Choosing whether to learn the gender of your baby is an important decision for many expectant mothers and fathers. Although some prefer the element of surprise, an estimated 50 percent to 70 percent of parents-to-be decide to find out their baby's sex before giving birth, says Pregnancy-Info.net. Methods of determining fetal gender include ultrasound, amniocentesis and CVS--chorionic villus sampling, writes Dr. Elizabeth Pryor for Parents website. The timing and accuracy of the prediction depend on the procedure.
Basics
Most couples learn the sex of their child during an ultrasound performed between 18 and 22 weeks, says the pregnancy website The Bump. According to the March of Dimes, chromosome tests that include CVS and amniocentesis can be performed as early as 10 and 15 weeks, respectively. These tests tend to predict gender more accurately than ultrasound, which relies on visual confirmation; however, CVS and amniocentesis are rarely used for the sole purpose of determining gender.
Ultrasound
Ultrasound is a procedure that uses sound waves to create a sonogram--an image of the inside of the womb. According to the March of Dimes, 70 percent of women have an ultrasound during pregnancy. The procedure is used for various reasons, from determining the fetus' age to checking for complications.
Ultrasound is not a foolproof method of determining a baby's sex, warns The Bump. The effectiveness of the procedure can vary depending on the quality of the sonogram machine and the sonographer. The baby's position within the womb also affects an ultrasound's accuracy, Pryor explains.
Chorionic Villus Sampling
CVS is used during the first trimester to check for genetic disorders such as Down Syndrome and Tay-Sachs disease. The test can be performed either transcervically--through the cervix--or transabdominally, according to the March of Dimes. Both ways involve taking a small sample of the chorionic villus tissue for evaluation. Though generally considered safe when performed by an experienced practitioner, CVS can cause bleeding, infection and miscarriage.
Amniocentesis
Amniocentesis is another type of chromosomal testing. Performed during the second trimester, the procedure involves using a needle to withdraw amniotic fluid from the uterus. Like CVS, amniocentesis is not without risk and is typically only performed to look for birth defects, says The Bump.
Traditional Gender Predictors
Some parents-to-be may wish to forgo science when determining their child's sex. A traditional, non-scientific gender test uses a wedding ring tied to a piece of string. The expectant mother dangles the ring in front of her belly; she will have a girl if it moves in a straight line and a boy if the motion is circular. Other gender myths include analyzing urine--clear for a girl, yellow for a boy--and fetal heart rate. Faster than 140 beats per minute indicates a girl, slower indicates a boy.
