Effect of Reducing Caffeine Intake on Birth Weight and Length of Gestation, Essay Example

Background to the paper

Recent research has shown scientific evidence that prenatal nutrition is associated with the health of the pregnant women as well as fetal development and growth.  Increased caffeine consumption during pregnancy has been of main concern with regards to maternal nutrition and a hot topic of research especially in relation to fetal pre-term birth and low birth weight.   Previous studies found a correlation between women who consume caffeine at more than 300 mg per day during pregnancy and babies born at 100-200g below the birth weights of babies from mothers who consumed a lower of amount caffeine.  In addition, other studies have found a correlation between caffeine and pre-term births (Fifer240). Due to research focused on caffeine and pregnancy, the World Health Organization (WHO) recommended that women reduce intake of caffeine to below 300mg/day during pregnancy.  Other organizations, such as the American College of Obstetricians and Gynecologists and Norwegian Food Safety Authority have recommended a maximum of 200 mg of caffeine (Shmidt and Romitti).

Caffeine is a chemical compound that is found in various drinks such as coffee, tea, energy drinks, as well as in chocolate.  Caffeine is known to have biological effects such as neurological stimulation, increased release of catecholamines, increased heart rate, and increased smooth muscle relaxation.  In addition, it reaches a peak level 30-60 minutes after consumption and it’s half-life occurs 2.5-4.5 hours after ingestion (Wilkinson 242).

Also, increased oestrogen in pregnancy increases the half-life of caffeine to 7 hr-10.5hr during the last weeks of pregnancy (Bech, and Olsen 58). Furthermore, caffeine has the ability to pass through the placenta to the fetus.  The fetus does not express the enzymes needed in order to inactivate caffeine molecules and the metabolites formed from the breakdown of caffeine are stored in the fetal brain (Wilkinson 242).

Studies have tried to obtain evidence linking caffeine to low birth weights; however, there are other factors associated with people who intake caffeine, such as smoking and alcohol.  One study by Bech et al. (2007), measured the effect of caffeine on birth weight.  The study used a population of Danish women who consumed at least three cups of coffee per day.  The study found that a moderate decrease in caffeine during the second half of pregnancy had no significant effect on birth weight or length of pregnancy.  Therefore, it can be suggested that caffeine does in fact have an effect on birth weight and gestation period.  Another study conducted by Forteir et al. (1993) found that caffeine can influence a low birth weight through growth retardation.  Growth retardation is diagnosed when an infant is less than 10^th percentile for both sex and gestational age.  In Forteir et al (1993), it was found that for each increase in average caffeine consumption per day, there was a correlation with an increase in growth retardation (Bech, and Olsen 58).

Overall, studies have linked caffeine with fetal development and gestation.  There are known physiological effects of caffeine and these effects are increased during pregnancy; therefore, further research should focus on controlled studies in order to further confirm the correlation and provide more educational awareness to women who consider getting pregnant.

Study Evaluation

Random pregnant women have been chosen for this study using questionnaire. To gain representative samples, the questionnaire contained the following criteria needed for this study:

• No epilepsy.
• No low birth weight cases.
• No kidney diseases.
• Preterm delivery.
• Metabolic disorders.

The pregnant women who were eligible and fit in the criteria were interviewed by telephone. However, one of the biases in this study is the lack of participant diversity. This therefore means that the study did not present women from different genetic and cultural backgrounds.  There was a large number of participants in this study which ultimately led to the withdrawal of some of the women; some stopped drinking caffeinated coffee for no specific reason and others who suffered from headaches. By estimation, the participant population of 1153 of the respondents were considered for the study. The participants were divided into two groups for two different studies; one trial dealt with the effect of caffeine on the birth weight and about 568 was chosen randomly for this. The other trial had 629 participants; it was related to the effect on the gestational length.  Each study divided the participants into baseline group and exposed group. The baseline group is the group who is not exposed to a risk factor which in this situation is the caffeine, whereas, the exposed group were exposed to caffeine (Al-Shoshan 575).  The trial was a double blind trail, which meant that neither of the coordinators nor the participants knew whether the coffee was caffeinated or not⁹.  Another bias arose here due to the fact that the protocol was not strict, the paper presented that some participants in both groups were allowed to drink other beverages that contained caffeine such as sodas. Therefore, some women in the baseline group might have drunk other beverages that raised her caffeine level during the trial and this may have led to imprecise measurements which gave less accurate results.

In general, the results were unexpectedly negative even though the paper answered the addressed question.  In other words, the results showed no significant differences in birth weight and gestational length between the two groups.  The coordinators believe that there were other factors in addition to caffeine that may influence the birth weight and gestational length. Thus, two analyses were performed, the first analyzed the data obtained from the trial and it did not show significant differences between the two groups and the latter one took other factors. For example, abdominal circumflex, smoking, alcohol etc….

