When it happens - Usually early in the first trimester, it is usually the first thing an expectant mum notices about her pregnant body. 

Healthy sign - The rising levels of estrogen and progesterone, both of which are needed for a healthy pregnancy can also make your breasts enlarged and sore. But, it is a sure sign your little one is thriving!

When it happens - Usually in the first trimester and it can last right up until the last trimester unfortunately for some women. For most, it easy off towards the end of the first trimester.

Healthy sign - No one knows the exact reason behind the morning sickness, but it is a sure sign of a healthy pregnancy. Experts believe a rapid rise in the human chorionic gonadotropin hormone (hCG) could be to blame -- and that increase in hCG is needed for a pregnancy to progress.

In fact, those frequent trips to the bathroom could be beneficial for you and your baby. New research suggests that moms-to-be who experience morning sickness are less likely to miscarry or deliver prematurely.

It's also been suggested that nausea and vomiting help prevent pregnant women from eating foods that could harm their baby in the first trimester when organ development takes place. The idea is that meats and many vegetables may have toxins or parasites that could hurt the fetus. When experiencing morning sickness a mum is usually forced to eat bland food prevents the potential exposure of toxins.

That said, don't worry if you're not experiencing morning sickness. Many women don't and go on to deliver perfectly healthy babies.

When it happens - Around 4 to 6 weeks pregnant

Healthy sign - Seeing blood in your underwear can make any mum-to-be anxious, no matter how small the spotting. But, if it happens early in the pregnancy, around 10 to 14 days after conception-it could implantation bleeding. This early indicator of pregnancy is when the fertilized egg attaches itself to the lining of the uterus, which can result in light pink or brown discharge. It's okay if you don't experience spotting, though not every woman does (and some mistakenly attribute the bleeding to their period).

When it happens -The entire pregnancy

Healthy sign - During pregnancy, most women see an increase in watery, clear, odourless discharge. Another side effect of an increase in estrogen. Apart from being a sign of a healthy pregnancy, the extra discharge is thought to help cleanse the vagina and even prevent infections from entering your womb.