The 411 | Surviving the first trimester

Pregnancy is a truly wonderful phase for you and your partner. As you take a step towards motherhood, and before your little one arrives, you are responsible for giving them a healthy body and a nurturing environment to grow in.

The first trimester is one of the most important and complicated phases of your pregnancy. A lot happens during these 3 months as it is your baby’s fastest growth rate, morphing into a recognisable foetus from a mass of cells. Because of this rapid development, the probability of a miscarriage is high and so this precious phase often comes with an endless list of do’s and don'ts, sometimes contradictory depending on the source you read.

The following 5 recommendations should provide a useful starting point to reduce the risk of complications or miscarriage in the first trimester.

1. Smoking

Are you someone who likes to have a cigarette or two? Now is the time to quit! Every cigarette you smoke contains over 7,000 chemicals, including 70 which are linked to cancer. Smoking cigarettes can restrict the essential oxygen supply to your baby, as a result, their heart has to beat harder every time you smoke.

Research suggests active smoking in pregnancy results in a higher risk of miscarriage (23%) compared to non-smokers, with second hand / passive smoking posing a risk of 11%(1). Smokers are also most likely to give birth to babies that are at an increased risk of birth defects, such as preterm birth, cleft lip, low birth weight, and stillbirth.

Despite being labelled as a safer alternative for smokers, electronic cigarettes (otherwise known as e-cigarettes or vaping) are also harmful for growing babies and can damage a developing baby’s brain and lungs(2)(3). If you’re struggling to quit, consider using Nicotine Replacement Therapy and/or talk to your healthcare provider about ways to break the habit.

2. Seafood containing mercury

Mercury is a highly toxic element that can delay your baby’s development and is most commonly found in polluted water. When consumed in higher amounts, mercury can be damaging for your growing baby's nervous system and kidneys.

Large marine fish can collect high amounts of mercury through their gills and from eating smaller fish which contain concentrations of the chemical. Avoid these (e.g. swordfish, shark, king mackerel) where possible, however, not all fish are high in mercury.

Low mercury fish and fatty fish are high in omega 3 fatty acids, which are important for your baby’s development, and are recommended during pregnancy.

3. Cat litter

Pregnant women should avoid touching cat litter because cat faeces can put you at risk of getting toxoplasmosis (a rare parasitic disease) which can cause miscarriage or blindness and brain damage in an unborn baby.

Signs of toxoplasmosis include high fever, aching muscles, flu, and sore throat. The good news is that most cases of toxoplasmosis are symptomless and once you’ve been infected you cannot catch it again(4).

However, it is a good idea to have someone else clean the litter box daily but if you must change the kitty litter, make sure to wear gloves and wash your hands thoroughly afterward.

4. Hot tubs or sauna

Due to hormonal changes and increased blood supply to the skin, you are likely to feel warmer during pregnancy. Your skin is unable to effectively cool off by sweating causing your body’s core temperature to rise. This may slow down the blood flow to your internal organs which in turn could affect your baby’s development, particularly in the first trimester.

A 2003 study suggested the risk of miscarriage doubles if you use a hot tub or a sauna and rises with increased usage and when used during early gestation (particularly in the first 4 weeks of pregnancy)(5).

If you do feel an urge to have a dip in a hot tub or sauna:

• Limit time spent to no more than 10 minutes.
• Avoid sitting near the inlet that provides newly heated water.
• Avoid submerging your head, arms, shoulders and upper chest.
• Get out of the hot tub if you feel any dehydrated, dizziness, faint or lightheaded.

5. Alcohol

Who doesn’t love a cheeky cocktail at a restaurant or a large glass of red wine with dinner?

As tempting as it may be, new research has found no amount of alcohol is safe during pregnancy(6).

Consumption of alcohol in the first trimester of pregnancy can cause central nervous system problems as well as abnormal facial features and growth. It can even increase the risk of stillbirth and miscarriage, so if you are an expectant mom, it is best to avoid it altogether.

Sources

1. Beth L. Pineles, Edward Park, and Jonathan M. Samet, 2014, ‘Systematic Review and Meta-Analysis of Miscarriage and Maternal Exposure to Tobacco Smoke During Pregnancy’, Am J Epidemiol. 2014 Apr 1; 179(7): 807–823
2. Centers for Disease Control and Prevention, Accessed on 08/01/2022, ‘E-cigarettes and Pregnancy’, https://www.cdc.gov/reproductivehealth/maternalinfanthealth/substance-abuse/e-cigarettes-pregnancy.htm
3. Whittington, Julie R. MD; Simmons, Pamela M. DO; Phillips, Amy M. MD; Gammill, Sarah K. BS; Cen, Ruiqi MPH; Magann, Everett F. MD; Cardenas, Victor M. MD, PhD, 2018, ‘The Use of Electronic Cigarettes in Pregnancy: A Review of the Literature’, Obstetrical & Gynecological Survey: Volume 73 - Issue 9 - p 544-549
4. NHS, Accessed on 081/01/2022, ‘Toxoplasmosis’, https://www.nhs.uk/conditions/toxoplasmosis/
5. De-Kun Li 1, Teresa Janevic, Roxana Odouli, Liyan Liu, 2003, ‘Hot tub use during pregnancy and the risk of miscarriage’, American Journal of Epidemiology, Volume 158, Issue 10, 15 November 2003, Pages 931–937
6. Briana Lees, B.Psych. (Hons), Louise Mewton, Ph.D., Joanna Jacobus, Ph.D., Emilio A. Valadez, Ph.D., Lexine A. Stapinski, Ph.D., Maree Teesson, Ph.D., Susan F. Tapert, Ph.D., and Lindsay M. Squeglia, Ph.D., 2020, ‘Association of Prenatal Alcohol Exposure With Psychological, Behavioral, and Neurodevelopmental Outcomes in Children From the Adolescent Brain Cognitive Development Study’, American Journal of Psychiatry 2020; 177:1060-1072