Testis: is the male gonad (organ of generation) – It produces millions of sperms – the male germ cell (also called the male gamete). The testis is an oval shaped organ, lodged in a bag of wrinkled skin called scrotal sac which is seen hanging between the upper thighs. The testis is present one on each side of the midline in the scrotum. Being outside the abdomen, the temperature of the scrotum is 20 to 30 lesser than the normal body temperature; this is ideal for growth and maturation of sperms. Sperms are produced inside tiny coiled tubes called seminiferous tubules. These sperms mix with other secretions of the male reproductive system (seminal vesicle and prostate) to form a fluid called the semen. Besides sperms, the testis produces a hormone called testosterone (the male sex hormone). This hormone is released directly into the blood. Testosterone maintains typical male sexual characteristics like deep voice, largemanly muscles, body and facial hair, and it also stimulates the production of sperm.
Epididymis: Sperms are collected by the epididymis, a comma shaped organ above the testis. The sperms undergo functional maturation here.
The female reproductive system is largely restricted to the pelvic cavity with the exception of the breast. It consists of:
There exists two cycles in the female reproductive system – ovarian and uterine.
By about the 14the day LH from the pituitary stimulates the ovary to produce progesterone. Ostrogen production continues.
It is also around this time (mid-cycle) that the ovary releases one ovum. Although several follicles ripen in both ovaries, only one reaches completion (from only one of the ovaries) and releases the ovum. LH causes a slight rise in basal body temperature on day 2 after ovulation and therefore can be a rough indicator that ovulation has occurred. This is measured by a domestic thermometer and the reading is taken from the mouth early in the morning just at wake up.
Hence the ovarian cycle can be divided into a pre-ovulatory or follicular phase and a post ovulatory or luteal phase.
During its course through the fallopian tube, there is a good chance that the ovum can be fertilised by the sperm. Hence forconception to occur, the couple must time their sexual intercourse to coincide with this period i.e. 1 day prior and 5 days after the day 14 of the menstrual period (day 14 also included). This is calculated considering that the sperms can survive for upto 5 days in the female genital tract. Hence a good timing may be an important strategy for achieving conception.
In the event of a successful sexual intercourse, several sperms of the male will swim through the uterus and enter the fallopian tube. Here one of the sperms will fuse with (fertilises) the ovum. This results in the conceptus (baby ) and the sequence of events is the pregnancy.
However, if the fertilization does not occur, the uterus will shed its endometrium within the next 2 weeks; this results in the menstrual flow. After ovulation, the left over cells of the ovarian follicle convert into a structure called corpus luteum. This has a short life span during which it secretes oestrogen and progesterone. These hormones get the uterus ready for the fertilized egg to be implanted soon. By about 24th – 26th day of the cycle, the hormones are produced in very low levels. The uterus reacts in the next two days by shedding off its inner lining (endometrium). This is referred to as monthly bleeding or menses. As the hormone levels fall, the female undergoes a stage called premenstrual tension. This is reflected as anxiety, irritability, headache, mood swings, pelvic discomfort, muscle cramps, bloating, constipation, swelling and tenderness of the breasts.
Menses is an indication that the uterine cycle is running actively and pregnancy has not occurred. Cessation of menstrual periodsin a sexually active female is a strong indication of pregnancy and tests may be undertaken to confirm this. In the event of pregnancy, the uterine endometrium will develop further to receive the fertilised egg and provide nutrition and support to the growing baby.
The uterine cycle closely parallels the ovarian cycle and is in fact driven by the ovarian hormones. In a 28 day menstrual cycle, let us consider the first day of bleeding (menses) as day 1 of the cycle. Menses is the shedding of the inner lining of the womb and is called the endometrium. It is noticed by the female as bloody discharge for about 5 days. The next 9 days are characterised by proliferation of glands and blood vessels. Hence, this phase of 14 days (5 plus 9) is called the proliferative phase – it parallels the pre-ovulatory phase of the ovarian cycle. It is chiefly controlled by the estrogen produced by the ovary.