The results were obtained by measuring the average and then they were compared. However, the confidence interval (CI) was used to reduce the bias. Confidence interval gives us the margin of errors or in other words, it is used to indicate a reliability of an estimate (Al-Shoshan 575).      Unintentionally, the second analysis showed a correlation between smoking and caffeine. The study showed that women who smoke 10 or more cigarettes a day gave birth to babies with low birth weight. The study reported that women who smoked in the exposed group had lower birth weight comparing to those who smoke in the baseline group. This left an unanswered question, what are the effects of smoking on the caffeine?

Discussion and Analysis

Today, Caffeinated drinks are some of the world’s most commonly consumed drinks, usually in the form of coffee, tea and soda drinks; In the United States alone 80% of the population consumes caffeine in some form.¹¹ Since caffeine is a psychoactive drug, it has stirred a lot of studies on its effects on women during pregnancy and their newborns post-partum.

Studies have shown that different people respond differently to caffeine in the way it is metabolized which may indicate that genetic predisposition is a factor (Shmidt and Romitti 60). Caffeine like many other drugs has withdrawal symptoms that include, headaches, fatigue and concentration difficulties; so it s recommended that the pregnant women do not immediately cut herself off of caffeine but instead reduce the caffeine intake slowly to below the daily recommended dose . It would be better if during the pregnancy period she drinks a lot of water to help remove the caffeine and ultimately exchange the caffeinated drink with a healthier caffeine free drink (Shmidt and Romitti 60).

Consumption of Caffeine has been associated with declined birth weight and increased probabilities of the fetus being small for its gestational age. This relation was supported by consistent outcomes from different sources of caffeine. According to the World Health Organization (WHO), even though a pregnant mother is consuming caffeine below the recommended daily dose, there is still an increased risk of the fetus being small for its gestational age. A cohort study was conducted in 2008 to determine whether caffeine increases the risk of miscarriages in pregnant women. The study showed that there was an 80% increase in the risk of miscarriage in pregnant women in the study who have consumed 200 milligrams or more per day of caffeine; from this study and many others it is recommended today that pregnant women should avoid caffeine intake or limit themselves to a maximum of 200 milligrams per day.¹⁵However, some studies suggest that the maximum consumption is 300 milligrams per day (Fortei 175).

Some other effects on infants may include neural tube defects such as Spina Bifida and Encephalocele. In 2009, a study was conducted on this matter quoted, “if the found association is causal, an estimate 21% of Spina Bifida and Encephalocele cases in the United States could be prevented by eliminating maternal caffeine intak (Al-Shoshan 575). Genetics and the environment, which includes the daily characteristics of the mother during pregnancy, determine the general health of a baby. This article studies the effect of smoking as a secondary study but more recent articles study the effect of alcohol consumption and smoking; even though the percentage of women who consume alcohol and smoking are less than that of caffeine, the effects are far more severe. The study concluded that both alcohol and smoking increased the risk of sudden infant death syndrome (Bech, and Olsen 58). Most of the previous studies focused on the association between caffeine consumption throughout pregnancy and birth weight. In addition to that, low birth weight was used as an outcome instead of “actual fetal growth”. The analysis of fetal growth characteristics has proved to be a more appropriate assessment than birth weight in analyzing the effects of caffeine intake throughout the pregnancy period.

However, investigations and studies about the association of caffeine and the effect it has on pregnancy are “contradictory”, mainly due to challenges in the design of the study. The correlation of caffeine to growth restriction remains uncertain and so a final conclusion cannot be made at this time about this specific correlation. As a further matter on this particular subject, future studies on the assessing of caffeine intake during pregnancy may prove difficult due to the many conflictions on the matter. As well as that it not clear on how much caffeine quantity or in what product it is consumed from that may cause the fetal or newborn defects if any are present (Bech, and Olsen 58).

Ethical Issues Surrounding Research

Throughout today’s society regardless of what type of research is being conducted, one of the most important aspects is whether or not the health related benefits are greater than the potential risk it may cause to the participants. The following study succeeded in determining that caffeine on its own had no direct perceived effect on birth weight or gestational length. To some this may have sounded like study without much relevance, however what most people fail to grasp, is that a low birth weight can cause severely profound effects on the child. Low birth weight has been proven on numerous accounts to be associated with fetal and prenatal mortality as well as causing inhibited growth, cognitive development and problematic chronic diseases further down the road.

Participants of the study were given an endless supply of either caffeinated or decafinated coffee to consume during the trial, and were interviewed at different stages throughout the testing process. Due to the close monitoring that occurred within the trial there was no perceptible risk to the patients. Patients were not forced to change their drinking habits, and in fact were permitted to withdraw at any moment had they felt unsafe, as per the agreement in the consent form. However,  the fact that coffee was widely available in unlimited quantities may have posed a risk to the patients, because patients may have exploited the idea of drinking unlimited coffee, especially had the coffee been deemed problematic to gestational length or birth weight. Overall this study clinically had provided us with great insight but more importantly reassurance that caffeine had no negative effects on pregnancy, this study provided minimum or no risk to the participants and tremendous benefit to the public

The Issue of Informed consent

Following the “Nuremberg Code” and later on the “Declaration of Helenski” informed consent has become one of the most essential components in proceeding with medical research.  The Danish research team took a very ethical approach to reach the participants, as the patients in no way or another were misled or swayed. The study reached out to participants on two separate occasions; on both occasions the eligible participants were contacted individually and given a detailed overview of the study along with the consent form. Consent is a vital element in research without which the respondents cannot participate in a study. Past cases such as the thalidomide drug incident in the 50s, where patients were given the drug unawaringely of its negative consequence, sadly this eventually lead to nearly 12000 birth deformities. The caffeine and pregnancy study demonstrated excellent ethical procedure in terms of informing the participants of the type of study that was to be conducted, covering all aspect of the research (Wilkinson 242).

