Reproductive Health of Class 12
Infertility(L. in–not, fertilis–fruitful) is the failure to conceive when after 1-2 years of regular unprotected sex. The term is not synonym of sterility which means complete inability to produce offspring.
Infertility can best be defined as relative sterility. It is of two types, primary and secondary. Primary infertility is the infertility found in patients who have never conceived. Secondary infertilityis found in patients who had previously conceived. Infertility is caused by defects found in males, females as well as both.
Infertility in Males
Semen of a fertile male is 3-4 ml per ejaculation with a sperm count of over 100 million, mostly motile, having proper fructose content and fluidity which is deposited high in the vagina. Any defect in sperm count, sperm structure, sperm motility or seminal fluid leads to infertility. Low sperm count is called oligospermiawhile near absence of sperms is known as azospermia.Low sperm motility is called asthenozoos permiawhile defective sperm morphology is termed as teratozoospermia.
Cryporchidism or failure of testes to descend into scrotum. It causea azospermia. Absence or blockage of vasa deferentia and vasa efferentia. Loss of ciliary function and sperm motility due to autosomal recessive disorder of kartagener syndrome. Hyperthermia or higher scrotal temperature due to varicocele (varicose veins), hydrocele or filariasis, tight undergarment, thermal undergarment or working in hot environment cause oligospermia or depressed spermatogenesis. Alcoholism inhibits spermatogenesis.
Infertility in Females
A fertile woman is the one who regularly ovulates once every cycle, passes the egg down the reproductive tract which develops conditions for smooth passage of sperms and implantation of fertilised egg. The various causes of infertility in females are as follows. Anovulation(nonovulation) and oligoovulation (deficient ovulation) are caused by deficient functioning of hypothalamo-pituitary complex or secondarily by thyroid and adrenal dysfunction. Inadequate growth and functioning of corpus luteum resulting in reduced progesterone secretion and deficient secretory changes in endometrium. It is called luteal phase defect. It inhibits implantation. Major reason is decrease in FSH or LH level and elevation of prolactin level.
The ovum is not liberated but remains trapped inside the follicle due to hyperprolactinaemia. Fallopian tube may fail to pick up ovum, have impaired motility, loss of cilia and blocked lumen. The defects may be caused by infection or endometriosis. Noncanalisation of uterus.
In vitro fertilisation
(IVF-fertilisationoutside the body in almost similar conditions as that in the body) followed by embryo transfer(ET) is one of such methods. In this method, popularly known as test tube babyprogramme, ova from the wife/donor (female) and sperms from the husband/donor (male) are collected and are induced to from ozgote under simulated conditions in the laboratory. The zygote or early embryos (with upto 8 blastomeres) could then be transferred into the fallopian tube (ZIFT-zygote intra fallopian transfer) and embryos with more than 8 blastomers, into the uterus (IUT-intra uterine transfer), to complete its further development. Embryos formed by in-vivo fertilisation(fusion of gametes within the female) also could be used for such transfer to assist those females who cannot conceive. Transfer of an ovum collected from a donor into the fallopian tube (GIFT-gamete intra fallopian transfer) of another female who cannot produce one, but can provide suitable environment for fertilisation and further development is another method attempted. Intra cytoplasmic sperm injection(ICSI) is another specialised procedure to form an embryo in the laboratory in which a sperm is directly injected into the ovum. Infertility cases either due to inability of the male partner to inseminate the female or due to very low sperm counts in the ejaculates, could be corrected by artificial insemination(AI) technique. In this technique, the semen collected either from the husband or a healthy donor is artificially introduced either into the vagina or into the uterus (IUI-intra-uterine insemination) of the female. Though options are many, all these techniques require extremely high precision handling by specialised professionals and expensive instrumentation. Therefore, these facilities are presently available only in very few centres in the country. Obviously their benefits is affordable to only a limited number of people. Emotional, religious and social factors are also deterrents in the adoption of these methods. Since the ultimate aim of all these procedures isto have children, in India we have so many orphaned and destitute children, who would probably not survive till maturity, unless takes care of. Our laws permit legal adoption and it is as yet, one of the best methods for couples looking for parenthood.