Pregnancy: What Happens and How

For many of us, having children is easily one of the most significant and important part of our lives. Once you and your partner have decided to become pregnant, you will probably go on to look for information about every aspect of pregnancy from the very beginning right through to the end. This is an important step because there are many health considerations that you may not have paid much heed to before, but are key to a healthy and fulfilling pregnancy. Below is a straightforward and informative description of how pregnancy works and what to expect biologically.

Getting pregnant

The first step for any pregnancy is sexual intercourse, a process by which sex cells from a male and female come into contact. This contact is what starts the whole business off as a baby begins through the union of male sex cells, called the sperm, and the female sex cell, the egg. Sex cells all carry genetic material, which is the blueprint of life dictating our many features big and small. One half of your baby’s genetic material comes from Dad, while the other half comes from Mum, which explains why you might see Dad’s nose and Mum’s chin on your new born baby girl or boy, or in some cases, both!


Male ejaculate is composed of millions of sperm, all competing to gain access to the one female egg. Eventually one of these will get through and penetrate the outer surface of the egg, achieving what is called fertilisation, which is just a term for the biological union of male and female sex cells. The resulting fertilised cell is called a zygote, and it is this little cell which begins to divide and grow to form, in time, a fully grown human baby. Normally one baby is the consequence of this whole process, but in some cases either two separate eggs are fertilised, forming non-identical twins, or a fertilised egg splits and carries on as two separate identical twins. This doesn’t happen very often, but there’s always a chance of it happening which explains how and why you might get twins.

The next stage

If you are experiencing any of the tell-tale signs of pregnancy, like morning sickness and a disruption of your periods, then you should go ahead and obtain a pregnancy test available from any chemist’s and many supermarkets. These are easy to use and largely accurate, all you have to do is urinate on the designated part of the stick provided and wait for a colour change (typically to blue) that indicates pregnancy. These aren’t 100%, so you should do another test to confirm or arrange to see your GP to make absolutely certain. Once you’re sure, then congratulations! You are pregnant and can expect to give birth to your son or daughter 9 months, or about 28 weeks, from conception.

Your pregnancy is medically split into three distinct phases, called trimesters, each about 3 months in length (although this tends to vary and will be individual to you). Each trimester is about 3 months long and your doctor, usually a specialist in obstetrician will be able to provide expert advice as to the right health measures at each stage. You can be confident in that you will be well supported by your GP and specialist, can there is a wealth of information on the internet (like this!) which can answer your questions.

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