Hard Labor and Thyroxine Levels
A recent study coming out of Holland says that expectant moms with low levels of a hormone called thyroxine, produced by the thyroid gland, tend to have more difficult labors. It has long been known that too little thyoxine can lead to complications of pregnancy, for instance miscarriage, pre-eclampsia, and premature delivery. Now, the Dutch research team tells us that even baseline normal levels of thyroxine can cause problems.
Researchers from the University of Tilburg feel that this hormone problem is more common than many realize and may affect as many as 10% of all pregnancies. It seems that the babies of mothers with low thyroxine levels tend to have babies ill-positioned for delivery. While the head may be down, the baby tends to face the wrong direction. This places pressure on the back and on the tailbone and often prolongs labor. While labor and delivery are more difficult and take more time, there is also a heightened risk for medical interventions such as Caesarean sections.
The research team studied 1000 pregnant women in good health and discovered that lowered levels of thyroxine at 36 weeks gestation had a very strong link to an abnormal fetal position of the head which often necessitated an assisted delivery through forceps, ventouse, or C-section. The team believes that not enough thyroxine makes the baby a bit sluggish so it doesn't get into the best position for labor and birth and ends up stuck facing the wrong way.
To support the team's theories, they pointed out recent discoveries that suggested a connection between low thyroxine during pregnancy and poor motor development in 24 month olds. The Tilburg researchers believe that prenatal care should include routine bloods tests to screen for thyroxine levels so the problem can be identified and remedied prior to the labor and delivery.
During the course of fetal development, babies only begin to manufacture their own thyroid hormones at the age of 20 weeks gestation. Until then, the baby must depend on its mother to deliver the hormone to its blood stream. Lead author of the study, Professor Victor Pop said, “It follows that impaired maternal thyroid function could also influence fetal movement."
This theory still needs a lot of research to give it backbone, but it does seem a promising avenue to explore. Thanks to this Dutch team, we now know for sure that women can benefit from having their thyroid hormone levels checked during their pregnancies.