This is the week in which you become pregnant, although the vast majority of women won't actually realise it for a couple of weeks yet!
On average, around two weeks after the start of your menstrual period, you ovulate. During this process, your ovaries release an egg that is ripe for fertilisation by a man’s sperm. This egg, or ova, is the largest cell in your body at about 1/7th of a millimetre in length. Amazingly, the egg has been inside your body for years, safely contained within a tiny sac in the ovaries called a follicle. Each month, hormonal signals prompt a few follicles to prepare for ovulation; one follicle will eventually become larger than the others. Ovulation occurs when the egg breaks out of this follicle and through the wall of the ovary.
Typically, you release one egg a month from one of the two ovaries that are located on either side of your uterus. Once released, the egg is transported down one of the Fallopian tubes. Some women actually feel pain on one side of the belly when ovulation occurs—this is known as mittleschmerz, or "middle pain." For you to conceive, the egg and sperm need to meet as the egg travels down one of your two Fallopian tubes. An estimated 300 million sperm may begin to travel down the tube, but only one is needed to fertilise the egg.
A quick note on pregnancy terminology; the amount of weeks you are pregnant is calcluated from the first day of your most recent period, even though you will probably have actually conceived around two weeks after that.This is because neither you nor your doctor can always be sure of when you conceived, but the first day of your most recent period is an easily measurable starting point of pregnancy.
The amount of weeks you are pregnant is calculated from the first day of your most recent period, even though you will probably have actually conceived around two weeks after that.
Approximately two weeks after conception, you will probably miss your first period, so if you take a positive pregnancy test that day you are termed as being four weeks pregnant. Of course, the date that your pregnancy begins is an educated guess based on the average length of time between menstrual cycles (for most women, about four weeks). All of your scans and midwife appointments will be based on this calculation, although in rare cases, the size of the foetus at the twelve-week scan can result in a slight adjustment of the due date.
If you fall pregnant very quickly after coming off contraception, you may not have experienced regular periods or any periods at all before conception takes place. If that is the case, an ultrasound scan will help determine the baby's due date. One way to roughly calculate this date is to take the first day of your most recent period, add one week, and then add nine months from there. For example, if your period started on 1st January, you first add one week, arriving at 8th January. Then, calculate nine months from 8th January, which gives you a due date of 8th October.