Some of the common causes of male and female infertility and their treatments are dealt in the sections below:
Infertility is the inability to conceive. But a precise definition is impossible since varying degrees of infertility is seen. Infertility is seen in both males and females, though it is traditional to blame a woman as the cause of infertility if a couple fail to have children. For many couples especially in India, having a child of their own is a very important event in their lives. To be unable to do so causes a lot of anguish and emotional pain to individuals.
1. Female Infertility:
A woman may be infertile due to several causes.
Some important reasons are as follows:
a. Failure to Ovulate:
Failure to ovulate is one common cause of infertility in females. This is because the pituitary or hypothalamus fails to produce the FSH which is required for follicle development or LH required for release of the egg from the ovary. It may also be because the ovaries fail to produce oestrogen or progesterone. Hormonal imbalances may be corrected by administering synthetic hormones to the affected individual.
The most commonly used drug is Clomiphene, a synthetic oestrogen like drug which stimulates ovulation. Tamoxifen is another drug used. These pills are taken orally for five days soon after the menstrual cycle starts. Injection of HCG, which is chemically similar to LH is given at the middle of the cycle to stimulate ovulation. ‘Fertility drugs’ which contains FSH and LH or only FSH is also used.
But these have the danger of multiple egg release and consequently multiple pregnancies. Advance techniques include small implants in the upper arm which releases small amounts of GnRH mimicking the activity of the hypothalamus.
b. Damage to Oviducts:
The fallopian tubes may be blocked or narrowed in some women. This interferes with the movement of the eggs and fertilisation. This can be treated by laser surgery.
c. Damage to Uterus:
In about 5-10% cases, infertility problems are due to a damaged uterus. The uterus is unable to maintain pregnancy, i.e., the fertilised zygote does not get implanted. Sometimes large non-malignant tumours called fibroids or smaller growths known as polyps which grow in the walls of the uterus can cause infertility.
These can be surgically removed. IUCD or PID also causes inflammation in the uterus and cause problems. This can be treated by using antibiotics. Adhesion in the uterus, i.e. sticking of parts of the uterus which occurs as a result of an abortion is another reason for infertility.
d. Damage to the Cervix:
The cervix is the neck of the uterus. The cervix may become damaged because of the abortion or difficult birth. A narrow cervix may interfere with sperm movement.
e. Antibodies to Sperm:
In some rare cases, women may produce antibodies against sperms. These are found in the cervix, uterus and oviducts. These may be treated using immunosuppressant drugs, but IVF is a better method of treatment.
2. Male Infertility:
Infertility in males may be due to the following causes:
a. Azoospermia:
Absence of sperms in the semen is known as azoospermia. This may occur because of lack of sperm production or because of blocked tubes which does not permit the sperms to appear in the semen. Blockage can occur due to an infection or injury.
Failure of the ejaculation mechanism is another possible reason of azoospermia. Failure to produce sperms may result because of injury to the testes or as a result of infection such as mumps virus or due to hormonal reasons (Fig. 3).
b. Oligospermia:
Low sperm count is known as oligospermia. More than 90% males suffer from infertility due to low sperm count. The reasons of oligospermia is summarised in Fig. 3.
c. Abnormal Sperms:
Abnormal sperms may possess two heads, or no tail or may have abnormal shapes (Fig. 4). The reasons are not known and may be because of hormonal malfunctions.
d. Autoimmunity:
In some males, the immune system may attack the sperms and reduce the sperm numbers. Treatment is not usually possible.
e. Impotence and Premature Ejaculation:
The inability to achieve an erection of the penis is known as impotence. Psychological counselling may help in some cases. Premature ejaculation is a condition where the man releases the semen even before penetration into the vagina. This condition is treatable with psychological treatment.
Treatment for Infertility:
Infertility can be treated in a number of ways as explained above. Advanced techniques include in vitro fertilisation, donor insemination and surrogacy.
1. In Vitro Fertilisation (IVF):
In vitro fertilisation or IVF is a technique in which egg cells are fertilised by sperms outside the woman’s body. After fertilisation, the zygote is transferred to the patient. The transfer of the zygote is called ‘Embryo transfer’. The foetus is then allowed to grow in the uterus. The term ‘test tube babies’ are given to zygotes formed thus and grown. In vitro fertilisation is usually performed in shallow containers called petri dishes made of plastic resin or glass.
This technique is used as a treatment for infertility when the normal methods of conception have failed. It is included under a category known as assisted reproductive technology or ART. Embryos can also be formed by in vivo fertilisation i.e., fusion of sperm within the female. These embryos can also be transferred into the body of females who cannot conceive.
