Pregnancy tests and scans

Antenatal appointments | CVS and amniocentesis | Miscarriage

Antenatal scans

Deciding about screening | Dating scan | Nuchal translucency scan | Anomaly scan

Just as you're being assailed by hormonal upheavals and physical indignities, you're faced with some fairly major moral and ethical dilemmas, too.

Do you want to know the chances of your baby having an abnormality? Would you have an invasive test if it meant risking miscarriage? What if your baby was found to be at high risk of having something wrong? Would you have a termination?

As one Mumsnetter puts it: "The problem with all antenatal tests is that we then have to make choices. It's great if we get the result we want (although nothing's guaranteed with these tests) and not so great when we don't." Cam

And another says: "I would terminate for a condition incompatible with life. But there's a difference between incompatible with life, and incompatible with my life, IYSWIM?" wannaBe

A degree in statistics also comes in handy because what the screening tests do is give you a mathematical possibility (risk) of your baby having certain conditions based on complex factors to do with your age, family history and the results of the tests themselves. 

But the real crunch for many women is that some of the tests have a risk of miscarriage (another statistical nightmare) and none of them is 100% reliable, so some health problems will remain undetected.

Even if the odds are very long, it's your baby so the stakes are sky high and, logically or not, you can feel the odds are stacked against you.

"I guess even if your risk assessment is one in 2,000, someone has to be 'the one'." Hayley

"I wasn't asked if I wanted a nuchal scan, my doctor just assumed I would have it. I was given a really low risk factor (something like one in 4,000) which made us happy but then the radiographer said 'of course, this doesn't mean that your baby isn't the one'. It really upset me - but she was probably only trying to be helpful." Ghosty

To put this in some sort of perspective, more than 95% of pregnancies in the UK result in the birth of a healthy baby and only about 2% of babies are born with major abnormalities.

"If it's your child who turns out to have health problems, there is lots of support from people who know the score in our special needs forum. As one Mumsnetter puts it: "I think the thing that people really don't understand until they have a disabled child is that you love that child every bit as much as your other children. So you don't do things through duty, or because you feel sorry for them - everything you do is because you love them. And you get the same pleasure from being with them and their company as you do from your other children." jimjamshaslefttheyurt

Do I have to have the screening tests?

You're under no obligation to have any tests at all during pregnancy, although most women do have the non-invasive tests so they know how their baby is doing in there. You should be given information about the tests and you'll have to sign a consent form.

Some women want to know of any detectable health issues at the earliest opportunity to avoid a late termination; others wouldn't consider a termination but want to know anyway.

"I have a friend whose daughter has Down's - this was picked up by a nuchal fold scan and confirmed by amniocentesis. Although she never considered terminating the pregnancy, it gave my friend time to plan for her daughter's arrival." Sweetie

And others simply don't want to know. "What is there to prepare for?" asks one mum. "We don't say 'I want to prepare for having a child that has no disabilities,' so why the need to prepare for one that does? I think it's part of what I'd call a trend towards 'pregnancy insurance' - the desire to protect oneself from anything perceived as 'risk'. And that risk is always centred around Down's syndrome, and it's all very negative, where in fact, this is the least worrying syndrome that can be picked up in the scans available to women."

No one can make the difficult decisions for you, but the experiences and opinions of those who've had to make the decisions for themselves can help prepare you for whatever the tests and scans show up. Don't agonise alone, get support from other Mumsnetters.

What you'll be offered

It varies between different parts of the UK what screening tests and scans are on offer, so ask your midwife or GP what's available at the hospitals in your area.

All tests have to meet national guidelines and the National Institute for Health and Clinical Excellence (NICE) sets out the antenatal screening tests women in England and Wales should be offered.

Scotland sets its own guidelines, and Northern Ireland generally, but not automatically, applies the NICE guidelines.

