Will I Have a Boy or a Girl? Predicting Your Baby’s Gender

Having a boy or a girl?

Do your chances of having a boy or a girl change, depending on your family composition? Image by Rotorhead

Do Boys or Girls Run in the Family?

Although it would seem that a couple with four boys (or four girls) has some condition that makes it more likely that the fifth child will be the same gender, that’s not actually the case – In 1979, Rogers and Doughty studied thousands of households to determine whether boys or girls “run” in a family. Their answer was a clear “No” – so, statistically speaking, every child has just about the same chances – there are no ‘runs’ of any gender.

Will I Have a Boy or a Girl?

If you’ve recently had a positive pregnancy test, but are not far enough along for an ultrasound, you may be eager to learn your baby’s gender, if for nothing else to give you ideas for decorating a nursery. Unfortunately, math can’t help you – but technology can. A routine ultrasound scan, as part of prenatal medical care, will give you the most reliable baby gender predictor. You can clearly see the gender of the baby in the second trimester ultrasound in the majority of cases, so your question will be answered soon.


Rodgers, Joseph Lee and Doughty, Debbie. Does Having Boys or Girls Run in the Family? (2001). PDF in American Statistics Chance magazine. Accessed April 7, 2013.

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  1. I wonder, if I had known in advance, would it have changed anything? Hmmmm. Thanks for the explanations here.


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