“Maybe you just can’t carry boys?” I was pregnant for the fourth time, this time with a daughter, and I think in saying this, she thought it would give me comfort. This time, my pregnancy was different. This time it was a girl. All I could think of was Anne Boleyn. She couldn’t have a boy either, and look what happened to her! Besides being plagued by multiple pregnancy losses (sources are not clear on whether she lost two or three babies), her failure to produce a male heir meant her husband arranged to have her executed. A high price to pay for being, in modern medical terms, a habitual aborter.
So is it true? Are there some women who just can’t carry boys? Maybe not, but recent research has confirmed there is a link between boy babies and stillbirth. Researchers at the University of Exeter looked at studies from around the world to see if there was a connection. They examined the numbers from 21 different studies conducted in 24 different countries, from Australia to Venezuela, the UK and US, as well as China and India. Overall there were over 30 million records.
And sure enough, the researchers found that boys are more likely to be stillborn than girls. This was true in every country studied, except for a couple where sex selection of fetuses is known to be an issue. The difference was about 10%, which means that male babies are 10% more likely to die before birth than female babies. Not a huge difference, but about the same as the risk caused by smoking. They don’t know why this might be the case, and the best they can come up with is speculation based on what happens in animals, where male babies are more susceptible to stress or the effects of a poor diet. Also, despite the huge study, there were some limitations to it. When searching for articles to include, they looked for articles that mentioned gender, so studies where the differences were unremarkable might have been missed. Also, they weren’t able to make a difference between stillbirths that happen before labor or during labor, which might have an impact.
So what does it mean for you? Maybe not much. If you lost a boy, it is cold comfort to know that his gender might have played a role. If you are pregnant with a rainbow boy now, the increased risk isn’t enough to worry about, and besides, you can’t make changes at this point anyway! And despite what happened to Anne Boleyn, there is no evidence that certain women can’t carry sons. Who knows what her next baby might have been, had Henry VIII not decided to have her head cut off? After all, once my daughter was born safely, I went on to have another pregnancy. A son. He’s 3 now and I think he turned out okay.
To read the study in full, it is free online. Find it at:
Mondal D, Galloway TS, Bailey TC, Mathews F. Elevated risk of stillbirth in males: systematic review and meta-analysis of more than 30 million births. BMC Med. 2014 Nov 27;12:220.