When are you most fertile?

 Ovulation usually occurs about 14 days after your period, but if your cycle is longer or shorter than 28 days your fertile period will be later or earlier accordingly.

During your monthly cycle the body goes through various changes to prepare for conception.

The cycle is mostly controlled by the hormones oestrogen, progesterone, follicle –stimulating hormone  (FSH), and luteinizing hormone (LH).  A peak in LH triggers ovulation.

Your body temperature drops and then rises just before ovulation. You are fertile for one day before the temperature drops, as well as for one day after it remains elevated.

Your cervical secretions go through a cycle of changes too as you approach your fertile period the secretions increase and become clearer, stretchy, and slippery ready to receive sperm.

At ovulation one follicle ruptures, releases its egg, then becomes a structure called the corpus luteum. This produces the hormone progesterone, which is essential for the development of an embryo. If the egg is not fertilized, however, the corupus luteum shrinks.

After ovulation, under the influence of oestrogen and progesterone, the endometrium (lining of the uterus) becomes thick and spongy to receive the egg. If the egg isn’t fertilized, the corpus dies and the endometrium is shed at your next menstrual period.

Here is an approximate fertility guide based on a 28-day cycle.  There can be a slight chance of conception throughout your cycle as mans sperm can live inside a woman for as long seven days.

Day 1-5
Development            Menstrual period
Hormone levels        Normal, FSH slight increase    
Body temperature    Normal
Cervical Secretions  Period (usually no secretions)

Day 6-9
Development             Relatively infertile phase
Hormone levels         Normal, Oestrogen begins to rise, FSH dips back
Body temperature     Normal    
Cervical Secretions   Dry, no secretions

Day 10 - 12
Development            Relatively Fertile
Hormone levels        Oestrogen rises steadily
Body temperature     Begins to drop
Cervical Secretions   Moist, sticky, white, cloudy


Day 13-15
Development             FERTILE
Hormone levels         Strong rise in LH, FSH
Body temperature     Drops and rises sharply
Cervical Secretions  Wet, slippery, stretchy, clear
Follicle/ Egg               Peak fertile period- the egg is released from the ovary.


Day 16-19
Development                Relatively Fertile
Hormone levels            LH, FSH drops back to normal, oestrogen levels out,
                                      Progesterone rises
Body temperature        Remains slightly higher than normal
Cervical Secretions     Moist, sticky, white, cloudy

Day 20-28

Development                 Infertile phase
Hormone levels             Oestrogen and Progesterone stay fairly high, eventually drop.
Body temperature         Steadily drops back to normal
Cervical Secretions       Dry, few secretions

Taken from the book: Conception, pregnancy and birth, by Miriam Stoppard. Click here for more information and to purchase.

Start a discussion :: Print this article ::