Making pregnancy happen

Blimey! Pregnancy really is confusing, and it’s not as if women – and the miraculous workings of their bodies – aren’t confusing enough to us already.

These may be your initial ideas when thinking about pregnancy, but just wait until your partner tells you she’s six weeks pregnant, and your mind goes into overdrive, because, technically speaking, the first two weeks of pregnancy are when she’s not actually pregnant.

In fact, the doctors state that pregnancy begins on the first day of your partner’s last normal period. Eh?

However, the foetus doesn’t begin to develop until conception, which occurs around two weeks after the first day of your partner’s last normal period. But, by this time, she is classed as being in the second week of pregnancy.

(Yes, it is completely understandable if your brain is beginning to hurt. If you’re confused, our pregnancy calculator may help you understand.)

Fortunately though, here in the UK, these definitions don’t matter too much. But spare a thought for those in other countries, for example the United States, where there are still seriously polarised political debates around how much choice women should have regarding what they do with their own bodies. In such places definitions of pregnancy really do matter. Now breathe!

Understanding pregnancy – the process

In purely global terms it is probably a good thing that not every act of sexual intercourse ends in pregnancy – try and imagine the size of the world’s population; while in personal terms – if you are one of the lucky couples for whom conception and pregnancy seems to come relatively easily – it is likely you would need a small castle.

In order for it to happen the following must occur:

• 1. Ovulation – the monthly release of a woman’s egg
• 2. Fertilisation – the penetration of sperm into the layers of an egg, thus forming a zygote (new cell). This usually occurs within 24 hours of sexual intercourse.
• 3. Implantation – the zygote turns from a solid ball of cells to become a hollow ball of cells called a blastocyst which then implants into the wall of the uterus before morphing into an embryo. This usually occurs within 14 days of fertilisation.

Once the pregnancy is established the due date will be calculated as 40 weeks from the first day of your partner’s last missed period. This is equal to around nine calendar months and it’s worked out this way because, generally, it’s easier to determine the date of the period, rather than the date of actual fertilisation.

NOW IT MAKES SENSE.

Understanding pregnancy – when is it “safe”?

However, just because ovulation, fertilisation and implantation has occurred does not mean that the pregnancy is “safe”.

The risk of miscarriage in pregnancies under 12 weeks is one in five, while for women with a BMI (body mass index) over 30, there is an increased risk: one in four. While three out of four miscarriages occur during the first trimester.

This means that, once you’ve got your head around the whole pregnancy weeks thing, it may be a good idea to temper your excitement in the early stages and hold off telling too many people – perhaps until the beginning of the second trimester.

And remember, you shouldn’t put too much pressure on yourselves – which of course can be hard if you’ve been trying to get pregnant for a long time. Most cases of miscarriage are in fact completely beyond the control of the parents, with the vast majority attributable to chromosomal abnormalities., maternal illness, hormonal imbalances or problems with the menstrual cycle.

Furthermore, younger women (those between 20 and 39 have only a nine to 20 percent risk of miscarriage, while those who are 40 to 44 have a 40 percent risk rate; for women over 45 this rises to 80 percent.

Trying times

When it comes to trying to get conceive a child, there really is such a thing as too much information.

Trying to time things correctly so that you fill your partner with life-creating semen at around the time she’s ovulating can be an incredibly stressful business. In fact, according to research reported in 2012 in the Journal of Andrology, trying for sex on schedule can have a detrimental effect on the sexual health of men.

The cohort for this study was 400 men and the researchers concluded that “Stress incurred by the thought of obligatory coitus, or compulsory sexual behaviour, causes sexual dysfunction in men facing timed intercourse. It imposes a great deal of stress on men, evoking erectile dysfunction and, in some cases, causing these men to seek extra-marital sex.”

And since you’re trying for a baby together rather than the opposite – seeking the end of your relationship – it is perhaps a good idea to pursue the rather less scientific route of sex, sex and more sex.

Numbers, numbers

Sure, your partner is most likely to get pregnant within 24 hours of ovulation and ovulation usually occurs around 14 days after the first day of her last period, but this does not occur like clockwork and eggs live for 12-24 hours after being released anyway, so there is no certainty.

Instead, try and have sex at least every couple of days; and if your partner is under 35, you have a nine in 10 chance of conceiving a child within 12 months.

Good luck!