When my husband and I decided to try to have a baby we talked of our hopes and dreams for the yet to be conceived child. We both envisioned a boy first, followed by a girl, and even talked of a third whose gender was not speculated. We by no means only wanted a boy, and would not have really cared one way or the other. In our idealized picture of our family, though, there was always the first born older brother looking out for his sibling(s). As the years went by (without us having a child of either gender) we encountered many friends and family who had boys first, girls first, second children of the same or different sex, and unfortunately, some who had given birth to stillborn and disabled children. As we watched our friends become parents of precious baby girls and boys we realized that the gender meant nothing at all and that our foremost concern was to have a healthy child, boy or girl.
So, when we finally entered our IVF class with five other couples we had completely abandoned any thought of what gender we hoped to conceive. We simply wanted to conceive, period. That is why we were a bit taken aback when we learned that a couple in the class was there solely in an effort to have a girl. They already had male children and were undergoing IVF with PGD in an effort to ensure that their next and final child would be a girl. This statement prompted others in the room to ask questions regarding IVF and gender selection. One couple had heard that boys were more common in IVF and that was a concern because of a genetic condition in their families that was only passed to boys. Another woman was of advanced maternal age and wanted to have a boy to carry on the family name considering that if she conceived it would be her only child. She hoped that the rumor was true!
The nurse talked more about PGD than anything. PGD allows for the transfer of only embryos of the desired gender. She explained that although it is more costly, PGD is the only method of gender selection with a high success rate. She did mention, though, that IVF does seem to have a slight tendency to result in more male babies. A study by an Australian embryologist published in 2006 did find that embryos conceived using the IVF technique and allowed to grow to the blastocyst stage did have a higher chance of being male. The findings indicated that doctors choose to use those embryos which are dividing fastest and that these embryos tend to be male. Overall, the report concluded that there is a 56% percent chance of a male baby if an embryo is conceived using IVF and grown to the blastocyst stage.
My rudimentary research, consisting of scouring fertility boards and looking at the genders of the babies conceived, does not seem to show a clear connection between IVF and the gender of the babies. In looking at my personal experience of having one boy and one girl that were both at the blastocyst stage when transferred, I would have to say that the odds to me look about 50/50. Overall, I guess that there may be slightly more boys born via IVF but there are also more boys born each year in general. My unsolicited advice is that if you are dead set on having a boy don’t rely on IVF without PGD to make that happen!