is a spontaneous cyclic (monthly) physiological
shedding of internal lining of uterine cavity
(endometrium) due to invisible interplay of female
hormones. In simple terms, it is a regular monthly
bleeding which a woman experiences.The first menstruation
occurs usually at the age of 12 – 15 years.It
is also called as ‘menarche’. For the past couple
of decades, the age of menarche is gradually declining
with improvement of nutritious and environmental
the menstruation starts, it continues cyclically
at an interval of 22 – 35 days with a mean
of 28 days.
it stops during pregnancy and lactation.
it ceases between the ages of 45 – 50 years
when menopause sets in.
duration of menstruation (menses) is about
4 – 5 days and the amount of blood loss is
estimated to be 20 – 80 ml with an average
of 50 ml.
menstrual discharge consists of mainly a dark
altered blood, mucus, vaginal epithelial cell
fragments of endometrium, prostaglandin, enzymes
at the midcycle, a mature egg is released
(ovulation). If it gets fertilised, the menses
ceases. Thus the absence of menstruation suggests
that pregnancy has occurred. Link to signs
and symptoms of pregnancy in confirming pregnancy
Ovulation is a process by which a mature
egg (mature Graffian follicle after secondary
oocyte is releases) is released from the surface
of ovary to be available for fertilisation viz.
only one mature egg is released in each ovarian
relation to the menstrual period, the event
occurs 14 days prior to the expected date
of menses. However, menstruation can occur
is very high during mid cycle, for the same
remains suspended during pregnancy and lactation.
ovulation, the mature egg (ovum) is picked
up into the fallopian tube and undergoes further
maturation, if fertilization has occurred
or degeneration if it does not get fertilized.
ovulation, the ruptured follicle undergoes
a change called corpus luteum formation, which
secretes hormone progesterone.
is unrelated to ovulation and no ovulation
during menstrual cycle is quite common during
young age (adolescence), following childbirth
and in women approaching menopause.
is a process of meeting (after mating) of
the sperm with a mature egg.
begins with sperm egg collision and ends with
a formation of life called zygote (single
mononucleated cell mass)
ovum immediately following ovulation is picked
up by the fimbrial end of the fallopian tube
and is rapidly transported to the ampullary
part of the tube.
of hundreds of millions of sperms deposited
in the vagina after intercourse, only thousand
specialised sperms enter the uterine tube
while only 300 – 500 reach the egg.
of this elite community, only one lucky member
is allowed to get into the mature egg.
sperm either contains (22 X) or (22 Y) pattern
of chromosomes while the egg contains 22 X
sex of the child is determined by the pattern
of the sex chromosome supplied by the sperm.
the sperm contains (22 X) a girl child (46 XX)
is formed, if it contains (22 Y) a boy child is formed. .
fertile period is period around ovulation, during
which if relations are kept, the chances of pregnancy
are high. In order to improve the chances of pregnancy,
it is important to understand how to calculate
the fertile period.
of a fertile period:
- Mark the day 1
of your menses on a calendar. Do this for next
6 -8 cycles.
- Note the length
of the longest cycle and shortest cycle.
- Subtract 18 from
the length of the shortest cycle. Say you get
a figure "Y"
- Subtract 11 from
the length of the longest cycle. Say you get
a figure "Y".
- So the period you obtain between "X" and "Y"
is the fertile period.
- Your shortest cycle is of 28 days, and the
longest cycle is of 30 days.
- As you know, the
ovulation occurs approximately 14+ or -2 days
before the next menstrual period. So the highest
fertility period is around ovulation time i.e.
- The life span
of the mature egg is approximately 48 hours
(2 days) while the life span of the sperm is
approximately 72 hours (3 days). So even when
the relations are kept on day 10 or 11 of the
menstrual cycle success can be achieved.