Hello and welcome to this lesson from the unit hormones and human reproduction.

The title of today's lesson is using hormones to treat infertility.

So we're going to be looking at people who are finding it difficult to conceive, to have a baby, and how that they can be given hormones in order to promote their ability to conceive.

My name's Mrs. Barnard and I'm going to be taking you through today's lesson.

So by the end of today's lesson, you should be able to describe the use of hormones to treat some types of infertility in humans.

And we've got some key words for today's lesson.

And our key words are infertility, menstrual cycle, IVF, FSH, and embryo.

If you'd like to write those down, then you can pause the video now, but otherwise we'll be going through them as we go through today's lesson.

So our lesson today is in three parts.

We have infertility, so we're gonna look at defining that.

Then IVF, which is one of the fertility treatments that can be used.

And finally evaluating IVF.

So let's get started with the first part of today's lesson, which is infertility.

So fertility is the ability to produce offspring.

So we see this in the menstrual cycle where we've got the egg that's being matured, it's been ovulated, and then the uterus lining is thickened and the menstrual cycle takes place.

The fertility of a human female is controlled by this menstrual cycle, and hormones will control the cycle to ensure that an egg is available each month for fertilisation.

And that the uterus lining is prepared for implantation.

So we've got the three stages, egg maturing, ovulation, and then the uterus lining being thickened.

If the egg is fertilised in the fallopian tube, it will then be able to move down into the uterus and implant into the uterus lining.

So just a reminder of the menstrual cycle and the hormones that are involved.

So in days nought to five, remember we can start the cycle anywhere, but we tend to start it on the first day of the period or menstruation.

So from days nought to five, progesterone levels decrease and this causes menstruation to take place.

From day six to 14 FSH, which is released from the pituitary gland, causes a follicle to mature and then the egg inside that follicle will eventually be released.

Oestrogen is also released from the ovary caused by FSH.

What the oestrogen does is it has two jobs.

It causes the thickening of the uterus.

So for that to start, and it causes LH to be secreted from the pituitary gland.

On day 14, about day 14, LH causes ovulation.

So that's the egg, that mature follicle to release that egg and then progesterone is released, which maintains the womb lining just in case that egg is fertilised in the fallopian tubes, it will then need to implant.

And the progesterone will continue to maintain this uterus lining.

And it prevents the secretion of FSH and LH, so that we don't have any more eggs matured or released until we are ready with the uterus lining being prepared again.

And then we're back to the start with progesterone levels falling and menstruation starting again.

So infertility is when a couple are finding it difficult to conceive or become pregnant despite having regular sexual intercourse.

And this can be due to not enough or low levels of specific reproductive hormones.

And we know we're all different.

So the levels of hormones will vary between different individuals, but these different levels of hormones can affect the development of sperm cells in males, but it can also affect the normal processes of the menstrual cycle.

So some women do not produce enough FSH, so therefore their eggs are not maturing in that monthly cycle.

And we can see in this graph that FSH in normal levels in a menstrual cycle, that as those FHS levels rise, that follicle begins to mature.

And to prepare that egg to be released in ovulation.

Hormones can be given to women who are infertile in order to promote them to have a natural pregnancy.

So some women who may have low numbers of eggs maturing, or no eggs released at ovulation, they can be given two hormones.

They can be given FSH to cause the eggs to mature, and they can be given LH to stimulate ovulation.

And again, on this graph we can show that the FSH there will allow those eggs to mature inside the follicle.

And then we've got LH, which causes ovulation.

A lack of FSH being produced by the pituitary gland can be treated with a drug called clomifene.

And clomifene is a drug which promotes the production and release of FSH and LH.

So rather than actually giving people FSH and LH, it's a drug that you can give people which will increase their natural production of FSH and LH.

And as we can see in this image, those are the two hormones that are really needed for that maturation of the follicle so that egg is ready to be released and for ovulation.

So FSH causing the follicle to mature, with the egg inside that follicle there, and then LH causing the egg to be released on ovulation.

So time for a quick check.

So choose the hormones which can be given to a woman who is finding it difficult to conceive.

So we've got progesterone, LH, oestrogen, and FSH.

So make your choice and then we'll come back, and we'll see if you've got it right.

Okay, so the correct answer is LH and FSH.

So if you've got those right then well done.

And here is your practise task for this lesson part.

So Laura and Jacob are discussing infertility, and Jacob says, "Infertility is where a couple cannot get pregnant." And Laura says, "Infertility can be caused by a lack of hormones." Now Laura and Jacob are both correct.

So could you explain the definition of infertility, and its possible causes by adding more detail to both of their statements.

So pause the video while you do that.

And when you come back I can give you some feedback.

Okay, then let's see how you got on with that one then.

So Jacob says, "Infertility is where a couple cannot get pregnant." So we can add some more detail to that.

And we can say, "This is over a long period of time.

