Is it a Boy or a Girl?

By Audrey Mendenhall RT, RDMS, RDCS, RVT
Sound Health Imaging

ultrasound-boy1-325x263.jpg

So now you’re pregnant.  Are you going to find out the baby’s sex ahead of time or wait to be surprised? This can be quite a dilemma for expectant mothers.  Fortunately, what used to be scarcely more accurate than a coin-toss can now be determined absolutely.

There are some compelling reasons to learn the sex of your baby prior to birth. Maybe you’d rather refer to your baby as “he” or “she” rather than “it”. Some say once they knew the sex of their baby, it became a “real” person and they began bonding. Maybe you want to pick out the name ahead of time. You might want to have a gender-specific baby shower and purchase gender-appropriate newborn clothing. You may want to decorate the nursery. It also may give you time to adjust ahead of time in case you were hoping for the
opposite sex.

On the other hand you might be like many other moms-to-be who choose  to wait until birth. They claim there’s no better surprise. They love hearing the announcement “Congratulations!  You have just had a baby ___________!”   These moms contend that not knowing makes the last few weeks of the pregnancy bearable, and it helps them during labor and delivery. You may be a little on the ornery side and enjoy annoying nosey family and friends by making them wait until the birth of the baby. Or you may really enjoy making phone calls to loved ones from the hospital to share the news of your new little one. 

ultrasound-girl1-325x264.jpgIn either case, this has been an age-old dilemma.  Since the beginning of time, and long before ultrasound, moms have been trying to determine the sex of their baby before it arrives.

The list of wives’ tales to determine fetal gender is extensive. If the baby is carried high; it’s a girl. If it is low; it’s a boy! Actually, uterine musculature and tone or baby position determines how the baby is carried. Pregnant mom’s breasts are also supposed to be telling as to the sex of their baby. A remarkable change in
breast size early in the pregnancy supposedly means the baby is a girl. If by looking in the mirror the right breast is larger, than the baby is a boy. If the left breast is larger, plan on a girl. If both breasts are the same size, does that mean one of each?

And then there’s the “string/thread/pendant test” for determining fetal sex. This is performed in various ways. If the weight on the end of string, thread or pendant swings back and forth; it’s a boy. If it moves in a circular motion, the outcome is thought to be a girl.

Two practicing physicians in Vancouver, British Columbia even went so far as to test three of the more popular theories. First was the Chinese Lunar Chart that was said to have been discovered in a royal tomb near Beijing. This chart, which was buried 700 years ago, uses the mother’s age and the month of conception to determine the sex of the baby. Unfortunately the Canadian Doctor’s found it to only be 55% accurate.  

ChineseConceptionCalendarCombined-600.jpg 
Click Here for larger calendars

Next was the theory that a female’s heart rate is greater than 140 beats per minute, and a male is less than 140 beats per minute. Although this theory had some acceptance in the medical community at one time, it wasn’t proven to be accurate by the BC docs either. Finally, they researched the “Draino Test”. They added 1/4 teaspoon of Draino crystals to 3 ml of urine, producing either a green or brown color. They could not find a consensus among proponents of this fine test as to which color determines which sex. Some said green equals male and brown equals female; others said just the opposite. In either case, the predictability was zilch for predicting fetal gender.

ultrasound-boy2-325x263.jpgBut for all of you “want-to-knowers”, there is some good news. Unlike the old wives’ tales, there are now highly accurate and reliable medical tests available to determine fetal gender. But like most things in life, there are pros and cons with each.

Amniocentesis and Chorionic Villi Sampling are two procedures that are bascially 100% accurate. However, because of their invasive nature these procedures are not used solely for sex determination, but for assessing genetic abnormalities in high risk pregnancies.

There is also a new maternal blood test that has recently been released for sex determination. This test looks for Y chromosome (male) DNA in the maternal blood sample. The kit can be purchased onthe Internet for approximately $265-330, and can be used after the 10th week of pregnancy. It utilizes a finger stick blood sample from the mom-to-be which is returned to the company for testing and results. Many precautions must be taken to avoid contamination of the sample by any male DNA in the area. According to the on-line ads, the accuracy of these varies from 90-95%.

US-boystuff3D-325x246.jpgProbably the best and easiest ways to find out is through an ultrasound exam. In the hands of a skilled sonographer, ultrasound accuracy for fetal gender is approaching 100% after 16 weeks. Even in the first trimester, fetal sex determination has an 80-90% success rate, given the recent technological advances in ultrasound. (At Sound Health Imaging we pride ourselves in our 100% success rate in predicting fetal gender! ?) Since your ordinary pregnancy care includes at least one ultrasound, you simply have to make a request from your sonographer. The downside is that ultrasound is extremely operator-dependent and there are great differences in skill levels among sonographers.

And then there’s the mom that hasn’t had an ultrasound and hasn’t paid any attention to the wives’ tales. When asked what she thinks she is having…….she guesses correctly 71% of the time!  Go figure…..