Yes, choosing the sex of your child is technically possible thanks to advances in fertility treatments that allow doctors to create or identify embryos of a certain sex. But today's sex-selection options aren't equally effective, affordable, or available.
The most accurate sex-selection methods are usually the most expensive (tens of thousands of dollars), often involving invasive infertility treatments and fertility drugs with side effects. If you're serious about trying one of these techniques, you'll have to meet strict eligibility requirements, too. In some cases you won't be eligible unless you're married and already have at least one child of the sex opposite from the one you're trying for. Some clinics also have age limits or require you to take hormone tests to prove you're not approaching menopause.
And keep in mind that Mother Nature has already tipped the odds a bit in favor of boys in the sex-selection game. According to data released in 2004 from the National Center for Health Statistics, approximately 1,050 boys are born for every 1,000 girls.
The following gender-selection methods draw from two existing infertility treatments: in vitro fertilization (IVF) and artificial insemination (AI). IVF starts with a round of fertility drugs to stimulate your ovaries to produce several eggs for fertilization, instead of the single egg you normally release each month. Fertility drugs may also be used for AI. For AI, also known as intrauterine insemination (IUI), your doctor uses a catheter to insert a concentrated sperm sample directly into your uterus.
For IVF, fertilization occurs outside your body (in vitro means literally in glass). Your doctor gives you an anesthetic and removes your eggs from your ovaries by inserting a needle through your vaginal wall. Your eggs are then fertilized with sperm in a petri dish. Two to five days later your doctor places the fertilized eggs — now embryos — in your uterus by inserting a thin catheter through your cervix. The number of embryos inserted depends on your age, the quality of the embryos, and your reproductive history. As a general rule, if you're under 35 and the embryos look healthy, no more than two are transferred.
Preimplantation genetic diagnosis (PGD)
An in vitro fertilization (IVF) technique in which embryos are created outside the womb and then tested for genetic disorders and gender.
When PGD was introduced back in 1989, it was used solely to help couples or individuals with serious genetic disorders reduce their risk of having a child who suffered from the same condition. Today PGD is still used for this reason, but is also used commonly when women are 35 or older and/or have a history of recurrent miscarriage. Only a handful of clinics offer the technique for sex selection for nonmedical reasons.
Effectiveness
Almost 100 percent effective.
How it's done
During an IVF cycle, eggs are fertilized with sperm in a petri dish. A single cell or cells are later removed from each of the resulting 3- to 5-day-old embryos and tested for gender.
In a regular IVF cycle scientists try to determine which embryos are normal merely by looking at them under a microscope. But with PGD, the embryos are tested thoroughly for genetic abnormalities and sex. By transferring only healthy embryos to the uterus, you're less likely to miscarry or have a child with a genetic disorder. Prenatal tests such as amniocentesis or chorionic villus sampling (CVS) are still recommended if you're 35 or older because more genetic abnormalities can be detected later in pregnancy.
In a regular IVF cycle, doctors usually transfer two or more embryos to your uterus — the number depends on your age, the quality of the embryos, and your reproductive history. (If you're 40 or older, typically four or five embryos may be transferred.) But in PGD, doctors transfer no more than two because they've already weeded out embryos that are unlikely to implant or to result in a healthy pregnancy.
Pros
• If you do get pregnant, PGD guarantees with almost 100 percent certainty that you'll have a baby of your desired gender.
• Following a PGD cycle, remaining embryos of the selected gender are automatically frozen. These can used in another attempt, if you miscarry or decide you want more children down the road. Frozen embryo transfers aren't as successful as fresh transfers, but the procedure is less invasive and significantly cheaper.
Cons
• A single round of PGD can cost nearly $20,000.
• The procedure is invasive and the removal of eggs from your ovaries can be painful.
• The fertility drugs you have to take can have uncomfortable side effects such as weight gain, bloating, swelling, and blurred vision.
• As with any IVF pregnancy, you're more likely to have multiple births. According to the latest statistics from the Centers for Disease Control and Prevention, 38 percent of infants conceived as a result of IVF and related procedures were twins.
• About 43% of fresh IVF cycles result in a live birth, and that figure goes down as you get older. But some doctors claim higher success rates with PGD because defective embryos are excluded.
• You'll need to decide what to do with the embryos of the undesired gender: freeze, destroy, or donate for other couples or research.
Cost
IVF cycles cost an average of $12,400. PGD adds an additional $3,000 to $6,000-plus to the tab. Check with your medical insurance company — part of the expense may be covered.
Availability
Most fertility clinics that provide PGD don't allow it to be used solely for sex selection. You must have a medical reason such as a family history of genetic diseases or repeat miscarriages, or be over a certain age, usually about 38, to qualify for the procedure.
