The data shows that 11-38% of pregnant women suffer from constipation. Causes of constipation in pregnancy are numerous. Elevated levels of estrogen and progesterone slow the intestine and the colon becomes even lazier. Pregnant women move less and take iron and calcium supplements which also cause constipation.
The main challenge in treating constipation in pregnancy is that treatment should help the mother, but also protect the fetus. So far, we have learned how to cure constipation. Now we just need to see which of these methods of treatment are safe for the baby. The regulatory body in the United States (Food and Drug Administration; FDA) classified the drugs into five groups.
Two problems remain unresolved.
As a matter of fact, drug research is rarely conducted on pregnant women, which is why there is little data on which to base a decision about the safety of the fetus. Therefore regulatory authorities transfer that decision to the doctors. Before you take medication during pregnancy, ask your doctor. If regulatory bodies can’t tell what is safe, how can doctors?
Due to the lack of evidence on drug safety in pregnancy, regulatory authorities in the United States (FDA) and Europe (European Medicines Agency; EMA) have established a registry where potential side effects are monitored in pregnant women who take medication. So we will have some data after all. Regulatory bodies established the register, but they are paid by the pharmaceutical companies. One problem regarding constipation is that there is no registry concerning medication that solves constipation in pregnancy.
Another problem is that the risk of birth defects is equal in categories C, D and X, and only the benefits for the mother are different. So the drug in category C is not safer for the fetus than the drug in category D. However, the drug in category C has greater benefits for the mother.
Let’s see what we do know about the safety of treating constipation in pregnancy.
What is safe in pregnancy?
Water, exercise and fiber in the diet are considered safe in pregnancy. They have not been tested on animals nor on pregnant women, but do we know that they are safe based on of long-term use. It is similar with bread: you can eat it in pregnancy, though its effects haven’t been tested on animals or humans. That is why the first step in treating constipation during pregnancy is regular exercise and an adequate intake of water and fiber.
In pregnant women, the first-line treatment of constipation is to increase the intake of water and fibers, as well as being physically active (unless they are on recommended bed rest).
Psylliumdoes not cause damage to the fetus. This was determined on the basis of research on pregnant women. Psyllium is not reabsorbed into the blood and can be taken during breastfeeding.
Lactulose is tested on animals and doesn’t cause damage to the fetus. No studies have been conducted on pregnant women. Only 3% of lactulose is reabsorbed from digestion into blood, so a minimal amount passes into the milk, which can be used during breastfeeding. Research shows that lactulose is safe for children from the first day they are born. It belongs to class B medications according to the classifications by the FDA.
Senna does not cause damage to the fetus but can cause contractions (spasms) of the uterus and preterm delivery. This was determined on the basis of research on pregnant women, and the FDA classified it as a class C medication. Only 5% of senna glycosides are reabsorbed into the blood.
There is no testing for bisacodyl on animals or in pregnant women. An investigation was conducted on 16 women who had recently given birth and had mother’s milk but did not breastfeed. They were given bisacodyl, which did not appear in the milk. Based on that it was decided that it can be given during breastfeeding.
Natural fibers in the diet and nutritional supplements with fiber can be used in pregnancy and during breastfeeding.
If this does not help, osmotic laxatives may be used during pregnancy, with caution towards avoiding dehydration and electrolyte abnormalities.
It is better to avoid stimulant laxatives because they can cause uterine contractions.