It has been dubbed the boob jab - an injection that boosts the size of a woman's breasts within the space of a lunch hour. The latest cosmetic craze does not require surgery and can be completed in less than half an hour with no recovery period. It involves a gel-like filler called Macrolane to enlarge or firm up breasts under the guidance of fully-conscious patients.

But the effects are not permanent, lasting from 18 - 24 months before a top-up is required. Neither is it cheap, at around $5000 to $7000. Yet fans say it is relatively painless and a less extreme alternative to breast implants, allowing them to subtly target specific areas without necessarily increasing cup size nor telling their friends.

The Singapore based pioneer of the Macrolane Firma breast enhancement technique, Dr Woffles Wu, is travelling to Australia next month to teach plastic surgeons how to administer the procedure. It is expected to be available in Australia by early next year, although Dr Wu already performs In-transit breast augmentations for eager Australian patients on stopover in Singapore.

This literally is the first lunch hour breast augmentation. says Dr Wu. It literally allows patients to come in, walk out, wear a bra and go back to work without feeling any unpleasant symptoms.

I do it with the patient sitting up holding a mirror and I get her to control where she gets the Macrolane injected. Surgeons use a local anesthetic for the procedure, which is also approved in Europe and the US. Macrolane is made up of hyaluronic acid, a naturally occurring gooey molecule similar to the cosmetic filler Restylane.

Unlike silicone, which is commonly used in breast implants, it can be broken down by the body. Patients can avoid scarring and target problem areas such as flat nipples by opting for enhancement instead of implants, according to Dr Wu.

It used to be all about size, so when I started this I thought I was going to have women coming in saying: make them bigger. he said.

But we get patients coming in who have really small boobs who will say: I would just like a little but I still want to be a B-cup.

I will say: 'Don't you want to be bigger?' But they say: 'No, I just want to be fuller like I was before pregnancy' or 'I play sport and I don't want them getting in my way'.

British dental hygienist Lucy Mitchell decided to have Macrolane breast enhancement to fill out her post-pregnancy breasts after years of using Wonder Bras and Chicken Fillet padding. After increasing from a 34A to a 34B cup size last month, she is reportedly delighted with her beautifully rounded and full breasts. However the cost of regular top-ups means she is now considering breast implants as a long term solution.

1) Boob jabs cost about $5000, depending on how much filler is used.
2) Breast implants cost about $12,000
3) The procedure takes 30 minutes under local anesthetic and has no recovery period.
4) Patients can direct their surgeons to specific areas. There is no permanent scarring.
5) A jab last 18 months to 2 years. Patient have top ups as required.
6) Macrolane is made of non-animal hyaluronic acid, a gel-like filler that is eventually absorbed and broken down by the body