Raw fish

Expectant mothers are also often told "no sushi" by friendly or nosy onlookers. In fact, in Japan, most women eat sushi and sashimi throughout their pregnancies. What most Western doctors caution against are bacteria and mercury intake. While it is true that all raw fish may contain some bacteria, filter feeders (oysters, clams, mussels, scallops, some types of shrimps) can be assumed to be a little bit more dangerous than the rest and should not be eaten raw during pregnancy.

The other issue is mercury: foetuses are more vulnerable to mercury poisoning than grown adults and an excessive amount of mercury can impair the nervous system of a growing baby. However, it is worth nothing that only the largest fish (tuna, swordfish, shark) are usually the ones that contain the highest amount of mercury, simply because they have lived longer in mercury-contaminated waters. It is safe for pregnant women to eat smaller fish such as sardines, saury and mackerel, whether they are raw or cooked, and eating small fish rather than those perched on top of the food chain is also better for the environment. As a general rule of thumb, silver-skinned sushi (such as the ones pictured below) are usually from smaller fish.

Finally, studies have shown that it can be more dangerous for women to avoid raw fish completely while pregnant: the reason being that for a lot of women, raw fish is almost their only source of vitamin D. Vitamin D is a key source for the absorption of calcium and bone development; by cutting out raw fish entirely, women can risk suffering dangerously low levels of vitamin D, which ironically could damage their unborn babies even more than trace amounts of mercury.

Raw eggs

Raw eggs may contain salmonella, which is why most people avoid them during pregnancy. While most women will remember not to eat a soft-boiled egg for breakfast, it is also important to remember that raw eggs come in many, often hidden, forms. Lots of sauces are made from raw eggs including hollandaise and mayonnaise; while a number of desserts can also contain raw egg whites, such as tiramisu and mousses. Additionally, a lot of restaurants now serve "sous vide eggs", which are eggs slow-cooked at about 63 degrees Celsius, which is not a high enough temperature to kill salmonella. (Egg dishes need to be cooked to about 71 degrees before the bacteria is killed off.)

Read our guest blogger from St. George's post on his pursuit of the perfect sous-vide egg here.

However, eggs are one of the most nutritious things we can eat, and - as long as thoroughly cooked – are a fantastic source of protein, zinc and vitamins A, B12 and D for pregnant women.

Chinese food

Traditionally, there are some foods eaten in Cantonese households when a woman is pregnant which are seen as especially nourishing such as sea cucumber, fish maw, bird's nest and hasma (the fatty tissue found near the fallopian tubes of frogs). What these items have in common are that they are all high in protein and low in fat, making them ideal for providing much-needed protein for growing foetuses.

It is also a popular Chinese belief that during pregnancy, most women suffer a yin deficiency as a lot of yin flows to the foetus, along with blood. As yin is associated with cold, women suffering from a yin deficiency will result in excessive internal heat, which manifests itself in thirst, excessive sweating and constipation. To counteract this, women are recommended to eat "cold" foods such as white gourd, coconut, beans, pears, lotus seeds, spinach, sesame, white fungus, and lily roots during their pregnancy. Foods that are high in yang such as excessively salty or spicy food, red meat especially mutton, fried food and crabs are believed to cause miscarriages or deficiencies in newborns.

For those that are too lazy to cook at home or can't be bothered remembering all the myriad rules governing what you should or should not eat, T'ang Court at The Langham in Tsim Sha Tsui features a year-round pregnancy menu which features separate menus suitable for women in their first, second and third trimesters, as well as one dedicated to women that had just given birth. All the menus feature six courses and are priced at HK$550. Remember to order a day in advance to ensure availability. (Tel: +852 2132-7898)