Since the beginning of time, predicting the sex of an unborn baby has been a pastime of healers, grandmothers and astrologers. Now we can add doctors to the list, as determining the gender of a fetus has never been done more accurately.Around 70% of parents who have the opportunity to learn whether their baby is a boy or a girl before the birth will opt to do so: the rest want to keep it a surprise. The most important reason for knowing the sex of the fetus is in the case of sex-linked genetic diseases. If a particular disease runs in the family and only occurs in one sex, parents may well be concerned about their baby's chances of having the disease. The other reason is curiosity: some people want to know in advance so they can have the name, nursery and wardrobe all lined up.
Ultrasound is most commonly used for determining the sex of a baby, since it's non-invasive and relatively simple. The genders tend to be fully differentiated at around 12 weeks after conception, so as long as the technician or doctor can get a clear view, the chances of getting it right are high. After the 12th week of pregnancy, accuracy approaches 99%.
Sometimes the doctor will test for illness, disease or fetal abnormality by using amniocentesis; a procedure in which a sample of amniotic fluid is extracted and tested. If you're having amnio done for another reason, you can also have the sex of the baby determined, but because amniocentesis carries risks of miscarriage or infection, you'd only use it for sex determination if something else is being tested for. Chorionic villus sampling (CVS) is another test used to look for genetic disorders: in this case, a small sample of the sac where the baby develops is taken from the mother. This sample can also be used in a secondary fashion to determine the baby's gender.
The pros and cons of learning your baby's gender are simple, but the psychological effects can be great. If you are sure you're carrying a much-wanted son but find instead that your baby will be a daughter, it may cause you some dismay. Inheritances may be affected in families that only pass assets on to one gender. Because ultrasound determinations aren't 100% accurate, there is a 1-5% chance that you will be told your baby is a boy when it's a girl, or vice versa. If you don't mind surprises, that's fine, but if you've been making decisions about nursery school waiting lists, nannies vs mannies or pink vs blue, you may find yourself in a middle of a gender confused nursery. Get the best information you can by making sure the person who interprets the ultra sound photo feels very confident in the prediction. If the picture is unclear, you may want to wait and have the ultrasound done at a later time.
