What substances cross the placenta?
Other substances that pass through the placenta include red blood cell antigens, carbon dioxide, oxygen, some viruses, and nutrients. The placental size increases throughout the pregnancy, but not in constant proportion.
What are 2 substances that pass across the placenta that the developing fetus needs?
Oxygen and nutrients from the mother’s blood are transferred across the placenta to the fetus.
What substances are transported across the placenta by simple diffusion?
- Oxygen. Oxygen is a small molecule which readily crosses the placenta by passive diffusion.
- Carbon dioxide. Carbon dioxide also crosses the placenta readily by passive diffusion.
- Amino acids.
- Fatty acids.
- Electrolytes, vitamins, and water.
- Human chorionic gonadotropin.
- Human placental lactogen.
What materials does not cross the placenta?
Alcohol, for example, readily reaches the embryo in fairly high concentrations. On the other hand, high molecular-weight drugs like heparin (20,000 daltons) do not cross the placenta. It is therefore widely used to treat hypercoagulation during pregnancy.
What harms the baby while pregnant?
Tobacco, alcohol and drugs can have harmful effects on anyone’s health. When a pregnant or nursing woman uses these substances, her baby also is exposed to them, for all substances cross the placenta through the umbilical cord and enter into the baby’s bloodstream.
What substances should I avoid during pregnancy?
Chemicals to avoid when you’re pregnant or breastfeeding
- Pesticides and herbicides. Some pesticides (bug killers) and herbicides (weed killers) are known to affect developing and newborn babies.
- Cleaning products.
- Mosquito repellent.
- Arsenic-treated timber.
- Nail polish.
- Paint and lead-based products.
Can a virus be transmitted through the placenta?
Some viruses can pass generationally between mother and fetus in utero (in the case that breaks in the placental barrier are present, during delivery, or during breastfeeding). HIV, toxoplasma gondii, rubella, cytomegalovirus, and herpesviruses have been proven to transfer from mother to child via these routes.
Do hospitals sell placentas?
Some hospitals still sell placentas in bulk for scientific research, or to cosmetics firms, where they are processed and later plastered on the faces of rich women.
What drugs pass through the placenta?
Drugs which have been shown to undergo significant placental metabolism include azidothymidine, dexamethasone, and prednisolone (van der Aa et al., 1998). The anticonvulsant oxcarbazepine (but not carbamazepine) is also metabolized to some extent by the human placenta (Pienimäki et al., 1997; Myllynen et al., 1998).
Do all drugs pass through the placenta?
Almost every drug passes from the mother’s bloodstream through the placenta to the fetus. Illicit substances that cause drug dependence and addiction in the mother also cause the fetus to become addicted.
Which trimester does the baby grow the most?
The second trimester is a time of rapid growth for your baby (called a fetus). Most of the brain’s development begins now and will continue after your baby’s birth.
Can I hurt my baby by pressing on my stomach?
Not much can beat the feeling of a toddler running to you for a big hug. And, for most patients, the force of a 20- to 40-pound child bumping your belly is not enough to harm the baby.
How does a drug cross the placenta membrane?
Drugs cross the placenta largely by simple diffusion. Factors affecting drug transfer are similar to those affecting transfer across other biological membranes and include the molecular mass, lipid solubility, and degree of ionization of the compound.
What kind of anesthetics cross the placenta?
Specific Anesthetic Agents. Thiopental, propofol, benzodiazepines, and ketamine all cross the placenta, although only benzodiazepines are noted to produce significant fetal effects. Opiates all cross the placenta to some extent (amount is variable) – from a respiratory standpoint, newborns are most sensitive to maternal morphine.
How is placental function, function and drug transfer?
Placental structure, function and drug transfer. Placental drug transfer is dependent on the physical properties of the placental membrane and on the pharmacological properties of the drug. Almost all anaesthetic drugs cross the placenta easily, with the exception of the neuromuscular blocking agents.
Are there any opiates that can cross the placenta?
Opiates all cross the placenta to some extent (amount is variable) – from a respiratory standpoint, newborns are most sensitive to maternal morphine.Fentanyl appears to be safe if given at < 1 ucg/kg. Epidural opiates produce minimal effects.