Nicotine itself leaves the fetus relatively quickly (half-life around 2.5 hours in adults, longer in newborns), but its more stable metabolite, cotinine, stays much longer, acting as the primary marker for exposure, with a half-life of 15-20 hours in the fetus, meaning it can be detectable in fetal blood, amniotic fluid, and eventually meconium for extended periods, reflecting exposure primarily in the second and third trimesters.
The effects of nicotine are seen in every trimester of pregnancy, from increased spontaneous abortions in the first trimester, to increased premature delivery rates and decreased birth weights in the final trimester.
The half-life of nicotine is approximately 2.5 hours in adults15 and 9–11 hours in newborns,16--one of the shortest half-lives of drugs used during pregnancy17.
Nicotine from a vape passes easily from the mother to the baby via the placenta in the same way when tobacco is smoked7. Vape use in pregnancy may adversely affect birth outcomes by reducing birth weight and causing premature delivery4.
Nicotine can cross the placenta and cause a significant withdrawal syndrome in newborns. Nicotine metabolite levels, particularly 3-OH cotinine, can be measured in the urine and may be the only positive lab result in a withdrawing infant.
Although different nicotine and metabolite patterns exist in meconium versus umbilical cord tissue, this work indicates that either specimen can be used to detect third-trimester fetal nicotine exposure.
The highest levels of poisoning can result in neuromuscular blockade, respiratory failure, and death. Small ingestions could be deadly. With an estimated median lethal dose between 1 and 13 mg per kilogram of body weight, 1 teaspoon (5 ml) of a 1.8% nicotine solution could be lethal to a 90-kg person.
And smoking while you're pregnant can cause serious problems, too. Your baby could be born too early, have a birth defect, or die from sudden infant death syndrome (SIDS). Even being around cigarette smoke can cause health problems for you and your baby. It's best to quit smoking before you get pregnant.
Get ready. If you're not pregnant, choose a quit date that works for you. If you're pregnant, it's best if you can stop smoking or vaping right away.
E-cigarettes in pregnancy
E-cigarettes are fairly new and there are still some things we do not know. However, current evidence on e-cigarettes indicates they are much less risky than smoking.
Frequent urination is helpful because nicotine, cotinine, and most tobacco toxins are removed from the body through urine. Nicotine dissolves in water present in the body, and the liver expels nicotine through the urine. Drinking lots of water also helps reduce the desire to smoke.
In the newborn, withdrawal from nicotine can present in a similar way to opiate withdrawal including irritability, high tone and tremors. Both opiate and nicotine withdrawal will result in high Neonatal Abstinence Scoring System/Finnegan Scores, making the 2 difficult to distinguish.
Nicotine withdrawal involves physical, mental, and emotional symptoms. The first week, especially days 3 through 5, is always the worst. That's when the nicotine has finally cleared out of your body and you'll start getting headaches, cravings, and insomnia. Most relapses happen within the first 2 weeks of quitting.
Prevalence of vaping in pregnancy (four studies) was between 1.2% and 7.0% overall, and <1% among nonsmokers. Twelve studies reported patterns of use, but findings were inconsistent. Twelve of 14 studies asking why pregnant women vaped reported that most vaped to reduce or quit smoking.
In pregnant women who smoke or use NRT, nicotine crosses the placenta, concentrates in fetal blood and amniotic fluid, and is detectable in breast milk during lactation (Jordanov, 1990; Lambers and Clark, 1996; Luck and Nau, 1987).
Prenatal nicotine administration also has been found to decrease cell numbers and/or cell size in numerous brain regions, including cortex, hippocampus, cerebellum, brainstem, somatosensory cortex, cuneate nucleus and hypothalamus (29–33, 39,123–126).
Using electronic cigarettes, called vaping, during pregnancy is not safe. Most electronic cigarettes contain nicotine, which permanently damages a baby's developing brain and many other organs. Electronic cigarettes also are called e-cigarettes.
Maternal cigarette smoking during either the first or the second trimester of pregnancy, even as low as 1–2 cigarettes per day, was associated with increased risks of preterm birth.
If you're seeking pregnancy-safe vape alternatives, consider nicotine replacement therapy (NRT). These options, such as nicotine gum or patches, provide controlled doses of nicotine without exposing you or your baby to the harmful chemicals found in vape products.
Point-of-care screenings and counseling for behaviors such as alcohol use and domestic violence are common in prenatal care and accepted by clinicians. Over the past several decades, tests for cotinine and other tobacco byproducts have become available and are used in research settings to identify pregnant smokers.
You'll be offered a carbon monoxide test at your 1st antenatal appointment. During the test, you'll be asked to blow into a machine. The machine measures the amount of carbon monoxide in your body. If the result is 4 or more, your midwife will ask if you or someone else in your home smokes.
Maternal smoking during pregnancy is a major risk factor for sudden infant death syndrome (SIDS), with nicotine likely as the active agent (1). The cause of the majority of SIDS deaths is unknown.
The window of detection for tobacco in meconium appears to be the 3rd trimester; however, low exposure in this trimester failed to be detected. These results will aid physicians in educating women who are pregnant or thinking about becoming pregnant on the negative consequences of smoking during pregnancy.
Tobacco's impact on child growth
Maternal smoking during pregnancy is strongly linked to preterm birth, low birth weight and restricted fetal growth – all predictors of stunting by age two. Heavy smoking during pregnancy harms the baby, with stronger effects the more the mother smokes.