Menstrual Cycle and Fertility

You may confuse your period as your menstrual cycle, but it is more than that. Your menstrual cycle comprises of various changes that your body goes through every month, as it prepares the uterus for pregnancy by releasing an egg from the ovary. The menstrual cycle comprises of two phases – the follicular phase and the luteal phase.

The first day of your cycle is the day you get your period. It can go on for 3 to 6 days. The follicular phase is from the second to the fourteenth day. During this period, the follicles on the ovary are active and the endometrium starts to grow. The cervical mucus also becomes thin during this period. Ovulation occurs on day 14. It is calculated by counting 14 days backwards, from the first day of your next period. Ovulation occurs when due to a rise in the level of oestrogen, the luteinizing hormone is released and follicles ovulate. This leads to the release of an egg. Ovulation timing may not be precise, it can occur anytime between the 12th and 14th day.

After the egg is released, the follicle becomes the corpus luteum and the luteal phase begins. Progesterone is released and the uterine lining is created for implantation of the fertilised egg. If the egg doesn’t fertilise and implantation doesn’t happen, the level of progesterone and oestrogen falls and the endometrium is shed. This is when you get your period.

The most fertile period of a woman’s menstrual cycle is the time around ovulation. It is not possible to pinpoint the exact day of ovulation, but the 10th to 16th day can be considered. If a woman’s cycle is of 28 days, then she would be fertile on the 14th day of her menstrual cycle, but for most women, the cycles are shorter or longer.

The fertile period can be calculated by charting your menstrual cycles each month. Select your shortest cycle and subtract 18 from it, for your first potential fertile day, and from your longest cycle, subtract 11 for your last probable fertile day. To narrow it down further, you can chart your basal body temperature, that is your body temperature in the morning before you get out of bed. When this temperature rises slightly (by a degree), it suggests that ovulation has occurred 12 to 24 hours before. Another way of marking your most fertile period is by observing changes in the cervical mucus. When ovulation occurs, the cervical mucus becomes wet and stretch with an almost transparent appearance.

The best chance of conceiving is by having sexual intercourse during this fertile period, three days leading to and including ovulation.