Teratogens and Teratogenesis (Nursing)

00:00 Now I wanna talk about something that's really serious when it comes to placental drug transfer. We just call it the thalidomide disaster.

00:09 Most people, obviously, if you weren't even born during this time, it's in the back of their minds when you worry about taking a medication when you're pregnant.

00:17 Now, no one knows how many miscarriages this drug caused but it's estimated that in one country, in Germany alone, 10,000 babies were born affected by thalidomide.

00:29 Now, the reason this happened is because thalidomide was marketed as a mild sleeping pill safe even for pregnant women.

00:38 Also in the 1950s and the 1960s, thalidomide was used to treat morning sickness during pregnancy.

00:46 Well, if you take trouble with sleeping and morning sickness, those were huge numbers of pregnant women this drug that was thought to be safe was recommended for.

00:58 Well, it ended up finding out that it was not safe for pregnant women.

01:02 In fact, it caused severe birth defects.

01:04 Thousands of babies worldwide were born with malformed limbs.

01:09 Now you see an example, a picture of a child here, it's one example of the malformed limbs caused by this drug.

01:16 Now, thalidomide is still used today for very specific reasons.

01:19 Obviously, not given to pregnant women but it has another role in place in a correct administration that can be beneficial to patients but this was a disaster.

01:32 A medication that we thought to be safe, particularly for pregnant women, was not.

01:38 So let's give it the official name, teratogen.

01:42 Now, thalidomide is an extreme example of teratogen.

01:46 It's an agent that can disturb the development of the embryo or fetus.

01:50 Now, clearly you saw a visual picture of what that ended up looking like for thousands of children who are born after thalidomide.

01:58 So just underline that word, teratogen, so it sticks out in your mind.

02:03 Remember, thalidomide is an extreme example of that but it's one that will always stick with you.

02:10 So know that that's what we're worried about with pregnant moms taking medications.

02:15 We're worried about placental drug transfer and we just call that name teratogen.

02:20 Those are the ones we don't want a mom to take because it disturbs the development of the embryo and the fetus.

02:25 Now, teratogenesis is the process by which it happens.

02:29 So teratogen is the source that caused it.

02:32 Teratogenesis is the creation of terato, right? So that's the process by which these congenital malformations are produced in an embryo or a fetus.

02:42 So just a couple of vocabulary words for you to be familiar with that you'll see in literature.

02:46 Now we talked about birth defects.

02:48 You'll see the term gross malformations.

02:52 That's a pretty emotionally-charged word but this is what they mean.

02:56 Now before I break down what gross malformations are, I just wanna remind you less than 1% of all birth defects are caused by drugs.

03:06 So if your baby is in that less 1%, I understand it's a huge deal but I want you to keep in mind that it's only less than 1% of all birth defects are actually caused by drugs.

03:18 There's lots of reasons and causes for birth defects so it makes it very difficult to identify the cause or the teratogen.

03:26 It's pretty tough to narrow down sometimes.

03:28 Now hopefully we would do it quicker than they did with thalidomide in the 50s and 60s but still, it takes a while sometimes to make that connection.

03:38 So there's only a few drugs that are actually considered proven teratogens and that's why.

03:43 Okay, so let's look at some of the gross malformations.

03:46 Cleft palate, clubfoot which you see pictured there, and hydrocephalus.

03:51 Now when we are researching for this presentation, if you'll Google hydrocephalic babies, I was taken aback.

04:01 I could not take my eyes away from those pictures.

04:05 They are pitiful pictures of children with enormously enlarged heads.

04:10 So lots of kids have hydrocephalus and it's not as extreme but there's some very extreme pictures of children with severe, severe hydrocephalus.

04:21 I mean, they're just extra fluid in the ventricles of their brain but particularly with babies, their heads can become extremely swollen.

04:28 Some of them almost look like alien babies to me so if you wanna have a visual picture of what a severely extreme case would look like, there are plenty available on Google for you to take a look.

04:40 So you have the two categories of birth defects: gross malformations or neurobehavioral or metabolic abnormalities.

04:48 Those are a little trickier to diagnose.

04:50 The cleft palate, you're gonna see immediately.

04:52 Clubfoot, you're gonna notice that right away.

04:55 And hydrocephalic becomes evident pretty quickly.

04:59 So teratogenesis, genesis means the making of new, right? This means the creation or the process of these birth defects.