When it was discovered that one effect of oxytocin was to produce uterine contractions the obvious use for a synthetic version was clear. The oxytocin molecule is actually not very complicated, so laboratory versions were produced to help start and speed up labor.
Today, synthetic oxytocin, called Pitocin, is used extravagantly to induce and augment labor. Pitocin and oxytocin are spoken of interchangeably, but they are not the same thing. It seems like such a wonderful thing to be able to create useful contractions with the drip of an IV. There are questions, however, that have either not been adequately answered or not even asked about its effects.
The Blood/Brain Barrier
Oxytocin made by the body is produced mostly in the brain. There is something called the blood/brain barrier which keeps some molecules in the blood stream out of the brain. When Pitocin is given it is through an IV, so although it acts on the uterus it doesn't affect the brain. This can make it harder for a new mother to adjust to motherhood. The oxytocin that would normally be released increases mothering behaviors. Could this lack of oxytocin in the brain contribute to postpartum depression and lack of bonding between mother and baby? It's certainly something to be considered.
Effects on Baby
We know that Pitocin does not have the same effect as oxytocin. For instance, oxytocin is released in small pulses, which is why contractions only happen every 3-20 minutes for only about a minute. Pitocin is released in a more steady drip, causing contractions to be stronger, longer, and closer together. This is what the goal of an induction or augmentation is, after all. These increased contractions can be too much for the baby to handle. Sometimes the uterus can even become so stimulated that it can't relax. Without the breaks between contractions that allow blood flow to be restored the baby is in danger of being stressed and being rushed for an emergency C section.
Contractions and Only Contractions
When mice who didn't have oxytocin were studied they showed much less maternal behaviors than normal mice. This includes not being able to feed their pups. The strange thing is, they were able to deliver their pups normally. This lets us know that oxytocin has a role in labor, but it's not the hormone that kicks it off. Our modern understanding is that proteins from the baby's lungs begin the complex labor process once they're ready. Ironically, modern obstetrics is using it for the one thing it does NOT do, which is begin labor! This explains why so many inductions actually fail. Your chances of a successful induction improve with a favorable cervix, which Pitocin does not do.
There are definitely consequences to both mom and baby in labor with Pitocin, but what about effects in the long run? In Oxytocin Pathways and Evolution of Human Behavior by Carter, there are startling if not altogether unexpected consequenses of oxytocin given in large doses, especially at a young age.
"There also is increasing evidence that the effects of exposure to exogenous oxytocin are not
necessarily associated with increases in positive sociality. In prairie voles a single low-dose oxytocin
injection given on the first day of life facilitated pair-bond formation in adulthood. However, high
doses of oxytocin had the opposite consequences, producing animals that preferred an unfamiliar
partner (Bales et al. 2007b). Repeated exposure to oxytocin early in life in pigs also disrupted
subsequent social behavior, under some conditions producing piglets that were less capable than
normal animals of appropriate and reciprocal social interactions (Rault et al. 2013). Oxytocin
given intranasally to prairie voles during adolescence also did not reliably facilitate social behavior
and, once again, at some doses disrupted the tendency of this species to show a partner preference
(Bales et al. 2013). "
This brings to mind the seemingly anti-social behavior many of us have noticed in the younger generation. Could the huge doses of Pitocin around the time of birth interfere with brain development? Perhaps the reliance on technology is a byproduct of a reduced ability to connect with other people. It's at least plausible enough to consider.
Pitocin use in labor has been associated with autism, and those with autism show changes in their oxytocin receptors. Since we know oxytocin acts on behavior, it wouldn't be surprising. Labor where Pitocin was used increases a baby's chance of autism. It's especially pronounced in boys, where the risk is 35% greater. Hopefully these implications will be studied further. It is important to remember that our bodies are very complicated, and adding a large dose of a hormone at a very sensitive time should definitely only been done if it has been thoroughly studied and the benefits outweigh the risks.
I'm not saying that an induction or augmentation is never warranted, or even that Pitocin isn't the best choise for it. I mainly wanted to point out that PITOCIN IS NOT OXYTOCIN. It's a drug, and should be used with the same level of informed consent as any other.