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Pregnancy Risk Factors - Vital Information About Risk Factors Which Present During Pregnancy

There are cases of pregnancy where certain conditions tend to develop along the way thereby putting the baby and the mother’s health at a greater risk. Along the course of pregnancy, some pregnant women are exposed to certain substances, drugs, chemicals, infections and radiation which may negatively affect the mother as well as the baby’s health.

1. Prescription and OTC (over the counter) drugs in Pregnant Women

Whether aware or unaware of their pregnancy, some women have taken drugs such as isotretinoin, anticonvulsants, antibiotics, lithium, ACE inhibitors, warfarine and thalidomide which can be harmful to the baby’s health. Intake of these drugs actually increases their baby’s risk for birth defects. Some drugs work by blocking the activities of the folic acid or folate which play vital roles in preventing the onset of neural tube defects and other birth defects.

According to research, more than 90% of pregnant females are taking social drugs, over the counter drugs and prescription drugs during their pregnancy. As a general rule, pregnant women should avoid using drugs during pregnancy unless necessary because they may contain substances which may cause harm not just to the mother’s health but to the fetus as well. Around 2-3% of birth defects have actually resulted from the use of drugs.

2. How can drugs affect the health of the developing fetus

When drugs are taken within 20 days after the process of fertilization, only two scenarios are possible. Either the drug completely kills the foetus or it doesn’t incur any adverse effect to the foetus. According to research, fetuses are very resistant to many forms of birth defects during this period. But fetuses are very vulnerable to birth defects from the 3rd to 8th week after fertilization. During this period, the essential organs of the body are forming and developing.

Intake of drugs during this period may trigger miscarriage or may cause a permanent birth defect. In some cases, permanent birth defects are induced but they are only noticed later in life. If drugs are taken after the development of organs, it may not necessarily trigger the development of some birth defects but it may alter the functions and growth of the organs and tissues affected

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3. More about the effects of drugs on your fetus

Drugs taken my pregnant women are usually taken by the fetus through the placenta which delivers oxygen and nutrients to the developing baby in the uterus. Drugs can directly affect the neonate which may damage or affect the normal development of the fetus. It may trigger the onset of birth defects and even death in babies.

Drugs may also change the ways how placenta works. It may trigger the narrowing of the blood vessels which results to a reduced supply of nutrients and oxygen from the mother to the baby. This is one of the main reasons why some babies are underdeveloped and underweight.

Also, drugs may also trigger a forceful contraction of the uterus which may cause an injury to the fetus. In some cases, it reduces the supply of blood and induces pre-term labour and delivery.

The use of nicotine, alcohol and cocaine also bring adverse effects to the human body. It increases the pregnant women’s risk for miscarriage while babies are out at a greater risk for birth defects and being underweight.

4. Alcohol consumption during pregnancy

The use of alcohol can actually cause the development of mental retardation and fetal alcohol syndrome. Meanwhile, women who have used cocaine during their pregnancy are at an increased risk for placental abruption, a condition characterized by the premature detachment of the placenta. It may also prevent the growth of the fetus and promote stillbirth and premature birth.

Alcohol consumption actually doubles the risk of pregnant women for miscarriage. Though the exact quantity of alcohol required to trigger the onset of fetal alcohol syndrome and other related disorders is yet unknown, doctors strongly advised pregnant women to abstain from taking alcohol during pregnancy.

Fetal alcohol syndrome is characterized by small head, inadequate growth and development before and after delivery, mental retardation, abnormal behavioural development and facial defects. It may even trigger an abnormal functions and position of the joints. In some cases, excessive consumption of alcohol may trigger the onset of heart defects.

5. Cigarette smoking and pregnant women

Pregnant women should also avoid cigarette smoking during this crucial period. Cigarette smoking increases the risk for stillbirth and other pregnancy complications such as placental previa, premature membrane rupture, placentral abruption and premature birth. It may also hinder the growth and development of the fetus. According to research, cigarette smoking elevates the children’s risk for mental retardation and other behavioural problems later on.

Many babies are born underweight. One of the most common culprits behind this phenomenon is cigarette smoking. According to research, the more a pregnant woman smokes, the lesser is the weight of the babies. In fact, babies to smoking mothers have an average weight of 6 ounces less than the weight of babies who are born to mothers who do not smoke.

Smoking moms increase their baby’s risks for birth defects of the brain, face and heart. Also, babies are put at a greater risk for Sudden Infant Death Syndrome (SIDS). Other complications include preterm labour, stillbirths, miscarriages and uterine infections.

Also, cigarette smoking heightens the children’s risks for deficiencies in intellectual, behavioural and physical growth and development. Cigarette smoking actually harms the baby through its carbon monoxide and nicotine content. Carbon monoxide plays a vital role in reducing the supply of oxygen to the blood vessels while nicotine triggers the release of certain hormones that facilitate in the constriction of the blood vessels which supply blood to the placenta and uterus. In effect, less nutrients and oxygen are delivered to and received by the foetus.

5. Caffeine during pregnancy

Though there is still insufficient evidence relating caffeine consumption to birth defects, doctors strongly advise pregnant women to stay away from caffeine during their pregnancy. According to research, caffeine may negatively affect the fetus’ heart rate. Also, it plays a vital role in reducing the supply of blood to the placenta as well as in reducing the abruption rate of iron which may lead to anaemia. There are scientific evidences claiming that excessive intake of caffeine increases a pregnant woman’s risk to have pre-term delivery, premature birth, stillbirth, miscarriage and baby with low birth weight.

6. Opiods and amphetamines in pregnant women

The use of opiods such as morphine, methadone and heroin rarely ends up with birth defects however, according to research, it may cause substance addiction to the fetus. Some fetuses may experience withdrawal symptoms within 6 hours to 8 days after delivery. When used during pregnancy, opiods can increase the likelihood for certain complications which include pre-term delivery, abnormalities and miscarriage. Meanwhile, amphetamines can trigger the development of birth defects especially in the heart.


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All articles on the blog and website are intended as information only. Please do not consider any of the information provided here as a substitute for medical advice. At all times seek medical advice directly with your own doctor and medical team.


This website was formerly Merrion Fetal Health. The clinic has undergone a rebrand and is now known as Merrion Ultrasound.