Respect for the patient

Prior to the commencement of the study the participants were provided with ample amounts of information. Within the actual consent form itself it stressed vital information to the participants, such as having the ability to withdraw from the study at any moment had they wanted to, as well as reassurance on the privacy of their information. Participants were promised that only team members would have access to their information and results, more importantly once the figures were published they were promised to be confidential.  Lastly they were assured of their safety and the coffee was straightforward “instant coffee” without any modifications that could have be purchased from any local supermarket and that it had no negative effects on their pregnancy.

Fair selection of participants

Enrolling pregnant women in research of any sort has always been a long topic of controversy’s, mainly due to the fact that various incidents, particularly the thalidomide disaster in the 1950s13. The study was particularly specific in terms of inclusion criteria, which included pregnant women that were less than 20 weeks, and consumed at least three cups of coffee a day. The criteria is quite fair considering the entire study was based on pregnancy, there was no evident discrimination what so ever. It was either you filled the description or not the study was open to women of all backgrounds. Under no circumstances are there signs of bias in the selection. It is important to note that the participants, all being pregnant women, belong to a vulnerable group. Vulnerable groups are typically untouchable when it comes medical research, unless there are compelling reasons as to why it would it be beneficial to have them included. This is simply because research could pose a serious risk on the fetus. Given the participants are in a vulnerable group, it is important that they should be informed of any such possible risks, it is well documented that a fetus does not metabolize caffeine well. Caffeine consumption during pregnancy is associated with an increased risk of fetal growth restriction and this association continues throughout pregnancy 14. There was no external pressure directed towards the participants, they received detailed information on the study and were required to fill out a consent form that was well detailed. The participants would later complete a phone interview around 12 weeks of pregnancy with further information regarding the inclusion criteria, implying their participation is voluntary. The consent form clearly indicates that participants could withdraw from the research at their own will, thus this did not limit the participants’ autonomy while safeguarding the participants’ freedom.

Summary

The natural response of the body to caffeine intake is usually relatively connected to how the nervous system is affected by the substance. Some of the common reactions include dilation of the pupils, higher rate of blood pressure, release of insulin into the blood stream and a faster rate of metabolism. These are only a few of the said physical impacts of caffeine intake in regular individuals. However, when it comes to pregnant women, the effect is more than just individualized. The infant that is growing within the woman’s body is expected to be affected at some rate by the said intake of caffeine. As the caffeine affects the central nervous system and how it binds with the body receptors specifically create an impact on how the body functions, thus creating a distinct difference of function when it comes to assisting the development of a growing infant.

Although modern studies have shown that minimal caffeine intake does not do much to the infant’s growth, consuming more than 300 milligrams of caffeine is another matter to consider. The system is simple; anything the mother takes in, the infant takes in as well as it is fully dependent on what the mother consumes because of the connection that they have through the umbilical cord. Hence, when a mother drinks caffeinated beverages, the infant absorbs the same substance directly. Due to the fact that the babies do not have well developed parts yet, their body cannot immediately detoxify the caffeine their bodies are forced to process.

Hence, even though clinical tests do not provide strong evidences of caffeine affecting the development of the infants within a mother’s womb, it is still strongly advised that pregnant women take precaution in taking in such types of beverages. It is always better to be safe than sorry; since conclusions on the matter have not been released yet, it is strongly imposed by doctors and medical specialists that there is nothing wrong with being extra careful regarding the matter.

Conclusion

Noted through the pages of this research, it was found out that there are but low rate of confirmation on the effect of caffeine when it comes to birth weight of infants. Through carefully deciphering the notes taken from the references used in this research, this study is able to point out that the necessary intake of caffeine among particular mothers do create a distinct point of keeping the mood of the mothers at level. It is then suggested that even though mothers are not being judged for their choice of beverage, they are advised to lessen intake of highly caffeinated drinks due to the fact that it does have an effect on the development of the body function of their unborn child. Although medical procedures do not confirm fully the occurrence of such connection between caffeine intake and the emergence of low birth weight among newborn babies, it is still safer for mothers to take precaution and be aware on how their bodies work to feed their unborn child. From the point of knowing such system, they are likely expected to take note of the responsibility they have on assuring the health’s integrity of their baby even while it is still inside their bodies.

Mothers are considered to be the very source of food and nourishment of every unborn child. Knowing the fact that whatever they eat or drink is directly absorbed by their babies should impose a sense of precaution among them as they choose what to take in while they are pregnant. It does not hurt to put on a little sacrifice for the span of nine months if it would mean having healthier babies in the end.

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