Your baby is the size of a...what?

Let me say up front that I have no new news to post about our developing baby here at 18 wks and 2 days.  We have our formal ultrasound scheduled for early next week that will tell us whether we are going to be having a little LaVitrius Byrne or a little Money (pronounced Monet like the artist) Byrne.  Actually Money could be a boys name not just a girls, but that's besides the point.  That being said, I thought I would take a minute to examine a trend that we've noticed in pregnancy literature- both online and in print form.  This trend is to compare the size of your current pregnancy (fetus/conceptus/product of conception to be politically correct for those of you who don't yet consider little Money Byrne to be a human life) to various items. This trend may be well known to those of you that have been through pregnancy before, but to us it is rather confusing.  These items are myriad in nature but most often involve vegetables.   According to some sources, Money Byrne is the size of a sweet potato.   According to others, little Lavitrius Byrne is the size of a turnip.  Who do we believe?  Isn't there some sort of expert consensus on this type of thing?  I would like to think that somewhere experts have gotten together and found the median weight and size of all different varieties of turnips and sweet potatoes in order to reliably predict which vegetable to which we should be comparing our unborn child.  Are we talking Macomber turnips or the Brassica rapa variety?  I'm assuming somebody has looked into this or am I placing too much faith in the internet?  Let's not even get into the size of the uterus (for those who are wondering Heather's uterus is currently the size of a cantaloupe).  Why can't we pick a more standardized system if we are going to be labeling the size of our little L-a ("Ladasha" for our 5 faithful blog followers) Byrne?  Why can't we say that this week, your baby is the size of a baseball and your uterus is the size of a dodgeball (not the hard kind but the softer kind that don't hurt as much)?   If I say your baby is the size of a deck of cards and your uterus is the size of a softball then you know exactly what I'm talking about.  If I say your baby is the size of a of a sweet pea or a papaya, I might as well be telling you your baby is the size of a large rice pudding and your uterus is the size of a small pot roast.  You would have no idea what I'm talking about.  Sorry for the rant I just had to get that off my chest.  We'll update next week once we officially know whether to expect a little Tayshawn or a little Brianida Byrne!