Natural ovulation cycles
Every month from puberty to menopause, an egg is released from a follicle within one of your ovaries. In natural ovulation, each month your ovary starts to grow several follicles, one of which becomes dominant.
Two hormones are responsible for the development of follicles within your ovaries:
- Follicle Stimulating Hormone (FSH) and
- Luteinising Hormone (LH)
The cells in the follicles also produce oestrogen and progesterone. Your hormone levels will rise and fall at different stages of your monthly cycle.
If the egg meets a sperm somewhere in your fallopian tube, fertilisation may occur. At that moment, the egg becomes a zygote and then, once cell division begins, an embryo travels down the fallopian tube to your uterus, where it will hopefully, implant in the endometrium. This typically happens about seven days after ovulation.
Your Pregnancy Window
When you get your period, the ovary starts to develop a dominant follicle, which is a small sac containing the egg.
Ovulation occurs after about 14 days on average, when the egg matures and is released. The egg can survive for about 8 hours in the fallopian tube, waiting for fertilisation by a sperm, which ideally should be waiting for the egg.
Your pregnancy window is the fertile time leading up to ovulation and fertilisation.
Once you know your pregnancy window, ensure you have sexual intercourse about 2 days before ovulation so sperm is already present in the fallopian tubes. Sperm can survive for 2 to 3 days, waiting for the egg to be released.
We don’t recommend using temperature charting as it only indicates ovulation after it has happened, and you need to have intercourse before ovulation. If you are concerned about your menstruation cycle, we can carry out tests to see what is happening.
How do I know when I ovulate?
Every woman is different, and your cycle may also vary month to month. The time from the start of your period to ovulation could be as little as 8 days, or as much as 18 days. The time from ovulation to menstruation is more consistent from 11 to 17 days though the average is 14 days.
To work out when you ovulate, subtract 14 days from the number of days in your cycle. So if your cycle is usually 28 days, you can expect to ovulate on day 14. This is true for the average woman but unhelpful for many others so bodily symptoms may be of benefit, such as fertile mucus change or increased libido.
You may also notice other symptoms of ovulation around that time, such as fertile mucus or an increased libido.
What causes infertility?
Infertility has been historically defined as a couple not conceiving after 12 months of regular unprotected sexual intercourse. Nowadays with so many wome being older when hoping to conceive, six months is a more workable definition.
The woman's age aside, infertility can be caused by problems within the female reproductive system, such as ovulation failure, tubal disease or endometriosis (about 40% of cases), or with sperm (again, about 40% of cases). In about a third of cases there are both male and female factors causing problems.
> Understanding your menstrual cycle
> Conceiving after using contraception
> Female causes of infertility
> Pregnancy predictor
