, you’ll be given advice about how to keep your blood sugar in control during pregnancy – through diet and exercise but also tablets or insulin injections if necessary.

Many hospitals have specialist diabetes midwives who will give you advice and support. You can look up your local hospital to see what they offer.

If you have gestational diabetes, you may be advised to be induced before you’re 41 weeks pregnant, or earlier if there are complications with you or your baby. Read our advice on how to negotiate your care if you’ve been told you’re at higher risk of complications during birth.

After the birth, medical staff will keep an eye on your baby’s blood sugar level as it can sometimes become too low. If the doctors are concerned about your baby’s blood sugar levels, they may be admitted to the special care unitYou should also be offered a follow-up blood test for yourself three months after giving birth, to check that your blood sugar levels are back to normal.


During pregnancy, your blood volume increases and a lot of your iron resource goes to your baby. As a result, you could develop a deficiency known as anaemia. One in five women are diagnosed as anaemic when they’re pregnant.

Your midwife or doctor will take blood tests at your booking appointment and your 28-week antenatal appointment to check your iron level. If it’s found to be too low, you could be advised to take iron tablets to help raise it, as a low iron level increases the risk of your baby having a low birth weight or being born prematurely, as well as making it more likely you’ll need a blood transfusion during or after giving birth.

Some tips for raising your blood iron level:

  • Eat more iron-rich foods like leafy green vegetables, lentils, fortified cereals, red meat, fish and poultry.
  • Take vitamin C (for example, orange juice) with your iron tablets.
  • Avoid foods and drinks containing calcium and caffeine for an hour before and after taking your iron tablets.

Many health trusts have a set minimum blood iron level for women planning to have a home birth or have their baby in a birth centre.  If you’re found to be anaemic, your midwife may take another blood test when you’re around 36 weeks pregnant, to make sure you’re at a safe level for the birth setting you want.

If you’re diagnosed with anaemia when you’re more than 36 weeks pregnant, there may not be enough time for iron tablets to work before the birth, so you may be advised to have iron given intravenously.

Placenta praevia

When your placenta forms, it usually attaches itself high up on the wall of the uterus. Sometimes, the placenta is low down, next to or covering the cervix instead, which could make giving birth more complicated.

If you’re found to have a low-lying placenta at your mid-pregnancy scanyou’ll be invited back for another scan when you’re further along, as the placenta usually moves up on its own as your uterus grows.

Only one in ten women who have a low-lying placenta at their 20-week scan go on to have placenta praevia when their baby is born. However, your risk of the placenta staying low down is higher if you’ve previously had a caesarean section.

Your consultant may talk to you about having a planned c-section if the placenta is still next to the cervix when you’re approaching your due date, as you’re at higher risk of heavy bleeding if you give birth vaginally when the placenta is in this position.

If the placenta covers the whole of your cervix, you could be admitted to hospital for monitoring when you’re around 34 weeks pregnant, as you’re at a small but increased risk of suddenly starting to bleed heavily, and you’ll then need to deliver your baby immediately by c-section.

High or low levels of amniotic fluid

Throughout your pregnancy, your baby is surrounded by amniotic fluid in a sac in your womb. The amount of fluid will vary at different stages of pregnancy, but some women have too much or too little amniotic fluid, which can cause problems.

If your midwife or doctor thinks that your bump is measuring larger or smaller than expected at your antenatal appointments, they can refer you for an ultrasound scan where the sonographer will measure how much fluid surrounds your baby.

Polyhydramnios (too much amniotic fluid)

If you have more amniotic fluid than normal, you’re at a slightly increased risk of:

  • giving birth prematurely
  • your baby being in a less good position for birth
  • umbilical cord prolapse (where the cord is born before your baby)
  • something being wrong with your baby (for example a genetic problem or a blockage in the baby’s gut).

Because of these risks, you’ll have extra antenatal appointments to make sure your pregnancy is progressing as expected, and you may be advised to give birth on the labour ward where medical help is at hand. But be reassured, most women with a higher volume of amniotic fluid don’t experience any problems and go on to have a perfectly healthy baby.

To feel a bit more prepared, it can be a good idea to talk through your birth plan in advance with your doctor or midwife, and try to include what you should do if your waters break or you go into labour earlier than expected.

Oligohydramnios (too little amniotic fluid)

It is expected that your amniotic fluid level will drop late in the third trimester, especially if you’re more than 42 weeks pregnant. The most common reason for this is your waters breaking – this can be a gradual leak rather than a big gush, so you may not have noticed it happening.

If your waters have broken, you’ll be offered antibiotics and tests to see if you or your baby have any infections. If your baby is full-term, you may be advised to have an induction to reduce the risk to you and your baby.

Having less amniotic fluid doesn’t cause problems for most women and babies, but you are at a slightly higher risk of:

  • your baby having a low birth weight
  • giving birth prematurely
  • labour complications, for example of the umbilical cord being compressed or there being meconium in your water.

If low levels of amniotic fluid are identified earlier in your pregnancy, there are some other possible causes, including:

  • Problems with your placenta meaning your baby can’t get enough nutrients and blood. This may also be affected by conditions including pre-eclampsia and diabetes.
  • An issue with your baby’s kidneys or urinary system, meaning they are not processing the fluid and producing urine as they should be.

If you’re found to have low amniotic fluid during your first or second trimester, you will be closely monitored during the rest of your pregnancy to ensure your baby is developing as expected.

Finding support

If you’ve been diagnosed with a pregnancy condition, you don’t have to face it alone. In addition to talking to your midwife and birth partner, there are organisations and peer support groups that can help you navigate the world of a higher-risk pregnancy:

More from Which?

  • Pain relief during labour: From gas and air to epidurals – we tell you everything about your pain relief options when giving birth.
  • Inductions and interventions: Find out what to expect from medical interventions such as inductions, forceps and ventouse delivery.
  • Recovery from a c-section: If you have your baby by a caesarean section, your recovery will be different compared to a vaginal birth.
Share this
Advice for every step of your pregnancy

We can support you on your journey as a parent with relevant news, advice and information on Which? services directly to your inbox.