It’s the father who controls his baby’s gender, medical science has proven beyond a doubt. The man contributes both the X and Y chromosomes while the mother’s egg only has the X chromosome, explains gynaecologist and fertility specialist Dr Kelly Loi.
She notes that couples usually want to select the gender of their offspring either because of tradition (preferring the firstborn to be a boy), or because they want to have a balanced family, since most tend to stop at two kids (a girl if they’ve already had a boy and vice versa).
Recalls SmartParents expert Dr Christopher Chong, a gynae at Gleneagles Hospital, “I once had a patient’s friend who flew all the way from South Africa to seek my advice on how to have a boy, since his firstborn was a girl. I gave him some tips and his wife fell pregnant with a boy, soon after his trip!”
To increase your odds of having a boy, only have sex on the day of ovulation.
While some couples will go to any lengths — literally — to sway the gender odds their way, others try to “manipulate” certain lifestyle and natural factors. Here’s what you can do to try and influence your baby-to-be’s gender…
1. Timing intercourse
This popular technique revolves around the Shettles method (which has not been scientifically proven). Named after American biologist and pioneer -vitro fertilisation researcher, Dr Landrum Brewer Shettles, who wrote How To Choose The Sex of Your Baby, it’s based on the theory that the male sperm, which carries the Y chromosome, is lighter, swims faster and has a shorter life span than the “female” sperm, which carries the X chromosome. The latter is heavier, swims slower but has a longer life span, Dr Loi notes.
So, if you’re eager for a girl, have intercourse two or three days prior to ovulation, which gives the Y sperm time to die off, so that the X sperm can fertilise the egg. To increase your odds of having a boy, only have sex on the day of ovulation.
Roberta Ciccone, 36, a stay-at-home mum to Melina, 1, Giovanni, 5, Thomas, 9, and Raquel, 18, and 7 months preggers with her fifth child, swears by this method. After giving birth to her unplanned first child, she used the Shettles method to determine the sequence of the genders of her subsequent children — it has worked each time.
“It’s all about being in-tune with your body and knowing exactly when you’re ovulating,” says Ciccone, who uses a thermometer to track her fertility. She also checks the consistency of her cervical mucus and charts her basal body temperature daily (the body’s lowest temperature at rest).
Your cervical mucus is usually like raw egg white on the day you ovulate, which coincides with a spike in your basal body temperature. You can also track your ovulation with an over-the-counter ovulation predictor kit from a pharmacy.
Dr Loi recommends getting an ultrasound scan at your gynaecologist, which will identify when you are ovulating and the exact time the follicle will rupture and release the egg.
Want a girl? A more acidic cervical mucus favours the X-sperm. Read on!
Your diet, besides impacting your preferred pH level, may also determine the gender of your baby. Dr Loi notes that a study has found that a higher-calorie diet prior to conception is linked to a greater probability of having a boy.
“So, to increase your chances of having a boy, have a healthy, high-calorie diet with regular breakfast and opt for cereal every morning,” she advises. Cereal contains essential vitamins including sodium, potassium and calcium.
When Dr Chong, 50, dad to Nicolette, 14, Dominic, 19, and Beverly, 21, was trying for a boy, both he and his wife followed a pure meat diet — without any sauces or gravies — for a month before trying to conceive. “Our diet was very bland,” he adds. “I still remember I had to wash off my mum’s sedap curry gravy before eating the meat.”
Indeed, research from Maastricht University in the Netherlands also shows that you’re more likely to conceive a girl if your diet is rich in calcium and magnesium — such as oranges, yoghurt, spinach, tofu, almonds, cashews, beans and broccoli.
Also, wave “bye bye” to cured meats, salmon, potatoes and olives as you’ll need to reduce your salt and potassium intake. Conversely, Terri Irwin, wife of the late “Crocodile Hunter”, Steve Irwin, has raved about the success of the salt-and-potassium-rich diet she observed in order to conceive her son, Bob.
3. Body chemistry
A woman’s reproductive tract changes its pH — alternating between acidic and alkaline — environment. Experts believe that acid in the follicular fluid favours X sperm — ideal if you want to conceive a little girl — while an alkaline fluid prefers Y sperm, if you want to increase your chances of having a boy.
You can increase your level of alkalinity by using a lubricating gel when you have intercourse during your fertile period, Dr Chong recommends.
Dr Loi points out, “A more acidic vaginal environment is bad for the male sperm as they’re ‘weaker’ than the ‘female’ sperm and are ‘destroyed’ easily.”
She adds that diet can also modify your pH levels. Eat more red meat and bananas daily for a more alkaline environment, while taking more fruit, vegetables and dairy products like yoghurt and cheese will boost your acid levels.
To make the cervical mucus more acidic, which will “kill” the Y sperm, consume supplements that contain calcium, folic acid, magnesium and vitamin C. Also, if possible, resist the urge to orgasm during sex, since an orgasm produces chemicals that will cause your vaginal environment to become more alkaline.
Husbands trying for a boy should also avoid over-heating their genitals (no hot tubs and laptops on your lap!) and refrain from wearing tight underwear.
“Excessive heating of the genitals is bad for fertility in general and since the Y sperm is not as strong as the X sperm, subjecting them to any kind of challenge is not a good idea,” Dr Chong warns.
“Excessive heating of the genitals is bad for fertility in general.”
How you make love, also makes a difference! Find out why!
4. Sexual position
Couples have been trying to nail this one down for centuries but there really is no lovemaking position that can influence your bub’s gender, according to Dr Loi.
Instead it’s more about the distance of the sperm to the egg. “Since the male sperm is lighter and can swim faster, deeper penetration would theoretically allow it to reach the egg first,” she points out.
Positions with deeper penetration (if you hope for a male baby) include the “Hands-And-Knees”, commonly known as “doggy style”. You get on your hands and knees with your hubs behind, so that he’s that much closer to that all-important baby-making organ, the cervix.
“Since the male sperm is lighter and can swim faster, deeper penetration would theoretically allow it to reach the egg first.”
Another position to try is “Living on the Edge” — lying on the edge of the bed while your husband penetrates you by standing or kneeling, which also allows the penis to be closest to the cervix.
And as boring as it may sound, the missionary position — the classic man-on-top — is believed to be the best as it uses gravity to your advantage, while depositing sperm close to the cervix.
For a girl, attempt shallow penetration, so that the sperm is deposited nearer the entrance of the vagina. This way, the X-sperm will most likely fertilise the egg, since the male sperm is not strong enough to go the distance. Positions that favour shallow penetration include you on top, since you can control the depth of penetration, as well as the standing missionary.
In this one, you stand upright facing one another and you lift a leg up slightly as he bends his knees to facilitate entry.
This article first appeared in Mother & Baby Singapore, March 2014 issue.
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