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Gender reveal

It’s good to know when your baby’s sex or gender can be determined by ultrasound. But deciding whether you’ll find out is a whole different question. Here’s what you need to know and some things to consider before you make the call…

Can I find out the sex of my baby?

If you decide you want to know what sex your baby will be, you may be able to find out at your anomaly scan. This is usually offered between 18 and 21 weeks of pregnancy (NHS, 2018). The anomaly scan is mainly to look for physical anomalies in the baby but you can also ask to find out your baby’s sex (NHS, 2018).

If the baby is in the right position, your sonographer might be able to tell you whether you’re having a boy or girl. If not, you may be asked to walk or jump around, or drink some cold water to make it move. Yep, seriously.

The only snag is that it’s not an exact science and sometimes it’s difficult or impossible to tell (NHS, 2018). That’s why some hospitals have a policy of not telling parents the sex of their baby (NHS, 2018)

If the sonographer can’t see your baby’s genitals, you could pay for a private scan another day (NHS, 2018). You might also have another opportunity to find out if you have another scan later in pregnancy.

Some parents might also be able to find out the sex of their baby if they choose to test for certain genetic disorders. Those tests include:

  • CVS (chorionic villus sampling)
  • amniocentesis (where samples of the placenta or amniotic fluid are taken for testing)
  • NIPT test (non-invasive prenatal tests). 

These tests is primarily check for genetic conditions, such as Down’s syndrome and rare inherited disorders (RCOG, 2011). Yet they can also tell you the sex of your baby, depending on the type of test (Great Ormond Street, 2014; Brighton and Sussex University Hospitals, 2016).

The NIPT blood test can be used as early as seven weeks into pregnancy. But the test is most sensitive from 20 weeks onwards (Devaney et al, 2011)

The NIPT test analyses fragments of your baby’s DNA in the mother’s blood and is non-invasive (Devaney et al, 2011). It’s unlike the invasive tests that take fetal cells from placenta or amniotic fluid and can increase the risk of miscarriage (RCOG, 2011; NHS, 2018).

Does everyone find out the sex of their baby before birth?

Not all parents want to find out the sex of their baby and you’ll only be told if you want to know (Kearin et al, 2015). Around 70% of women wanted to know the sex of their baby (Kooper et al, 2012; Ralph and Polson, 2012; Kerin et al, 2015).

Your view of the world and your culture might influence whether or not you find out (Kotila et al, 2014). People’s reasons vary.

The main reasons people gave in one study for wanting to find out were:

  • curiosity (78%)
  • just wanting to know (68%)
  • because it is possible (67%).  

(Kooper et al, 2012)

The main reasons for not wanting to find out were:

  • surprise at birth (94%)
  • it’s more fun not knowing (92%).

(Kooper et al, 2012)

How accurate is finding out the sex of a baby through a scan?

It’s rare to be told your baby’s sex incorrectly.

Experienced sonographers were 100% accurate in predicting sex between weeks 13 and 14 of pregnancy in two studies (Efrat et al, 2006; Kearin et al, 2015). But they couldn’t predict the sex for 3% of babies at weeks 13 to 19 (Efrat et al, 2006). Prediction at earlier stages of pregnancy is less accurate (Kearin et al, 2015).

Can I have an abortion due to the sex of my baby?

Abortion on the grounds of sex alone is illegal in England, Wales and Scotland. However, some serious conditions that are sex-related might fulfill the legal medical criteria to terminate a pregnancy (Department of Health, 2015)

Other things to consider

  • If you’re particularly hoping for one sex or the other, would you rather know earlier if it goes the other way – to get your head around it?
  • If you find out the sex, will you tell everybody else or will you keep it to yourselves?
  • Do you and your partner agree on the decision you’ve made?
  • Remember that you can only find out the biological sex of your baby.  You cannot see or determine its gender in terms of whether it will identify as male or female in society.

Pros of finding out your baby’s sex

  1. You can plan ahead more, especially if you prefer gender specific clothes or nursery décor. This is also handy if you’ve already had other children so want to know what to keep and what to take down to the charity shop.
  2. You can cut down your name debates by half.
  3. Some people say that knowing the baby’s gender can help with bonding.
  4. You don’t have to wait or resist asking during your scan. So if you’re not a particularly patient person, this could be a big benefit.

Pros of waiting to find out your baby’s sex

  1. You get the exciting moment of finding out when you give birth.
  2. You won’t get loads of pink or blue baby stuff bought for you when the baby’s born – a bonus if you prefer non- gender specific colours.
  3. It might not be possible to find out anyway if the baby is in the wrong position and then you might be disappointed.
  4. The verdict might be wrong anyway, as checking for a baby’s gender during a scan is not an exact science so you could get a shock when you give birth (Chigbu et al, 2007).
  5. Everything you choose will be gender neutral, so you’ll be set if you have more children too.

This page was last reviewed in October 2018.

Further information

Our support line offers practical and emotional support with feeding your baby and general enquiries for parents, members and volunteers: 0300 330 0700.

We also offer antenatal courses which are a great way to find out more about birth, labour and life with a new baby.

Brighton and Sussex University Hospitals (2016). CVS and amniocentesis. Available from: [Accessed 9th February 2019]

Chigbu C, Odugu B, Okezie O. (2007) Implications of incorrect determination of fetal sex by ultrasound. International Journal of Obstetrics and Gynecology. Volume 100 (3):619-621. Available from: [Accessed 9th February 2019]

Department of Health. (2015) Assessment of termination of pregnancy on grounds of the sex of the foetus Response to Serious Crime Act 2015. Available from:  [Accessed 9th February 2019]

Devaney S, Palomaki G, Scott J. (2011) Non-invasive fetal sex determination using cell-free fetal DNA. JAMA. 306(6):627-636. Available from: [Accessed 9th February 2019]

Efrat Z, Perri T, Remati E, Tugendreich D, Meizner I. (2006) Fetal gender assignment by first‐trimester ultrasound. Ultrasound in Obstetrics and Gynaecology. 27(6): 619-621. Available from: [Accessed 9th February 2019]

Kearin M, Pollard K, Garbett I. (2015) Accuracy of sonographic fetal gender determination: predictions made by sonographers during routine obstetric ultrasound scans. Australasian Society for Ultrasound in Medicine. 17(3):125-130. Available at:  [Accessed 9th February 2019]

Kooper AJ, Pieters JJ, Eggink AJ, Feuth TB, Feenstra I, Wijnberger LD, Rijnders RJ, Quartero RW, Boekkooi PF, van Vugt JM, Smits AP. (2012) Why do parents prefer to know the fetal sex as part of invasive prenatal testing? ISRN Obstetrics and Gynecology. 2012:524537. Available from: [Accessed 9th February 2019]

Kotila LE, Schoppe-Sullivan SJ, Kamp Dush CM. (2014). Boy or girl? Maternal psychological correlates of knowing fetal sex. Personality and individual differences. Vol 68: 195-198 [Available from:] [Accessed 9th February 2019]

NHS. (2018) Can I find out the sex of my baby? Available from: [Accessed 6th November 2018]

RCOG (2011). Chorionic villus sampling and amniocentesis. Available from: [Accessed 9th February 2019]


Ralph K, Polson D. (2012) A woman’s decision to know the sex of her child prior to birth. Ultrasound 20(3):161–164. Available from: [Accessed 9th February 2019]

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