For example, 12 months, despite regular sexual intercourse, infertility can affect the male or the female in the relationship." And Laura says, "infertility is caused by a lack of hormones." So you can add detail to that by saying, "It may be caused in females due to a lack of FSH and LH being released from the pituitory gland.

This can lead to a lack of eggs maturing or being released during ovulation." So if you've got something with some detailing that's similar to that, then you've got the answer right? And well done.

So it time to move on to the second part of today's lesson, which is IVF.

So increasing the chance of natural pregnancy with hormones is an example of something called ART, which is assisted reproductive technology.

Sometimes that might just be referred to as fertility treatment.

So this might be the first stage that a couple go through.

So they'll first try having hormones or drugs that stimulate hormones to be released in the body naturally so that their pregnancy can continue naturally.

But another example of an assisted reproductive technology is IVF, and IVF stands for in-vitro fertilisation.

And this procedure can be used if the male sperm is low quality or the female's fallopian tube, sometimes called oviducts, are blocked.

So the first stage in IVF is to give the female the hormones FSH and LH.

And the reason that they give the female those hormones is because they want lots of eggs to mature in the ovaries.

They want lots of follicles to mature and have those eggs ready for ovulation.

And for those eggs to be released because then they can be harvested.

So in a normal cycle, only one egg would be matured per cycle.

But when IVF is being used, want lots of eggs to be matured at the same time.

These eggs are then collected from the mother and then they are fertilised by the sperm in a dish in the laboratory.

Now fertilisation can take place via incubation.

So if the sperm are a good quality, which means that they can move very easily, then often if you just incubate the eggs in the sperm together in the Petri dish, the normal processes that would occur in the fallopian tube take place.

But sometimes if the sperm are not very mobile, they may be, like in this picture, actually be injected into the egg.

So the development of microscope has made this technique possible 'cause you can see that this is an image taken down a microscope and how closely you can see the egg in order to be able to push the sperm into the egg using that syringe.

So the fertilised eggs, the zygote, are then stimulated to divide to form an embryo.

So once the embryo are a few cells, so before they're differentiated, when they're all the same type of cell, they're either frozen, which means that development is stalled, and then they are implanted into the mother's uterus.

So you can see in this image here, so the eggs are harvested, you can see at the top there.

And so they use big aspirating needle that goes through the skin through to the female's ovaries in order to take those eggs out.

Then they'll be fertilised, either through injecting the sperm, or through incubation.

And then they'll be allowed to grow into an embryo.

So lots of embryos will be formed, and then those embryos are either frozen or they are implanted into the mother's uterus.

One, maybe two, are implanted into the mother's uterus.

Ah, we've said that here.

One or two embryos will be implanted into the mother's uterus and the embryo may then develop into a foetus.

Now, not always.

So let's have a quick check.

So I'd like you to place these stages in the correct order to show the process of IVF.

So we've got embryos implanted into the mother's uterus.

We've got a female being given FSH and LH hormones, we've got fertilised eggs stimulated to divide into an embryo, and we've got eggs out extracted and incubated with sperm.

So pause the video while you put these into the correct order and then we'll come back, and we'll see if you've got it right.

Okay, let's see how we've gone with this one then.

So number one in this process is that female is given FSH and LH hormones.

Number two is that eggs are extracted and then incubated with sperm.

Number three, the fertilised eggs are then stimulated to divide into an embryo.

And then number four, embryos are implanted into the mother's uterus.

So if you've got those right, then well done.

So time for a practise task now.

So what I'd like you to do is take this diagram and label the stages of IVF onto this diagram.

Remember to include as many keywords as possible, and descriptions of each stage in the process.

So pause the video while you do that.

And then we'll come back and we'll see how you've got on.

Okay, so you may label it in a different way to me, but these are the stages that I have labelled on the diagram.

And I've gone round it and numbered it in order.

So you might want to do that if you haven't numbered it as well.

So first of all, FSH and LH are given to stimulate the eggs to mature.

And then number two, the mature eggs are removed from the ovary.

And then number three, mature eggs are incubated, or injected with sperm.

And then number four, the fertilised eggs develop into embryos.

And then number five, the embryos are then implanted into the female uterus.

So if you've got all those right, well done.

If not, maybe correct your method just to make sure that you've got the whole procedure there.

So it's time for us to move on to the third part of today's lesson, which is evaluating IVF.

Remember that's looking at the pros and the cons.

So when an individual or a couple decide to have fertility treatments such as IVF, they must evaluate the process.

Evaluate means to consider the benefits as well as the drawbacks, which might include also risks.

The benefit in this case is that an individual couple will have the opportunity to have their own child, although this is not guaranteed.

So in the UK, so this is different rules in different countries.

So in the UK, the NHS set the rules for who could receive funded IVF, which means get it for free.

All others have to pay privately, which is expensive.

About 5,000 per cycle.

