Below is a generic advise. Please be warned that for more specific or accurate advise, more information is needed on the background of the mother.

Information such as age, social status, brief medical/gynecological history, ethnicity, height/weight/body size and the pregnancy term now would be helpful to provide a better understanding and better advise.

Nevertheless, normally the traditional vitamin for pregnant women would be Obimin (Reg TM) multivitamin, Pramilet (Reg TM) or the generic equivalents. Most prenatal/antenatal vitamin contains (shown is for obimin):

The best way to ensure that you and baby get the nutrients needed is by eating a healthy, well-balanced diet consisting of vegetables, fruits, fish and grains. In some instances (eg morning sickness) you may require multivitamins specially designed for pregnant women. Antenatal vitamins should contain more folic acid, iron and calcium as compared to the general multivitamins available.

FOLIC ACID: Beans and green leafy vegetables are rich in folic acid. If you're a healthy woman who eats a balanced diet and has no specific risk factors, not all experts agree that you need to take a prenatal supplement, so you should talk with your practitioner about what's right for you. But everyone does agree that you need to take 400 micrograms (mcg) of folic acid daily for the first trimester and ideally 3 months or at least a month before you start trying to get pregnant. (In fact, since half of all pregnancies are unplanned, the U.S. Public Health Service recommends that ALL women of childbearing age take 400 mcg of folic acid a day.)

And the recommended amount goes up to 600 mcg a day once you're pregnant. That's because research has shown that folic acid can reduce the risk of neural tube defects in your baby by up to 70 percent. If you do take an antenatal supplement, is likely to contain between 600 and 1,000 mcg of folic acid. If you don't take antenatal supplement, make sure you take a separate folic acid supplement instead. If you've previously had a baby with neural tube defects (spina bifida), you will need to take 4,000 mcg, or 4 mg, of this vitamin daily at least one month before conception. (stand alone folic acid supplements comes as 5mg tablets)

IRON: Antenatal supplement contains enough iron, which is important to make the extra blood required to support your growing baby. since most women don't get enough in their diet to meet their body's increased needs during pregnancy. The amount recommended when you're pregnant is 27 mg of iron per day, 50 percent more than you need when you're not. (Most antenatal supplements contain between 27 and 60 mg.)

That's because your body makes a lot more blood when you're pregnant to support your growing baby, and as a result, the iron stores in your blood can get spread pretty thin. To avoid getting iron-deficiency anemia during pregnancy, most women need to take a supplement. The amount of iron in antenatal supplement is normally enough for most women. Sometimes, high doses of the iron can make nausea and constipation worse. (Supplements that contain no more than the recommended amount of 27 mg probably won't cause you any problems, though.) If you are already anemic before pregnancy, it's a good idea to start taking an iron supplement now. Women with iron-deficiency anemia are usually advised to take between 60 and 120 mg of iron each day in addition to an antenatal supplement.

CALCIUM: You need 1500mg calcium daily during pregnancy. Calcium is rich in milk products, green leafy vegetables, salmon, tofu and sardines. Calcium is important for building strong bones and teeth.

Vitamin C has been much spoken about for its benefits in pregnancy. You will do just fine with the amount of vitamin C in a glass of orange juice (about 85mg). The need increases to 120mg when breast feeding. Vitamin C, also known as ascorbic acid, is essential for tissue repair, wound and bone healing, and healthy skin. Vitamin C also helps your body fight infection. Both you and your baby need this vitamin daily - it's the cementing agent that holds new cells together, and it helps your body absorb iron. Try to include a vitamin C-rich food with every meal to get the most iron out of the other foods you eat.

It is also important to note that too much vitamin A can be harmful for the baby. Just as important is to know that no more than the recommended amounts of vitamin A is taken as that can be harmful to your baby if you take too much. This is the reason why antenatal supplements contain vitamin A in the form of beta-carotene, a nutrient that you get from fruits and vegetables that converts to vitamin A in the body. Vitamin A derived from animal products is harmful, and can cause birth defects when taken in high doses before conception or during pregnancy.

Finally look for antenatal supplements that provide 100% RDA. Do not take more than 1 tablet daily. Women with medical condition such as diabetes or anemia should consult their doctor for any other special supplement needed.

Since a few years ago, Fish Oil (Salmon, Tuna, Shark, Mixed), which containes DHA (decahexanoic acid) and EPA (eicopentanoic acid) has been hypothesized to be of benefit in the development of the fetus especially the brain. Much of the human brain is composed of DHA. However, studies recommending Fish oils or their specific components are insufficient to make a credible recommendation at this point. If you do decide to take them, just be sure that they are molecularly distilled for that extra peace of mind over their manufacturing quality, as you will be at ease knowing that the mother and child are safe from lead and mercuric (and arsenic) contamination/poisoning.

FYI, most Fish oil undergo molecular distillation as part of their extraction and purification process. In fact, the hype over molecular distillation is generally a marketing hype. Personally, i think 1000mg Fish oil is fine as an add-on supplement to the more important ones above. Achtung: Taking DHA rich food or supplements does not beget Einstein or genius babies.

Never forget that good healthy nutritious diet and plenty of rest is crucial during pregnancy as it could determine the development of the child and the ability for the mother to carry the baby in her womb. An often neglected fact is that the baby usually takes what is necessary, leaving the mommy deficient in certain vitamins and minerals, such as iron and calcium.

Take care and happy parenting : )