Cambridge Temperature Concepts DuoFertility, Быстрый старт и Руководство пользователя

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6
Understanding your menstrual cycle and ovulation
The menstrual cycle is the process during which your body prepares for pregnancy.
As you approach ovulation each month, your uterus becomes more welcoming to
sperm, allowing them to survive longer and swim to the egg, which increases your
chances of getting pregnant.
Each menstrual cycle begins on the first day of your period and ends on the day
before your next period. The menstrual cycle is composed of three different phases
and lasts 28 days on average, in which case ovulation is expected to occur between
day 11 and day 16. However, it is not unusual to have cycles which are as short as 20
days or as long as 60 days.
Ovulation is a key event in the menstrual cycle. During the follicular phase, one of
the follicles which are contained by the ovaries reaches complete maturity and one
egg/ovule is released. This is triggered by a surge in luteinising hormone (LH).
After ovulation, the released egg travels along the Fallopian tubes, where
fertilisation by sperm can occur. The ruptured follicle left behind after ovulation
forms the corpus luteum which secretes progesterone, the hormone responsible for
the rise in body basal temperature (BBT) that signals ovulation. It also suppresses
the ripening of further follicles, induces closing of the cervix and the thickening of
cervical mucus. The corpus luteum then disappears with the onset of menstruation.
The lifespan of the released egg is only 24-48 hours. Therefore, for fertilisation to
occur, sperm must either be already present in the female reproductive tract, or
intercourse must take place soon after ovulation. Sperm can survive for 3 to 5 days
in the vaginal environment if the right kind of cervical mucus is present. This is
why the few days before and after ovulation are when you are most likely to get
pregnant, with the peak time being the day of ovulation.
When you ovulate, the vaginal environment becomes more welcoming and friendly
to sperm, making this the most fertile time of your cycle and therefore the best time
to try for a baby. Cervical mucus becomes less acidic and more elastic and the cervix
moves from a low, firm, dry and closed position to being soft, high and open. All
these changes facilitate the passage of sperm to the uterus and the Fallopian tubes.
This is therefore the best time of the month to try for a baby.