From day 15 to day 28 (secretary phase) the uterus parallels the luteal phase of the ovarian cycle and is characterised by secretion from the glands; there is also an increase in blood supply. The endometrium becomes rich in glycogen. This phase is designed by nature to keep the uterus ready for receiving the baby. In the event of pregnancy, the phase continues into full-fledged pregnancy. In the absence of pregnancy, the uterus is slowly removed from the influence of the progesterone and sheds its endometrium at the end of the cycle (end of 28th day). Thereafter the next cycle commences. Hence, the female reproductive system is designed to release one ovum per cycle, enable fertilization thereafter and subsequently to host the developing baby in the uterus. Cycles are programmed to repeat in the absence of pregnancy. The male reproductive system, on the other hand continuously produces sperms in numbers counted in millions. The male is ready to impregnate a female with sperms almost anytime (except when he has released sperms less than 24 hours earlier).
The only way to achieve pregnancy in the normal process is through frequent unprotected sexual union with your partner. By this we mean actual penetration of the male penis into the female vagina, followed by release of semen into her.
What happens during sexual union: The friction caused by moving his penis in and out of her vagina will cause both the partners to get increasingly excited until eventually he ejaculates (or ‘comes’) and releases a sticky white substance called semen. Semen contains millions of sperms – the male germ cells. These sperms swim up the woman’s vagina, into her uterus (womb) and then into her fallopian tubes where they may join with the tiny egg that she releases from one of her ovaries every month. If this ‘union’ (also known as fertilisation or conception) occurs, then she will become pregnant.
Ovulation window: The most important point to be noted is that sex must take place around the time the female partner is ovulating. During this time, the sperms will swim through her reproductive tract and reach the ovum where fertilization takes place (union of the ovum and sperm; see figure). Ovulation occurs approximately on the 14th day after the previous mensus (counted from the first day of the previous mensus). Since this date can be variable, it is best to have frequent sex during the period when the female partner is not menstruating. In general two to three days of sex per week is recommended. More frequent the sexual union, higher the chances of achieving pregnancy. Once fertilization has taken place the ovum does not allow any other sperm to enter it. Hence subsequent sex on the following days will have no dangerous effect on the developing embryo. However it is better to be gentle in lovemaking if a couple is planning for pregnancy.
Importance of conception:
Events following conception in the female:
For the male partner:
Natural sexual activity:
Stimulated cycle sexual activity: As a part of the management of infertility, it may be necessary to use certain medicines to mimic or actually direct an ovarian cycle in a normal pattern. This is called stimulated cycle sexual activity. Ovulation inducing drugs are given to the female partner. Sex between the partners is advised appropriately depending on the timing of ovulation.
Most couples of typical child bearing age are able to achieve a pregnancy within one year if they have intercourse twice per week or more often without using any birth control. Some couples experience difficulty in conceiving even after one year of trying. When pregnancy is this slow to occur, the condition is termed as infertility. Infertility can occur because of problems with the male partner or the female partner or both. A few cases could also be an unexplained infertility.
If a couple are trying to get pregnant for more than one year (or six months if they are 35 years or older) and have not been successful, a series of tests will be needed to identify the cause of infertility. The ovary, uterus and the fallopian tubes of the female as well as the sperm of the corresponding male partner, and possible blood tests in both to check for hormonal problems may be necessary.
Male factor infertility refers to the failure of a couple to achieve conception due to problems specifically related to the man’s sperm, seminal fluid, or male reproductive organs. Similarly, if the reason for failure to conceive lies with the woman, it is referred to as female factor infertility.
Infertility and its causes may be different for each couple. During the last decade, medical science has made great strides in the ability to diagnose and treat infertility. Roughly two out of three of couples who seek medical intervention are able to give birth successfully and become happy parents.
Check list for a probable conception:
A normal female reproductive anatomy.
Normal functioning ovarian and urterine cycle with regular monthly release of a normal good ovum. Good coordination from the pituitary gland and hypothalamus.
No disease or blockage in the transport pathway of the ovum ( normal patent fallopian tube).
Normal urterine endometrium where the fetus will be finally lodged.
Age at conception: preferably below 30.
Normal family history with no major genetic problems.