Some people know they're pregnant even before they've missed a period. Others may have irregular cycles and not even think pregnancy is an option. And even more keep having periods throughout their pregnancy. Sort of buying a pregnancy test every time you feel a touch of nausea how else can you know if you're pregnant?
Even before your period is due you may see some changes in breasts. Most women's breasts become tender before their period is due and the veins on them seem to protrude even more, so your breasts can start to resemble a road map. Amazingly, even at this early stage your breasts are changing for milk production. The brownish circles around the nipples (the areolae) become darker and the little bumps on them (the strangely named Montgomery's tubercles) are more prominent.
Often mistaken for a period, implantation bleeding, as it's known, can occur when the fertilised egg arrives in your uterus and embeds itself in your uterine lining. Some women find they lose a small amount of blood around this time, or just before their period. The blood tends to be reddish to begin with, but then quickly turns brownish. It only tends to last a day or two and is not heavy. So if you think you've had an unusually short or light period, it could be that you're pregnant.
Urge to wee
As soon as your progesterone levels rise and the embryo starts to secrete the hormone HCG, the blood supply to your pelvic area increases, which leads to pelvic congestion. This leads to your bladder becoming irritated, and in the process, it tries to expel urine at frequent intervals even in small amounts. Most women therefore experience a desire to wee more often than usual. This can happen as early as one week after conception.
The saliva in your mouth often reflects the chemical content of your blood and with rising hormone levels the taste in your mouth can change. Women have often described their mouth as having a metallic taste. This can make the taste of certain foods such as tea, coffee or your morning bowl of cereal different from before.
Over-sensitive sense of smell
A strange sense of smells, too, can be a sign that baby is on the way. Strong smells, particularly, such as the smell of brewing coffee or frying onions even if you loved them before can suddenly make you feel sick. Perfume can have a similar effect and you may notice the way your perfume smells on your body also changes because of the alterations in your skin's chemistry.
You suddenly start to crave foods you never even thought twice about before. Many women crave tangy foods such as grapefruits, oranges and lemon juice. Other cravings are more peculiar, such as coal and chalk (this is a condition called pica and we don't need to tell you that eating coal is not good for you or the baby, do we?). One theory is that cravings are your body's response to a deficiency in certain minerals and trace elements. If you crave citrus fruits, for example, you could be deficient in vitamin C although we don't know this for sure yet.
Feeling overwhelmingly tired throughout the day as if you could just lie on your office floor and sleep to sleep forever, partly due to the high levels of progesterone in your body, which has a sedative effect. During early pregnancy, your metabolism speeds up in order to support your developing embryo and your vital organs, which have to cope with an enormously increased amount of work. And the tiredness is probably worse if it's your second or third baby, when you're less likely to have a chance to rest.
You feel sick
Nausea is often worse in the morning mainly because you have an empty stomach and your blood sugar has dropped, but some women feel sick all day! Pregnancy sickness has been associated with poorer diets, infrequent meals and stress associated with the pregnancy. The hormone HCG (human chorionic gonadotrophin) is probably the most likely cause of pregnancy sickness.
But at least there's a positive side to nausea and vomiting in pregnancy it's a sign that hormone levels in your bloodstream are high enough to ensure that the pregnancy is well established (although don't worry if this doesn't apply to you, as some women are lucky enough to sail through their pregnancies without feeling sick).
To be sure...
Of course one easy way of finding out you are pregnant is to do a pregnancy test. You can buy a test kit from your local pharmacy or supermarket. Pregnancy test kits are 99 per cent accurate (a positive test is almost definitely correct; a negative result is less reliable you may have to wait a week and start again).