BusyMamaMD

“32 week pregnant female, en route to the hospital via ambulance.  She is bleeding heavily with a suspected abruption.  10 minutes out.”  I received the call at about 2am.

I arrived at the hospital just before the ambulance. The elevator doors opened and two emergency medical technicians entered the Labor and Delivery unit with Michelle* on a stretcher.  The nurse quickly ushered them to Labor Room 1, which was set up and ready. Michelle was pale and shaking.  Her face was tear-stained as she clutched her pregnant belly with her blood-soaked hands.  She was crying for her husband, who was standing terrified behind her, holding their 2 year old son.  We moved her to the bed and I saw the liter of blood and clot underneath her. The fetal heart rate was 45, less than half the normal rate, when we rushed her back for an emergency Cesarean section.  As the anesthesiologist placed the oxygen mask on her face, she begged me to save her baby girl before she drifted off to sleep.

The team acted quickly and the baby was out in minutes.  The little girl was pale, limp, and covered in blood.  I handed her immediately to the waiting pediatrician and team.  I finished Michelle’s surgery, waiting for a cry or a whimper.

The little baby girl was dead.

The pediatrician and I walked to the waiting room to tell Michelle’s husband that his daughter had passed away.  But, that was not the worst part.  I still had to tell Michelle once she awakened from her anesthesia.  She looked terrified when I entered the room.  When she saw my face, she knew.  I will never forget her gut-wrenching cry.

Michelle was a smoker.  She had a known complication of smoking: placental abruption.  Her placenta detached too early, causing the baby to bleed to death.  Although many mothers that smoke do not have any obvious complications, she did.  She was not the first and will not be the last.  I have seen other smoking mothers with placental abruption.  I have seen smoking lead to preterm deliveries and neonatal ICU stays.  I have seen smoking lead to the SIDS death of a 1 month old baby boy.  I cringe when a mother tells me, “I smoked with my other kid and he’s fine” or “My mom smoked with all of us and we turned out ok.”  True as that may be, not everyone is so lucky.  Russian Roulette does not kill everyone that plays.

What does smoking do to a baby?  Most people have heard that it can lead to low birth weight babies.  What’s the big deal?  Well, “low birth weight” itself might not be a big deal to a patient, but the reason behind the low birth weight is a big deal.  Babies are smaller because they are deprived of oxygen and nutrients.  Oxygen is important.  Obviously we need it to live.  Just as we need it, the developing fetus depends on it to grow and develop normally.  When a woman smokes, her blood vessels (and the placenta’s blood vessels) get smaller, delivering less oxygen to her and also to her baby.  Smoking also causes permanent changes in the blood vessels of the placenta, making it harder for baby to receive oxygen from its mom.  Smoking also results in increased levels of something called “carboxyhemoglobin” in the blood.  This carboxyhemoglobin competes with oxygen, blocking the oxygen from reaching the tissues.  Therefore, even if oxygen is available, it has a harder time getting to the placenta and to the baby.

Even if oxygenation was not enough of an issue, various toxins, including nicotine, in cigarettes can also have direct effects on a growing fetus.  Animal studies have shown that nicotine can cause changes in the fetal brain and harm the fetal lungs (1, 2), which explains why many children of smokers have higher risks of disorders than affect these organs.

The lack of oxygen and toxic chemicals lead to more than just a small baby.  As in the case of Michelle, it can cause a placental abruption.  If the placenta detaches before the baby delivers, the baby can bleed to death quickly.   Women who smoke have a 2.5-fold higher risk of an abruption than a nonsmoker (3).  This risk is even higher in women who smoke with high blood pressure.  Smoking can also lead to miscarriage and stillbirth without abruption.  It can cause preterm labor and delivery.  Women who smoke are up to 2.4 times more likely to have a preterm delivery, especially very early deliveries prior to 32 weeks (4).  Evidence exists that it can even cause certain congenital malformations.  Some studies have shown higher risks of cleft lip and palate as well as gastrointestinal, heart and limb abnormalities.

Smoking continues to affect the baby after he or she is born.  Multiple studies have shown that the risk of SIDS (sudden infant death syndrome) is higher is smokers than nonsmokers.  In addition, there is also an association with diabetes, behavior problems (such as ADHD), asthma, schizophrenia, and various neurologic disorders.   A recent study following children of smokers showed persistent DNA changes from smoking that persisted into adulthood (5).

Nicotine replacement products, such as a nicotine patch or gum, can be used.  Althugh the products contain a pregnancy warning, the warning is there since nicotine is known to cause problems (as discussed above).  However, given that nicotine replacement is no worse than cigarettes, it is a great option to help someone quit smoking for good.  The prescription drug, bupropion, is another option.  Although the drug does cross the placenta, there have been no reported teratogenic effects (6).  The studies are limited, but it does appear safe.  In addition to medication, counseling can help.

Maybe smoking didn’t cause Michelle’s placental abruption.  Although I strongly suspect the smoking was the culprit, I cannot prove it.  Perhaps it was caused by something else that we don’t fully understand.  However, she will have to live knowing that quitting smoking could have potentially saved her baby’s life.  She will spend hours of sleepless nights wondering “what if.”  I understand quitting is hard.  To all the pregnant smokers, smokers contemplating pregnancy, and smokers with children: Please get help.  Resources are available.  Talk to your doctor.

References:

1. Pauly, JR and Slotkin TA. Maternal tobacco smoking, nicotine replacement, and neurobehavioral development.  Acta Paediatr.  2008; 97(10): 1331.
2. Sekhon HS and Keller JA and Benowitz NL et al. Prenatal nicotine exposure alters pulmonary function in rhesus monkeys.  Am J Respir Crit Care Med 2001; 164: 989.
3. Kramer MS, Usher RH, Pollack R et al. Etiologic determinants of abruptio placentae.  Obstet Gynecolo.  1997; 89(2): 221.
4. Cnattinguis S, Forman MR, Berendes HW. Effect of age, parity, and smoking on pregnancy outcome: a population based study.  Am J Obstet Gynecol.  1993; 168: 16.
5. Tehranifar P, Wu HC, McDonald JA et al. Maternal cigarette smoking during pregnancy and offspring DNA methylation in midlife.    2017 May 11:0.
6. Bupropion Pregnancy and Breastfeeding Warnings.  Drugs.com.  Retrieved from https://www.drugs.com/pregnancy/bupropion