Baby-making seasons in Egypt

I knew that life in Egypt was seasonal because of the behaviour of the Nile, the river that defined the lives of the people who lived of it. It is well known that the Nile floods during the summer months and that Egyptians arrange for their agricultural activities accordingly. What I did not know was that also the sexual life of the Egyptians was seasonal!

It looks like the peak of sexual activity can be restricted to the summer months of July and August. Excavations of a cemetery of the Dakhlesh Oasis in south-west Egypt revealed the bones of several pregnant women, who lived in the Roman city of Kellis. Live Science reports that “researchers have uncovered 765 graves, including the remains of 124 individuals that date to between 18 weeks and 45 weeks after conception. The excellent preservation let researchers date the age of the remains at death. The researchers could also pinpoint month of death, as the graves were oriented toward the rising sun, something that changes predictably throughout the year”. (http://www.livescience.com/32078-ancient-egypt-cemetery-reveals-sex-season.html)

I suppose that the archaeologists combined the above complex information to come up with the astonishing conclusion that most of the Egyptian had sex during the summer months, while conception was minimal around January. The issue that I have with these results is whether we are looking into the sexual activity of the Egyptians or the peak of their fertility. How could we distinguish one from the other?

Photo by Gillberto Santa Rosa from Rio De Janeiro, Brazil. To be found in Commons Wikimedia http://commons.wikimedia.org/wiki/File:Sperm-20051108.jpg