Dr Victor Khuman
(Contd from yesterday)
Millions of sperms enter the female genital tract following intercourse. Of these only few reach the egg and only one is going to fertilise the egg. There must be a minimum number of sperms in adequate concentration to achieve this. Also only the sperms motile enough will be able to get anywhere near the egg. Moreover no defective sperm will be able to fertilise the egg and in the event it does, it’s unlikely that the pregnancy will continue. Pregnancy is impossible in absence of the female egg. That’s just the case in certain women who fail to ovulate (release eggs). Some of these women may ovulate irregularly, therefore decreasing the chances of conception. Such cases are clubbed as ovulatory dysfunction. Further the number and quality of eggs released depreciates as women ages. After the egg is released from the ovaries, they are picked up and carried towards the uterus by the tubes. The pick up and transport of egg is vital as fertilisation occurs in the tubal lumen and the embryo will further be carried to the uterine cavity. Peritoneal diseases or past surgeries may interfere in these egg pick up and transport. They may also be affected due to tubal diseases or intrinsic problems of the tubes.
Uterine diseases and anomalies may create unfavourable conditions for implantation. The newly formed embryo may fail to implant at all or improperly implant and result in loss in pregnancy of variable duration. Before the sperms enter the uterine cavity, they have to negotiate cervix. Unfavourable cervical conditions hamper sperm vitality and motility.
Initial assessment with thorough medical history and examination of the partners is paramount and may unravel clues to the clinician of the underlying causes of infertility. And many a times lifestyle modifications are advised, particularly weight reduction and smoking cessation. Obesity and overweight have been associated with ovulatory dysfunction and deranged semen parameters. Similarly smoking has strong association. Others like alcohol consumption and caffeine intake have been implicated but to a lesser degree.
Thereafter a basic initial fertility workup must include documentation of ovulation, semen analysis and tubal patency tests. Tubal patency tests being invasive may be deferred in patients where there is very low probability of tubal damage. Semen analysis is an important and appropriate initial step in the evaluation of infertility workup. Male factors contribute up to 35% of infertility cases and therefore warrant evaluation as one of the initial steps in infertility workup. Male causes of infertility are almost always reflected in semen analysis provided there is no other sexual dysfunction (eg. premature ejaculation, impotency, psychological etc.). The most important parameters assessed are sperm concentration, motility and percentage of defective sperms. An abnormal semen analysis may call for further genetic and urological evaluation. Invasive diagnostic tests in the female are best deferred till complete workup of the male partner. In severe male factor infertility, effective options for treatment are limited; hence it determines what additional evaluation needs to be done in the female partner.
Ovulatory dysfunction means a defect in the release of egg from the ovaries. It may be complete where no eggs are released or incomplete where egg release is infrequent (medically termed as anovulation and oligoovulation). Various tests have been devised to detect if and when an ovulation occurs. Without going into the details, naming a few – basal body temperature, serum mid luteal progesterone levels, urinary LH surge, serial transvaginal ultrasonography etc.
The most commonly and readily done tubal patency test is the HSG (hysterosalphingogram). Others include the saline sonohysterography (SSG), and the most recent and most efficient HyCoSy (hysterosalphingo contrast sonography). All these tests has an added edge with the ability to detect uterine factors (eg. Fibroids, polyps, uterine septa, uterine synechiae etc). Hysteroscopy can be employed for direct vision detection and correction of uterine factors in the same sitting. Laparoscopy can also be used for assessment of tubal and peritoneal factors. As with hysteroscopy, laparoscopic corrections of these factors can be done in the same sitting. These are quite safe in experienced hands.
From the wide array of available tests it is the clinician’s prerogative to choose the most appropriate ones in consultation with the couple. It should be kept in mind that necessarily one test may not suffice for complete evaluation. Additional investigations may have to be done subsequently to complete the evaluation and also to determine the optimal treatment. At times, despite thorough and exhaustive search for cause of infertility, no apparent cause surfaces. Such cases are labelled as unexplained infertility.
Having discussed the possible causes of infertility, it is now therefore clear that correction of the particular cause or causes as the case may be, should remove the obstacle in achieving pregnancy. Having detected a cause doesn’t rule out the possibility of other causes. Moreover there may be causes which remain undetected after assessment, the unexplained causes. Therefore correcting one or more defects do not necessarily always treat the couple of infertility. Treatment of an infertile couple should not therefore always focus in correcting all the detected causes. We have to adopt an individualised approach towards evaluation and treatment of an infertile couple.
Tubal and peritoneal problems often need to be surgically addressed. Nowadays laparoscopic approach (key hole surgery) is definitely preferable. Similarly most uterine defects need surgical intervention. Here too hysteroscopic and laparoscopic approach is preferred. For mildly abnormal semen parameters intrauterine insemination (IUI) is a preferred option. In this the washed, selected and prepared sperms are directly deposited into the uterine cavity. This also therefore overcomes any cervical factor if present. IUI is also a preferred treatment for unexplained infertility. In selected cases IUI is coupled with ovarian stimulation for better success. In severely abnormal semen parameters, in vitro fertilisation (IVF) is often the only choice. Better results are expected with intracytoplasmic sperm injection (ICSI) and intracytoplasmic morphologically selected sperm injection (IMSI). ART (assisted reproductive techniques) are the latest techniques employed for fertility treatment, and by definition it involves the direct handling and manipulation of either human gamete (sperm or egg). These techniques include in vitro fertilisation (IVF), intracytoplasmic sperm injection (ICSI), intracytoplasmic morphologically selected sperm injection (IMSI). IVF involves incubating the egg along with prepared sperms, in order to achieve fertilisation outside the uterus in artificial media (test tube baby). In ICSI and IMSI, a single selected sperm is injected directly into the egg using micro instruments under high magnification.
There is a paradigm shift in management of infertility, from detecting specific causes and cause targeted treatment to employing tests and treatments which are most efficient and cost effective. This is due to the surging success of assisted reproductive techniques (ART). For instance following IVF treatment, about 50% of couples with unexplained infertIlity were able to achieve pregnancy.
With all the current available knowledge and technology it is vital for the patients to understand that the benchmark for comparison is 20-30% and not 100%. Having said so with the increasing possibilities of ART coupled with fertility conservation surgeries almost all infertile couples have a good chance at achieving pregnancy. Additionally adopting options like donor sperms, donor eggs, surrogacy etc. even broaden the scope. Timely counselling and evaluation will go a long way in comforting those stressful couples who have been unable to conceive. It is immensely helpful having a proper and complete knowledge and understanding of the situation, and the available treatment options. Let us all embrace this world of new possibilities. (Concluded)
(The writer is Consultant Obstetrics & Gynaecologist, Shija Hospitals, Langol. He can be contacted at [email protected])
Source: The Sangai Express