WOMAN ENOUGH: A JOURNEY ACROSS THE BASIS OF THE FEMALE REPRODUCTIVE SYSTEM

Few days ago we discussed on several basic principles that govern the male reproductive system in humans. Well, we were able to establish the fact that for an individual to be considered man enough, certain principles must be satisfied. Actually I didn't plan on having a continuation for that POST, but a comment from @greenrun greatly aroused my curiosity and I somehow felt the urge of writing on the very basis of womanhood. This promises to be intriguing and at the same time I'm optimistic that we'll reach some level of enlightenment.

Womanhood: The unanswered questions about this phenomenon

Unfortunately, the concept of womanhood is one that'll always leave series of questions behind in the mind of a rational being. Why am I saying this?. Actually, decades ago I grew up to witness a particular prejudice against the married women. In situations where the woman is not able to produce children, she'll be considered barren and not woman enough. In actuality, I've seen cases where such a woman is sidelined by the family and even in the society regardless of the fact that the man (her husband) might even be the culprit. Now, this was the setting of a typical African society. As a matter of fact, to an extent this weird ideology is still not eradicated till today.

From the above description, you'll agree with me that while Merriam Webster dictionary defines womanhood ‘as the state or condition of being an adult woman and no longer a girl’, other individuals view it in a whole different perspective. For such individuals, womanhood is more than growing and hitting puberty, it's more about the healthy state of the reproductive system. Well, I really don't know which of these ideas really explain the exact meaning of womanhood, but that notwithstanding, we'll be looking at the basic principles that govern the female reproductive system in humans.

Lets start with the basis...

Like I said in my previous post, the reproductive system of both the male and female humans comprises of the internal and external parts. But unlike the male reproductive system, the parts that make up the female reproductive system are mostly internal. The only external genital happens to be the vulva; that is the fold of skin surrounding the opening and a small rod-like structure (clitoris) that hangs just above the opening. Also, there's nothing like urinogenital organ(s) in females since their urinary and reproductive passages are separate and open separately to the exterior unlike in males where the urethra directly passes through the Penis.

Now, starting from the interior, the female reproductive system comprises of two ovaries lying suspended in the abdominal cavity just below the kidney. From there we have funnel-shaped openings that are positioned quite close to each of the two ovaries. Well, it might interest you to know that these funnel-shape openings are the entrances of narrow spiraling tube-like structures called the Fallopian tubes or oviducts. Furthermore, each of the ovaries is being led into a single pear-shaped uterus or womb. Finally, from the uterus there's a ring of muscles (known as the cervix) that connects the uterus to the vagina which then leads to the exterior.

Talking about female humans not having urinogenital organ(s), I guess I should probably explain in a more simple terms why it's so. Funnily enough, while handling this topic with my High School students, one of them (male) asked me a question that almost made me laugh so hard. He said, "sir, if the hymen is what covers the entrance of the vagina, then why are virgins able to pee?". The question plus the expression on his face alone depicted the level of his curiosity. But like I said earlier, the external genital of the female human is the vulva. It's worthy of note that from the exterior we literally have two openings that are linked to the vulva. The first is the urethral opening while the other is the vaginal opening which is covered by a fold of connective tissue called the hymen. In an ascending manner, the urethral opening is connected to the bladder while the vaginal opening is linked to the uterus. These openings perform the functions of urination and reproduction respectively. With that being said, it's quite obvious that the presence of hymen on the entrance of the vagina can never hinder urination.

Events that take place in different parts that make up the female reproductive system in humans

Just like the males, the female gonads (ovaries) also produce gametes and sex hormones. The name of the female gamete is the egg or ovum, while that of the 4 sex hormones are the follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen, and progesterone. As we move ahead we'll get to discuss more on the roles of each of these hormones. But before that, I'd love to pinpoint the fact that potential male gametes (sperm cells) are not present in the testes at birth. However, for the females, all the potential egg cells which are about two hundred thousand (200,000) are already present in the ovaries at birth. Well, at this stage they are mostly referred to as primary oocytes.

That notwithstanding, for the males, the good thing is that once they start producing sperms at puberty, they don't stop until old age. Well, this isn't the case for the females. Eggs maturation begins at puberty and stops at menopause. The little shocking knowledge I'm sure you'd love to hear is that out of the 200,000 egg cells that were already present at birth, several research studies assert that the range of egg cells that mature during a female's active reproductive life (i.e from puberty to menopause) is only about 400 to 500. For the males, even though they start producing their gametes at puberty, they can still produce as much as 300 million sperms daily. That's a huge achievement I guess.

So at this point it's pertinent to say that since the ovaries contain all the egg cells or primary oocytes at birth, once the female hits puberty series of events will start occurring leading to the maturation of the egg. First and foremost, when a primary oocyte begins to develop in the ovary, it is surrounded by actively dividing granular cells. Experts believe that the main function of the granular cells is to nourish the primary oocyte since it's capable of receiving nutrients. Now, both the primary oocyte and granular cells collectively form a whole structure called a follicle. As a matter of fact, it's believed that the follicle-stimulating hormone (FSH) is what triggers the development of this follicle. Interestingly, if you have an idea about hormonal interaction then you'll understand better how the action or concentration of one hormone can stimulate or inhibit the release of another hormone. Indeed you'll appreciate this insight as we move ahead.

