One of the most exciting times of your pregnancy is when you finally get to take a peek at your baby inside the womb. The anatomical ultrasound is a detailed look at your growing baby, and it's the time when you are likely to find out if you're having a boy or a girl. According to "Parents" magazine, an experienced sonographer predicts the gender accurately about 95 percent of the time, although nothing is certain until delivery day. While it's fun to use old wives' tales to predict your little one's sex, you'll never forget the moment when the technician reveals what her experienced eye actually sees.
First Trimester Ultrasounds
You are likely to have more than one ultrasound during your pregnancy as part of your routine prenatal care. Possibly the first is a transvaginal ultrasound, which is performed on women in the very early stages of pregnancy. This early, the baby is in embryonic form and has not yet developed recognizable features. Many women have abdominal ultrasounds in their first trimester at around 10 or 11 weeks, but at this stage of a healthy pregnancy, it's highly unlikely that you'll find out your baby's gender. Keep in mind that the baby's genitals aren't formed until around the 11th week, according to BabyCenter.com.
Once you have your first abdominal ultrasound, you'll likely hear your baby's heartbeat. What first may sound like galloping horses is actually your little one's heart beating rhythmically before you can even feel him move. There's a common belief that the heartbeat at this time is an indication to the sex of the baby. It's not an exact science, but according to Patricia Crane, director of the nurse-midwifery service with the University of Michigan Health Services, fetal heart rates between 110 to the lower 130s indicate a boy and heart rates in the 140 to 160 range indicate a girl. Heart rates between the mid-130s to 140 are more difficult to predict. Bear in mind, this is more of an educated guess during the first trimester, according to WebMD.com.
The Level II Ultrasound
During the second trimester -- usually between the 16th and 20th week of pregnancy -- the doctor orders a level II ultrasound, which many refer to as the "anatomical ultrasound." Many mothers-to-be see this as an opportunity to find out the gender of their unborn baby. The level II ultrasound is performed in the same manner as the first ultrasound, except that the doctor gets a more detailed look at specific areas of the developing baby. By this time, the baby's genitals have formed, and if she cooperates, the doctor or technician is able to determine the sex. Be sure to let your practitioner know ahead of time if you want to keep the baby's gender a surprise. Although the level II ultrasound for gender determination is pretty compelling, misinterpretations are still possible.
Higher-risk mothers-to-be are offered a chorionic villus sampling test in their first trimester to screen for various birth or genetic defects. The test involves taking cells from the placenta and analyzing them. The CVS test allows for gender to be determined at the earliest point possible, to rule out gender-specific diseases such as muscular dystrophy. There are risks involved with the test, such as miscarriage, and it is done only on a special-case basis. The test is done at 10 weeks at the earliest, and this is the only time that a baby's sex can be accurately determined in the first trimester.