There are routine scans that you'll be offered from quite early in pregnancy. Thankfully, most women find out there baby is developing normally. But it's hard not to be a bit anxious about what the antenatal scans might reveal and it's worth thinking about who you want with you in case the scans indicate all's not well

One mum says: "I went into the scan all happy to see the baby, never really expecting any problems, and came out in bits. I just feel so weighed down by worry."

Another mum who had upsetting news says: "I just feel really odd, especially when I tell people I am pregnant. I feel like saying, 'but...'. It's not quite the celebration I thought I would be having."

What is a dating scan?

This is an ultrasound scan offered when you're between ten and 14 weeks pregnant. High-frequency sound waves are bounced off your stomach to create an image of the baby.

The sonographer doing the scan will be able to tell if the baby's alive, whether you're expecting twins and measure the size of the tiny foetus against the date of your last period.

Ultrasound is painless - the gel that's spread on your abdomen is a bit chilly but nothing more - and there's no evidence it harms you or your baby.

The most uncomfortable bit is having to drink pints of water to fill your bladder (it helps get a better image of your uterus) and then worrying about public incontinence when your ultrasound slot is later than scheduled.

As one mum puts it: "Having to drink all that bl**dy water before a scan only to find there's a delay before your appointment and then you feel like you're going to explode. I'll never forget one nurse asking me (when they were nearly 30 mins over time), 'Do you think you could just pop to the loo and let just a little bit out!!!!' Errrr - NO!!!!" JonesTheSteam

"If you have a toddler in tow take plenty of activities/ treats for them plus nappies etc, the waits can seem endless to a two year old. And don't (as I did - twice) get all the way there and realise you've left your notes at home." Haley

What is the nuchal translucency scan?

Hospitals are meant to offer a nuchal translucency (NT) scan between 11 and 14 weeks to screen for Down's syndrome. It measures the thickness of the nuchal pad (pocket of fluid at the back of the baby's neck), which is related to the risk of Down's syndrome - the more fluid there is, the more likely it is your baby will have Down's. 

"I was not offered a nuchal scan but had read up about it and chose to have it done privately as I was 42 when I became pregnant. I was told my 'risk' was low, at one in 250, but then went on to have a baby with a rare medical condition (now resolved) of one in 4,500! We tend to think everything can be tested/ screened etc, when the reality is that these tests can't check for every possible 'abnormality'." Lindy

"You only have to look at threads on Mumsnet about nuchal results to see the fear and worry it causes. If we could test for other things most of us would be nervous wrecks throughout pregnancy." EyeballsintheSky

Other tests you may be offered/ need to pay for if you want them are the:

• Combined test (should be offered between 11 and 14 weeks), which is a nuchal translucency scan, plus blood tests
• Integrated test (also known as the alpha-fetoprotein, or AFP test)
• Triple blood test (also known as the Bart's test or Leed's test)
• Quadruple blood test

These blood tests - spread over a few weeks - measure specific markers in your blood that can be used to estimate your risk of having a baby with Down's syndrome, trisomy 18 (Edward's syndrome) or neural tube defects

They have to be done at specific times during your pregnancy. Our useful links will point you to detailed information about these tests.

These are all 'non-invasive' screening tests, which means they don't affect your baby

They don't provide a diagnosis, instead they indicate if you have a higher than expected risk (for your age, family history and so on) of certain conditions. If you do, you'll be offered 'invasive' diagnostic tests - chorionic villus sampling or amniocentesis.

What is the anomaly scan?

This is an ultrasound scan offered between 18 and 20 weeks of pregnancy. It checks your baby's growing well, looks at all your baby's major organs and limbs, face, head and brain, and checks the position of the placenta.

It can pick up serious problems (something to bear in mind if you're thinking of taking other children along) and, if it does, you'll be offered further tests (amnio and CVS) to make a more definite diagnosis.

And to give you a taste of what lies ahead - ie babies don't always do what you want them to - how much the scan shows may be affected by your baby's position at the time of the scan.

Antenatal appointments | CVS and amniocentesis | Miscarriage