Can a Father's Weed Use Affect His Baby? What the Science Says

A father's marijuana use before conception can have a real impact on his baby's health. Recent research suggests cannabis can degrade sperm quality — and with it, the health of the fetus and the newborn. Possible problems include a higher risk of congenital abnormalities, low birth weight and long-term developmental issues.

What problems can a father's marijuana use cause for his baby?

A study from the University of Bradford in England showed that a man's cannabis use can significantly affect the embryo. Sperm cells take more than three months to fully mature and can carry residues of the drug with them, which poses risks to embryonic development.

Active or passive smoker: why quitting weed before conceiving matters

Paternal cannabis use has negative effects on embryonic development. Men should stop smoking marijuana at least three months before trying to conceive — that's how long sperm take to fully develop.

The teratogen risk in marijuana

Geneticist Gilda Mayén Molina, head of the Genetics Unit at Hospital Ángeles Lomas, points out that marijuana contains teratogenic agents — substances capable of causing congenital malformations.

That's why men are advised to avoid cannabis use for at least three months before conception, and women for at least six. Animal studies have shown that paternal marijuana use can affect fertilization, implantation and embryogenesis.

A father's drug use can affect the baby

If you're trying to get pregnant, it's crucial to plan the pregnancy and avoid marijuana use if you're not relying on dependable fertility control methods.

Long-term effects and studies in newborns

Although research into the effects of cannabis keeps growing, its long-term effects are still not fully understood, especially in newborns and throughout childhood.

What has been observed, however, is that paternal marijuana use can cause epigenetic changes in the nervous system, potentially reprogramming neuronal function and being passed down to future generations — affecting not only children but grandchildren and great-grandchildren too.

The takeaway

The scientific evidence underscores how important it is to avoid marijuana before conception, given the potential risks to embryonic development and to the long-term health of future generations. Couples planning to have kids should take these findings seriously and do what's needed to minimize the risks.

Marijuana use during pregnancy: risks and recommendations

Marijuana use during pregnancy can have serious consequences for fetal development and the newborn's health. According to the genetic medicine expert, cannabis use in pregnant women has been linked to complications such as preterm birth, intrauterine growth restriction and even severe heart defects.

Risks of using marijuana while pregnant

Using marijuana during pregnancy can lead to several health problems for the baby. The genetic medicine specialist warns that women who use cannabis risk giving birth early and having low-birth-weight babies. Cases of serious heart disease in newborns have also been reported.

Using marijuana for pregnancy nausea

Psychiatrist César Velasco Téllez, head of the Mental Health Department at Mexico's National Institute of Perinatology (INPer), notes that many pregnant women use marijuana to relieve nausea.

That use isn't recommended, though, because of the negative side effects it can have. Velasco Téllez stresses that marijuana use during pregnancy can affect the newborn's neurological health, showing up as behavioral disorders and emotional problems during childhood.

Safe alternatives for treating nausea

Both experts agree that pregnant women should talk to their doctor to find safe options for treating nausea. Marijuana should never be one of them, given the risks it poses to both mother and fetus.

How other substances impact fetal development

Beyond marijuana, other substances can also affect embryonic and fetal development. They're linked to preterm births, low birth weight and fetal distress, and they can harm the developing baby's brain in ways similar to their impact on the brains of adult users.

Marijuana use during pregnancy carries significant risks for the baby's health. Pregnant women should avoid it and look for safe alternatives to manage nausea and other pregnancy symptoms. The developing baby's health comes first — and marijuana should not be considered a viable option.