The technique of IVF was specifically developed for humans in the United Kingdom by Dr. Patrick Steptoe and Robert Edwards in United Kingdom. The first test tube baby, Louise Brown was born in England on July 25, 1978. Subash Mukhopadhyay was the first physician in India to perform IVF and the test tube baby, Durga was born on July 25 1978. But it was only after 1981 the technique became popular all over the world.
For IVF to be successful, healthy ova, sperm that can fertilise, and a uterus that can maintain pregnancy are required. The woman, from whom the ova are collected, is administered fertility medicines to stimulate multiple follicle development. Endogenous ovulation or ovulation inside the body is blocked by the use of GnRH antagonists. After follicular maturation is achieved, human chorionic gonadotropins or (β-hCG) is injected, which acts as an analogue of the lutenising hormone.
This hormone stimulates ovulation 36 hours after the injection. But the egg is retrieved using a transvaginal technique involving an ultrasound guided needle that pierces the vaginal wall to reach the uterus. From the follicular fluid collected, the ova are identified. The procedure is done in a woman under general anesthesia.
In the laboratory, the identified eggs are stripped of surrounding cells and prepared for fertilisation. In the meantime semen is collected from a donor. The sperm and the egg are incubated together in a culture media for about 18 hours. In a more refined technique a single sperm is injected directly into the egg using the intra cytoplasmic sperm injection or ICSI. This is used for sperm that have difficulty penetrating the egg and when sperm numbers are very low.
The fertilised egg is passed into special growth medium and maintained until the fertilised egg has achieved 6-8 celled stage. Embryos are graded by an embryologist based on the number of cells, evenness of growth and degree of fragmentation. The embryos judged to be the ‘best’ are transferred to the patient’s uterus through a thin, plastic catheter that enters the vagina. Often, several embryos are passed into the uterus to improve chances of implantation and pregnancy.
The patient confirms pregnancy after two weeks. She is administered progesterone, to keep the uterus lining thickened and suitable for implantation. But the major complication of IVF is the risk of multiple births. This is because of the practice of transferring multiple embryos.
The multiple embryos generated, may be frozen. These embryos are placed in liquid nitrogen and can be preserved for a long time. The advantage is that patients who fail to conceive may become pregnant using such embryos without having to go through a full IVF cycle. Alternately, they could use them for another pregnancy.
Ethical, Religious and Legal Issues Raised by IVF:
Several ethical issues have been raised from the time IVF was introduced.
These concerns are as follows:
a. Interference and bypassing of natural method of conception.
b. The idea of creating human life outside in the laboratory is not acceptable to many.
c. Multiple embryos and their uncertain fate are also appalling. The use of embryos for research, manipulation of the embryos are considered unethical.
d. Very expensive and unaffordable to majority of people.
There are several religions which oppose the technique of IVF. In several countries the IVF programmes are subject to regulations that regulate many aspects of IVF practice.
Some are as follows:
a. The number of oocytes that can be fertilised is specified.
b. The number of embryos that can be transferred is also restricted to avoid the complications of multiple births.
c. The use of cryopreservation is not permitted in some countries. In Italy, it is a crime to freeze human embryos or to perform pre-implantation diagnosis.
d. The use of third party reproduction leads to related complications such as the surrogate mother developing a psychological bonding with the developing child and refusal to separate from the child after delivery.
2. Donor Insemination or Artificial Insemination:
Sperms may be obtained from sperm donors. Potential donors are screened for health fertility and genetic diseases. They are also screened for HIV antibodies, hepatitis B which may be transmitted through the semen. They donate their semen, which are then frozen and kept ready. When the woman is ready to ovulate, she visits a clinic, and the frozen sample is gently released into the cervix with the help of a small tube.
The success rate of this technique is very high. However, there are many ethical issues related to this technique. Artificial insemination can be used as a technique to treat impotence premature ejaculation, oligospermia and azoospermia.
3. Surrogacy:
Surrogacy is the phenomenon where the embryos are implanted into the uterus of a woman who may or may not be the donor of the eggs. She ‘rents’ her womb for the development of the embryos. An agreement is reached with the surrogate mother and the couple who desire to have the baby. In case the infertile woman is unable to produce eggs or have a damaged uterus, she may opt for surrogacy.
IVF or GIFT technique may be used to transfer the embryo or gamete into the surrogate mother. Alternatively, the egg of the surrogate mother may be used in which case the sperm may be donated by the male partner. There have been many instances of transfer of wrong embryos and misidentified gametes in some laboratories.