The treatment of infertilityThe treatment of infertility is a complex area of Medicine, which is subject to constant evolution and progress. It is also a subject that can be confusing and particularly sensitive to many couples. In this sense, Ferticentro decided to make available online a lot of information on treatments, so that YOU can learn more about the challenges on the great adventure that is the birth of a child.
WHAT IS INFERTILITY?
Whether you have recently discovered that you may have difficulty getting pregnant or you are for some time now struggling to solve your problem, Ferticentro created this guide so that the main questions that arise, from diagnosis to treatment, can be adequately clarified and couples may, on the one hand, make informed decisions and better understand the treatment processes.
Some notions about the mechanisms of human reproduction
To better understand the problem of infertility, we must start by understanding what is fertility, i.e. the ability to conceive a child.
To make it possible to conceive in natural conditions, both members of the couple should be healthy and so there should not be problems in the production of oocytes and sperm. In addition, women should have regular and permeable tubes and an uterus with conditions that allow for the implantation of the embryo.
The time when intercourse occurs is also important. The sperm must find the ovum (or egg) in the tube at the time of ovulation, so that fertilisation can occur.
This is not to mean that sex has to happen at the precise moment that ovulation occurs: there is a period of about two days when conditions are optimal for fertilisation, because after being released from the ovaries, the oocytes can expect 12 to 24 hours to be fertilised. Moreover, the sperm may remain on the female body, capable and active for fertilisation for a period of 12 to 48 hours.
Moreover, we should not forget that in a "normal" situation of a couple that has not fertility problems, the probability of getting pregnant naturally in each menstrual cycle is only around 20-30%.
Hormones are chemical messengers produced by the organism; there are several that are involved in the oocytes and sperm production process. If problems occur with their functioning, difficulties may arise in achieving pregnancy.
At least 20% of women with infertility problems suffer from hormonal disorders, which cause problems in ovulation. The use of ovulation-inducing drugs is one of the solutions commonly used in these clinical situations.
In men, hormonal imbalances can also lead to problems with the production of sperm.
Production of oocytes and sperm
The production of oocytes involves the interaction of several different hormones. The process begins in a part of the brain called the hypothalamus, with the production of the gonadotropin-releasing hormone (GnRH). In turn, this will stimulate the pituitary (a small gland at the base of the brain) to release the follicle-stimulating hormone (FSH). FSH will act on the ovaries and stimulate the development of follicles (where the oocytes are located).
The follicles produce oestrogen, which stimulates the pituitary gland to release another hormone: the LH or luteinising hormone, that promotes follicle rupture and the oocyte release from the ovaries - this mechanism is called ovulation.
The same hormones that control ovulation in women are also responsible for sperm and testosterone production in men.
As it is the case in women, GnRH produced by the hypothalamus in the brain also triggers the release of LH and FSH from the pituitary. In men, FSH stimulates the production of sperm in the testes, while LH stimulates the testes to produce testosterone.
The sperm travels from the testes to the epididymis (which is a coiled tube about 12 meters in length), where they mature. When a couple has sex, sperm travels through the vas deferens, towards the penis. At the time of ejaculation, sperm are propelled from the penis into the vagina of the woman.
Ovulation and menstrual cycle
The number of oocytes that girls are born with can reach 400,000. However, the body is unable to produce more oocytes throughout life. At puberty, the hormones produced will trigger the process of oocyte maturation.
Until menopause, women will release an oocyte per month, more or less on day 14 of the menstrual cycle (which begins on the first day of the period). The average menstrual cycle lasts about 28 days, although this number may vary from woman to woman. The period when the woman is most fertile is usually in the middle of the cycle.
The menstrual cycle
Days 1 to 5 |The endometrium (lining of the womb) is destroyed and eliminated in menstruation.
Days 6 to 14 | The endometrium is gradually rebuilt and, under the influence of oestrogens, it is made sufficiently thick, in order that it is ready to receive and nourish the embryo. Oestrogen stimulates the cervix to produce mucus. This provides a swimming medium and a more favourable environment for sperm.
Days 15-28 | After ovulation, when the oocyte is released from the follicle, the follicle changes into a structure called the corpus luteum. Progressively higher levels of progesterone are produced from the corpus luteum that causes the endometrium to become more watery, thus creating the perfect environment for embryo implantation. If the oocyte is not fertilised, or if it is fertilised but not able to implant in the endometrium, it is eliminated. In this case, the corpus luteum degenerates and progesterone levels fall, which causes the blood vessels in the endometrium to die, the uterine wall to contract and the menstrual cycle starts again.