Ovulation and Fertilization

Ovulation and fertilization are the most important components of women fertility. If healthy woman during monthly menstrual cycle produces normal mature egg, she becomes a best candidate for fertilization and pregnancy. But ovulation is only one component – there are several other factors necessary for pregnancy including healthy active sperm, healthy fallopian tubes, absence of infection in women reproductive tract and some other factors.

Each woman should know everything about ovulation and fertilization process for two main reasons – one, because it is very important for becoming pregnant and second, it is important for save in-time family planning and contraception.

OVULATION

Ovulation is an important phase of your menstrual cycle. Ovulation is the release of the egg from the mature ovarian follicle – it is usually happening roughly 14 days before next menstrual period. Few days before and after ovulation are most fertile days for women – sometimes these days called “fertile window”. During other days of the menstrual cycle women are less fertile or not fertile.

Women hormones are responsible not only for ovulation but also for body preparations for pregnancy or next menstrual bleeding (if egg was not fertilized). Usually ovulation directly follows the LH surge (pick of Luteinizing Hormone) in the middle of menstrual cycle. Once mature egg is released, it can survive about 24 hours – only during these 24 hours egg can be fertilized. This is why it is important to know that in most ideal conditions (ideal vaginal/uterine environments, fertile eggs, strong sperm health, absence of infection, etc) sperm may be able to survive about 6-7 days in women reproductive tract – it means women could have an extended “fertile window” before ovulation. Some scientists suggest that on average sperm can survive just 2-3 days. In all cases with each passing day more and more sperm die and the odds of conceiving diminish.

So if you have classical 28 day menstrual cycle and if you are trying to conceive a baby – best days are 9-15 days of your menstrual cycle.

Important to remember – women are fertile for about 24–48 hours around the time of ovulation (before and after ovulation).

Having often sex during ovulation will not necessarily increase your chances of getting pregnant. Having sex everyday may reduce the sperm count. Often ejaculation can reduce the sperm activity and quality. The recommended regime is intercourse every second day during ovulation period. Best days for getting pregnant fast are 9-11-13-15-17. Remember –  sperm can live in woman body up to 72 hours after intercourse.

If you are not planning to have a baby – most secure days are first 5 days and last 5 days of your menstrual cycle (period of menstrual period and 5-7 days before expected next period).

NATURAL FERTILIZATION

In order for the woman to get pregnant, one of her mature healthy eggs need to combine with a man’s sperm – this is actually so called “fertilization”.

Following ovulation, the released egg (ovum) is picked up by the fimbria of the Fallopian tube. It remains in the ampulla portion of the tube (in average during 18-24 hours). If you had unprotected sexual contact, then about 100-300 millions of sperm could move to Fallopian tubes. On their way from vagina to fallopian tubes, thousands of spermatozoids would disappear because of several obstacles (microbes, immune system, wrong movements, etc.) and only several hundred of the healthiest spermatozoids will be awaiting the appearance of the solitary ovum in Fallopian tubes.

In most cases the healthy sperm can stay alive (“wait”) in Fallopian tube during about 48 hours. The most active one sperm penetrates the protective field known as the zona pellucida (egg). In order for fertilization to take place, sperm cells must find a keyhole (or receptor) to unlock the zona pellucida, gain entrance, and burrow their way to the oocyte (genetic core of ovum). Only one sperm will connect with the oocyte, precipitating genetic combination – signaling that fertilization has just taken place. With fertilization, the ovum becomes the zygote or embryo and now passes through complex phases of cell division and differentiation.

If fertilization does not occur, the ovum disintegrates and is destroyed by the tube – this is the signal sent for next menstrual period.

ARTIFICIAL FERTILIZATION – In Vitro Fertilization

If couple is healthy, natural fertilization happening easily and happy parents can plan having baby any time they want. But unfortunately there are millions of infertile couples who are trying to conceive without success.

Modern medical technologies can insure artificial fertilization if natural fertilization is not possible for several reasons including absence of fallopian tubes, absence of ovulation or abnormal ovulation, weak sperm or absence of spermatozoids, unexplained infertility, etc.

Artificial fertilization means fertilization in vitro (out of woman body, in medical tubes). In Vitro Fertilization is commonly called “IVF” – it the process of fertilization by manually combining an egg and sperm in a laboratory dish. It is a procedure which ends up with so called “tube babies”. When the IVF procedure is successful, the process is combined with a procedure known as embryo transfer, which is used to physically place the embryo in the uterus.

During In Vitro Fertilization (IVF) medical professionals imitate the biological natural fertilization steps which are:

• Monitor and stimulate the development of healthy egg(s) in the ovaries;
• Collect the eggs;
• Secure the sperm;
• Combine the eggs and sperm together in the laboratory and provide the appropriate environment for fertilization and early embryo growth;
• Transfer embryos into the uterus.

You can discover more about InVitro Fertilization and about Assisted Reproductive Technologies in following pages.