A woman who uses marijuana at the time of conception or in early pregnancy can compromise the outcome of her pregnancy according to a new study in mice.
The author of the study Sudhansu Dey, Dorothy Overall Wells professor of pediatrics, cell and developmental biology and pharmacology at Vanderbilt University Medical Center, published his findings in the August issue of the Journal of Clinical Investigation. The study found that THC, the active ingredient in marijuana, can disrupt the body's finely tuned signaling system and interfere with a fertilized egg's ability to implant in the lining of the uterus.
Dey, his colleagues conducted their experiments in mice. Marijuana is known to be the most widely used illegal drug among women of childbearing age. In the body it acts by binding to two receptors, called cannabinoid receptors 1 and 2 (CB1 and 2). These are the receptors found in the brain as well as in sperm, eggs and newly formed embryos.
In normal conditions the two receptors are activated by a signaling molecule called anandamide, which is synthesized by an enzyme known as NAPE-PLD and then is degraded by another enzyme called FAAH. This balance, or "tone," of the anandamide is crucial for the embryo to develop normally.
When Dey and his team suppressed FAAH activity in the mice they found that the level of anandamide was increased, which is similar to what happens in the body of a woman who smokes marijuana causing an increase in the level of THC which binds to the same receptor as anandamide. The levels of anandamide rise when FAAH activity is suppressed in the embryos and oviduct. This prevents embryos from completing their passage to the uterus, thereby leading to pregnancy being compromised.
Dey said, "This is a major finding that if you block FAAH and disturb anandamide levels, there is a compromised pregnancy outcome. This occurs very early during pregnancy, right from the start of fertilization."
He said, "This may explain tubal pregnancies, it may be one cause of retention of embryos in the oviduct." He stressed that the experiment was only in mice.
This study has revealed what happens if you block the FAAH.
Other research, also in animals, has suggested that pregnant women who smoke pot can pass on memory problems to their offspring.