Now in terms of some of the rules, some of the rules might be to do with the person's BMI, the person's age.

Sometimes it's what area that they live in.

So different NHS areas will have different rules for whether IVF is paid for or not.

So there's quite a lot to think about.

People can pay for IVF privately though, and that wouldn't have the same rules, but it is expensive.

The percentage chance of conceiving by IVF decreases with age.

So in 2019, the percentage of IVF treatments that resulted in a live birth was 32%.

So that shows you a third of people that have an IVF cycle would have a baby.

Now that's for women under 35.

So that falls to 4% for women over 44.

So you can see by this graph the age has a really big impact on whether IVF is successful or not once you get over the age of 35.

There is a good success rate in younger women, and the procedure has been used safely since 1978.

Embryos can be screened for serious genetic diseases before implantation.

So people who may have genetic diseases in their family, and they may consider having IVF, so that they can have their embryo screened.

Unused eggs and embryos can be frozen.

And they can be used in the future by the couple, or they can be donated to other couples, or they can be donated to research.

So apart from the success rate, there are some other drawbacks to IVF.

So IVF can lead to multiple births.

So if more than one embryo is inserted into the uterus.

Now this happens a lot less than it had when this procedure first started, because when this procedure first started being used, lots of embryos were implanted because it wasn't as successful.

And therefore there were more examples of multiple births, but not as many embryos are implanted now so that this is not the case as much these days.

This can make the pregnancy and the birth more high risk, which increases the chance of harm to the mother and the foetus.

The hormones taken to mature those eggs can have side effects so that FSH when it matures, the eggs can have side effects that give you hot flushes or severe headaches.

It can also lead to too many eggs developing.

It is a stressful procedure and it might not end in success and therefore it can be very emotionally draining.

And if it's been expensive, if you've had to pay for it and then it's not successful even more so.

Some people are also concerned about the ethical implications of IVF.

So ethical issues are whether people think it's right or wrong.

One of the ethical issues is the more embryos are produced than can actually be used.

And some people consider embryos to be new lives, and therefore would view their destruction as unethical.

So they would believe that this procedure shouldn't take place.

Some people are against IVF because the issue of who owns these embryos and whether they can be used in research before eventually being destroyed, is contentious.

As embryos are often viewed as the beginning of life and therefore people would have ethical issues with them being destroyed.

The use of genetic testing, so having your embryos screened for diseases is also controversial, as there is potential it could be misused.

And in choosing, for example, in choosing the characteristics of the offspring IE designer babies, although this is not actually allowed, it's just something that people are concerned about the potential that it could happen.

So let's do a quick check.

So choose what are the drawbacks of IVF from this list below.

Pause the video and then we'll see if you've got it right.

Okay, so the correct answers are, the drawbacks of IVF.

There are ethical concerns with making excess embryos.

There are also side effects of hormone drugs, and the success rate is under 40%.

So let's have a look at the practise test.

So this is an in evaluate practise task.

So Izzy is writing a letter to an infertile couple.

She wants to include an explanation of the IVF procedure, a description of the benefits, and a description and an explanation of the drawbacks.

So what I would like you to do for your task is to write a letter to this couple detailing the IVF, and to evaluate the process in order to help them make a decision.

So this will take you a little bit of time, so pause while you do that and then we'll come back.

And I can give you some feedback using a model answer.

Okay, I hope you all got the opportunity to have a go at writing a letter.

So let's look at model answer.

So here we go.

The IVF procedure requires the female to have injections of FSH and LH.

These will stimulate her eggs to mature but may give side effects, such as headaches.

The mature eggs will be extracted in a medical procedure and then incubated or injected with a male partner's sperm.

The eggs will then be stimulated to divide and form embryos before one or two are implanted into the uterus.

There will be more embryos created than are implanted.

These can be frozen, or used later, or donated to others, or research.

Otherwise they can be destroyed.

They are the property of both of you, so you can decide the outcome.

The success rates are less than 40%, so you may find this emotionally difficult.

The percentage decreases with age.

It may also lead to a multiple birth, which is higher risk to the mother and the foetus.

Further attempts at IVF will be costly as they will need to be carried out privately.

So if you've got some of those key points in your answer there, then well done.

And that brings us to the end of today's lesson, using hormones to treat infertility.

So here's our summary.

Infertility is the inability of an individual to reproduce sexually.

In adult human females some types of infertility are caused by problems with hormone levels that control the menstrual cycle.

Hormones can be used as a treatment for these types of infertility to promote natural pregnancy.

Hormones are also used as part of an IVF treatment, where embryos are created and implanted in the woman's uterus.

FSH is used to mature eggs, and LH to release them.

There are drawbacks in IVF such as success rate, chance of multiple births and emotional impact.

Individuals considering IVF must evaluate the procedure, deciding whether the benefit outweighs the drawbacks.

So well done for your working today's lesson, and I'll see you soon.