A) Nausea and vomiting in pregnancy
1. This begins early in pregnancy, most commonly between the 4th and 7th week or pregnancy, peaks at about 10 weeks and usually settles by 12-14 weeks. It may last longer in some women.
2. When severe, it leads to dehydration and significant weight loss. It is then known as hyperemesis gravidarum.
3. Eat small amounts often. Avoid foods or smells that trigger the symptoms. Eating or drinking ginger products may help some women, and irritate the stomach of others. Acupressure or acupuncture may be helpful.
4. Medications to reduce nausea may be helpful for some women. These medications include metoclopramide, prochlorperazine, Dicletin and ondansetron. Corticosteroids may be considered.
B) Air travel and pregnancy
1. There is no evidence that flying causes miscarriage or early labour, though there is a slight increase in radiation. Occasional flights are not risky to you or your baby. Some pregnant women may experience discomfort during the flight e.g. swelling of legs due to fluid retention, nasal congestion / problems, and vomiting.
2. Most airlines allow you to fly up to 36 weeks (for singletons) and up to 31-32 weeks (for twins). Airlines require a letter from your doctor to state that you are fit to fly after you are 28 weeks. Most would require the letter to be dated within 1 week before the flight.
3. Flights that are longer than 4 hours in duration may increase the risk of deep vein thrombosis (i.e. blood clot that forms in your legs or pelvis) which may travel to the lungs and be life-threatening. You should regularly drink water, take regular walks around the plane and wear graduated elastic compression stockings. If you have other risk factors for a deep vein thrombosis, you may need to have injections of heparin (a medication that thins your blood and reduce the chance of deep vein thrombosis).
4. Though there is no evidence that flying causes early labour, early labour could still happen to anyone (flying or not). If premature labour occurs between 24 to 32 weeks, there is a need to be admitted to a good maternity hospital with good ICU facilities for the baby. Do some homework before your travel to find good maternity hospitals near the places that you are travelling to, and be prepared for a whopping big bill (unless you have medical insurance that covers care of premature babies at the place that you are travelling to).
C) Pelvic girdle pain and pregnancy
1. Pelvic girdle pain is pain in front and/or the back of your pelvis that can also affect other areas such as the hips or thighs. It can affect the symphysis pubis joint (also known previously as symphysis pubis dysfunction) at the front and the sacroiliac joints at the back. This is caused by the 3 joints in the pelvis moving unevenly.
2. This is common, affecting 20% of pregnant women. You could suffer from pain when you are walking, climbing stairs and turning over in bed.
3. Postural changes and avoidance of activities that may make your symptoms worse (e.g. going up and down the stairs too often, lifting anything heavy, standing on one leg) are simple measures that may help your symptoms. A referral to a physiotherapist might be useful. Warm baths, heat or ice packs and acupuncture could also help. If these measures do not help, paracetamol and aids like crutches or wheelchairs may be useful.
D) Zika in pregnancy
There are many questions about Zika in pregnancy. From the evidence so far, doctors agree that Zika infection during pregnancy (especially during the first trimester as compared to the third trimester) can be associated with the following problems to the baby:
1. Brain abnormalities including:
a) Microcephaly - small brain
b) Excessive water in the brain
c) Calcium deposits in the brain
2. Eye abnormalities
3. Possibly other structural abnormalities
4. Growth restriction of the foetus
5. Miscarriages and stillbirth
It is less clear though about the actual rates of fetal infection when the mother is infected in the first, second or third trimesters. Similarly, the rates of abnormalities when there is fetal infection in the first, second or third trimesters or not known.
If symptomatic (i.e. fever, rash, muscle / joint pains, red eye) during periods of known active Zika transmission, one should be tested for Zika with urine and / or blood tests for Zika PCR. It is widely known that Zika infection is asymptomatic in up to 80%. However there is now no good strategy for screening for Zika infection in the asymptomatic pregnant women. This is because urine and / or blood tests for Zika PCR may only be positive within 2 weeks of infection with Zika. Hence the only strategy for testing the asymptomatic women for recent Zika infection during pregnancy is to screen the mother for blood or urine Zika PCR every 2 weeks from 6 weeks pregnancy till delivery. This is highly impractical and a very expensive exercise, and may still not be able to detect all cases of maternal Zika infection in the asymptomatic pregnant women. Also the rates of fetal damage when there is maternal Zika infection is thought to be between 1-13%. Therefore the majority of maternal Zika infections probably do not result in fetal damage.
A more practical strategy is to screen for fetal abnormalities including microcephaly, excessive water in the brain and calcium deposits in the brain. If these abnormalities are present, possible causes of these conditions (including Zika infection) can then be tested for.
Whilst attention is now on Zika infection at the moment, other infections (e.g. cytomegalovirus or CMV) during pregnancy are more likely to cause sequelae to the baby. For many of these infections, there aren't good strategies to detect or treat these infections.
For now, the only practical strategies for pregnant women are:
1. Avoid being bitten by mosquitoes through wearing light-coloured long-sleeve tops and pants, sleeping in air-conditioned rooms or with mosquito nettings, and using insect repellents with DEET 20 to < 50%.
2. Using condoms for sex throughout pregnancy as the partner could be asymptomatic while having Zika infection.
E) The haze in Singapore and pregnancy risks
There is not a lot of data on this issue. We have to go on basic principles about what we know about exposure to possible harmful agents. The three principles are:
1) Exposure after the first trimester is not likely to cause fetal abnormalities. The organs of the fetus are completely formed by 8-9 weeks and there is only growth and maturation of the fetus and its organs after that. In theory, substances may cause abnormalities in the fetus especially if exposed in the first trimester. This increase in abnormalities, if any, is likely to be small in view of what we know of most substances. Whether prolonged exposure in the second and third trimesters will increase the risk of preterm labour and intrauterine growth restriction of the fetus is speculative at best.
2) Any detrimental effects of exposure to the haze is related to the duration of exposure. The longer the duration of the exposure, the higher the risk of the exposure. If exposed to the haze over months and years, the detrimental effects are more likely than if exposed over days and a few weeks.
3) Any detrimental effects of exposure to the haze is related to the severity of the pollution. The widely circulated PSI is a measure of the severity. The higher the PSI, the higher the theoretical risk.
There isn't much that we can do to reduce the severity or duration of the haze. However it makes sense to wear the N95 mask if one is going to be outdoors for a prolonged period of time, and to stay indoors with windows and doors closed as much as possible.
Comentarios