That said, a few centers allow you to use PGD to choose the sex of your baby even if you don't have a medical reason to do so:
• Genetics and IVF Institute, with facilities in Virginia and Maryland. (To qualify, couples must be married, have at least one child, and desire a child of the opposite gender.)
• The Sher Institutes for Reproductive Medicine, with seven branches nationwide. (Prospective patients are screened on a case-by-case basis, and couples with no children are not excluded from consideration.)
• Reproductive Specialty Center in Newport Beach, California (restricted to couples who have at least one child and desire a child of the opposite gender).
Ericsson
What it is
A technique that aims to separate faster-swimming boy-producing sperm from slower-swimming girl-producing sperm. Sperm of the desired gender are inserted directly into your uterus via artificial insemination (AI).
Effectiveness
Ericsson claims his technique is 78 to 85% effective when it comes to choosing boys and 73 to 75% effective for girl babies.
How it's done
This technique, which has been around since the '70s, attempts to separate boy and girl sperm by pouring a sperm sample on a gluey layer of fluid in a test tube. All the sperm naturally swim down, but the boys tend to swim faster and reach the bottom earlier. Once the fast and slow swimmers are separated, you're inseminated with the sperm that will enable you to conceive the gender you desire.
Pros
• Inexpensive compared to higher-tech methods.
• Noninvasive.
• Relatively safe.
Cons
• There's no guarantee of success. The technique's pioneer, Ronald Ericsson, has published extensively and claims a success rate of approximately 75 to 80 percent. But some fertility doctors dispute this figure and say that it's no higher than 50 percent.
• AI is not as effective as in vitro fertilization (IVF), and it may take many cycles to achieve a pregnancy, depending on your age and fertility.
Cost
Approximately $600 per insemination.
Shettles method
What it is
Timed intercourse on specific days of your cycle.
Effectiveness
Shettles proponents claim the technique is 75 percent effective, but other experts dispute this. Keep in mind that you always have about a 50 percent chance of conceiving the sex you want.
How it's done
The theory is that sperm bearing Y chromosomes (for boys) move faster but don't live as long as sperm that carry X chromosomes (for girls). So if you want a boy, the Shettles method argues, you should have sex as close as possible to ovulation. If you want a girl, you should have sex two to four days before you ovulate.
Pros
• Requires no drugs or invasive medical procedures.
• Free or low cost.
• Relatively safe.
Cons
• You must take your basal body temperature every day to figure out when you're ovulating, or use an ovulation prediction kit.
• There's no guarantee of success.
Availability
Anyone can try it.
Whelan method
Timed intercourse on specific days of your cycle.
Effectiveness
Whelan claims her technique is 68 percent effective for boys and 56 percent effective for girls, but many experts dispute this. Keep in mind that you always have a 50 percent chance of conceiving the sex you want.
How it's done
The Whelan method directly contradicts the Shettles method. The theory here is that biochemical changes that may favor boy-producing sperm occur earlier in a woman's cycle. So if you want a boy, you should have intercourse four to six days before your basal body temperature goes up. If you want a girl you should have sex two to three days before you ovulate.
Pros
• Requires no drugs or invasive medical procedures.
• Free or low cost.
• Safe.
Cons
• You must take your basal body temperature every day to figure out when you're ovulating, or use an ovulation prediction kit.
• There's no guarantee of success.
Availability
Anyone can try it at home.
Sex-selection kits
These at-home kits are based on the Shettles theory. Separate girl and boy kits include a thermometer, ovulation predictor test sticks, vitamins, herbal extracts, and douches that are supposedly gender specific.
Effectiveness
Kit makers claim a 96 percent success rate. But the American Society for Reproductive Medicine tells consumers not to bet on it. Some medical experts go a step further and say the kit maker's claims are without scientific merit.
How it's done
You track your cycle using the thermometer and ovulation predictor test sticks (which you urinate on). Following the Shettles method, you have intercourse two to four days before ovulation if you want a girl and as close as possible to ovulation if you want a boy. The douche is intended to change the vaginal environment to "influence the chances that either an X-carrying sperm or a Y-carrying sperm will be successful in fertilizing the egg." Vitamins and herbal extracts are also included to supposedly boost your odds of getting the gender of your choice.
Pros
• Requires no invasive medical procedures.
• Convenient.
Cons
• The success rate claimed by the makers is questionable.
• Expensive
Low-tech sex selection has not sparked the same controversy, probably because these methods are far from foolproof and the assumption is that couples practicing them are investing less — both financially and emotionally — in their success. But do they work?
These techniques range from Shettles and Whelan to folk wisdom such as making love standing up and eating more meat if you want a boy, and eating lots of chocolate and having sex in the missionary position if you want a girl.
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