Since FSH initiates the development of follicle, the developing follicle begins to secrete another hormone called estrogen. In actuality, the level of the estrogen increases as the follicle matures. During the maturation of the follicle, it becomes filled with fluid and the oocyte inside is pushed to one side. So, with the kind of pressure built inside the mature follicle, this results in the splitting of the ovarian lining. Now, immediately the ovarian lining splits, there's always a release of an egg or ovum. On that note, we can say that the process whereby the primary oocytes develop, mature and is released as an ovum is known as ovulation. Actually, it takes 14 days for one of the ovaries to complete this process. Yet, there might be cases where both ovaries are stimulated to undergo ovulation due to certain factors. Now, this is the kind of situation that gives rise to fraternal twins. Later you can read more about the factors that encourages fraternal twin conception in this Post I made months ago on the unanswered questions about fraternal twin conception. For now let us go back to the subject matter at hand. Whether egg maturation is taking place in one of the ovaries or both, an important hormone that will cause its release from the ovary is the luteinizing hormone. This hormone is released as a result of the increase in estrogen blood level.

Oftentimes, more than one follicle develops at the initial stage in the ovary. Nevertheless, only one usually mature to produce an ovum while the rest break down. The mature follicle has a name and it's called Graafian follicle. As a matter of fact, the role of the Graafian follicle doesn't just end after it splits up to release the ovum. Besides, the luteinizing hormone helps it (Graafian follicle) develop into a solid yellow body known as corpus luteum responsible for secreting the hormone progesterone and a small amount of estrogen. As we continue, we'll get to see the need for progesterone. Meanwhile, once the ovum is released, it is wafted into the oviduct(s). Out of curiosity someone might want to know what could cause the ovum to move lightly through the air into the oviduct(s). The simple answered is, from our High school knowledge of biology, we were told that the opening of the oviduct is fringed with muscular finger-like structures bearing cilia. Actually, the truth is that these cilia beat continuously thereby creating a gentle current that wafts the released ovum into the oviduct.

From my earlier description of the oviducts, you already know they are narrow spiraling tubes. All the same, it doesn't end there. Oviducts have muscular walls that are lined with mucus-secreting cells. Immediately the ovum enters the oviduct, it is moved passively to the uterus through the contractions of the muscular walls of the oviduct. Indeed, the journey of the ovum to the uterus is really an interesting one. According to studies, it takes about 3 days before the ovum can reach the uterus after its being released by the ovary. During the early part of this journey, the ovum can become fertilized if there's presence of potential sperm cell. In essence what I'm trying to say is that the oviduct is the exact location where fertilization occurs. Luckily enough, if this happens, the newly formed embryo is implanted in the uterus where it stays and develops. At the same time, it might interest you to know that what aids the implantation of the embryo is the fact that the uterus or womb has a mucous membrane lining called endometrium. This endometrium is what actually receives the fertilized ovum.

Earlier on I promised to highlight the function(s) of the hormone progesterone. The truth is that progesterone and a small amount of estrogen secreted by corpus luteum is what maintains and enrich the endometrium. Also, when the ovum is fertilized, progesterone inhibits FSH thereby stopping it from triggering the development of new follicles. On the other hand, if there's no potential sperm to fertilize the ovum, the ovum dies. Correspondingly, since there's no fertilization, implantation of the ovum will also not be possible. Now, why implantation of the embryo is impossible is because the corpus luteum shrivels when fertilization doesn't occur. And as you already know, if corpus luteum should shrivel, progesterone and estrogen will no longer be produced. And in the absence of progesterone, two things must definitely happen:

• The thick tissue of the endometrium will breakdown and it's discharged from the body with a certain amount of blood through the vaginal opening (menstrual flow).
• FSH will not be inhibited and follicles will begin to develop again (start of sexual cycle)

Final thoughts

I’d love to conclude it this way… in a normal and healthy condition, the concept of the female reproductive system is a very interesting one. In cases where the ovum is fertilized, an offspring is expected. If the ovum isn't fertilized, the biological system sees it as an opportunity for cleaning the internal environment while starting the sexual cycle all over again. In both aspects, the female human has absolutely nothing to lose. Like I said in my previous article on male reproductive system; reproductive health for the females is also very important and it deserves all the attention you can possibly give. It doesn't really matter if you are the wealthiest woman in the world; honestly, if your reproductive system is not in a good shape or condition, then you're definitely miles away from being woman enough. I sincerely hope you've learned a thing or two from this article. Thanks for doing this with me. Till next time!

To read more about this topic, check out these REFERENCES

Female reproductive system from wikipedia.org

Ramalingam, S. (2011). Modern Biology, 6th Edition. Nigeria: Africana First Publishers Plc, pp. 452-454.

Image sources

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